Схемы самодельных сварочных инверторов: Сварочный инвертор своими руками

Как сделать инверторный сварочный аппарат своими руками: схемы

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Инверторная сварка своими руками — это очень просто

Инверторная сварка — это современное устройство, которое пользуется широкой популярностью благодаря небольшому весу аппарата и его габаритов. Инверторный механизм основывается на применении полевых транзисторов и силовых переключателей. Чтобы стать обладателем сварочного аппарата, можно посетить любой магазин инструментов и обзавестись такой полезной вещью. Но есть способ намного экономнее, который обусловлен созданием инверторной сварки своими руками. Именно второму способу и уделим внимание в данном материале и рассмотрим, как сделать сварку в домашних условиях, что для этого понадобится и как выглядят схемы.

Особенности функционирования инвертора

Сварочный аппарат инверторного типа — это не что иное, как блок питания, тот, который сейчас применяется в современных компьютерах. На чем же основывается работа инвертора? В инверторе наблюдается следующая картина преобразования электрической энергии:

1) Напряжение, потребляемое из сети, преобразуется в постоянное.

2) Ток с постоянной синусоидой преобразовывается в переменный с высокой частотой.

3) Происходит снижение значения напряжения.

4) Происходит выпрямление тока с сохранением необходимой частоты.

Перечень таковых преобразований электрической цепи необходим для того, чтобы иметь возможность снизить массу аппарата и его габаритные размеры. Ведь, как известно, старые сварочные аппараты, принцип которых основывается на снижении величины напряжения и увеличения силы тока на вторичной обмотке трансформатора. В результате благодаря высокому значению силы тока наблюдается возможность дугового сваривания металлов. Для того чтобы сила тока увеличивалась, а напряжение снижалось, на вторичной обмотке уменьшается число витков, но при этом увеличивается сечение проводника. В результате можно заметить, что сварочный аппарат трансформаторного типа не только имеет значительные габариты, но и приличный вес.

Для решения проблемы был предложен вариант реализации сварочного аппарата посредством инверторной схемы. Принцип инвертора основывается на увеличении частоты тока до 60 или даже 80 кГц, тем самым осуществляя снижение массы и габаритов самого устройства. Все что потребовалось для реализации инверторного сварочного аппарата — это увеличить частоту в тысячи раз, что стало возможным благодаря применению полевых транзисторов.

Транзисторы обеспечивают сообщение между собой с частотой около 60-80 кГц. На схему питания транзисторов приходит постоянное значение тока, что обеспечивается благодаря применению выпрямителя. В качестве выпрямителя используется диодный мост, а выравнивание значения напряжения обеспечивают конденсаторы.

Переменный ток, который передается после прохождения через транзисторы на понижающий трансформатор. Но при этом в качестве трансформатора используется в сотни раз уменьшенная катушка. Почему используется катушка, потому как частота тока, которая подается на трансформатор, уже увеличена в 1000 раз благодаря полевым транзисторам. В результате получаем аналогичные данные, как и при работе трансформаторной сварки, только с большой разницей в весе и габаритах.

Что нужно для сборки инвертора

Чтобы собрать самостоятельно инверторную сварку, нужно знать, что схема рассчитывается, прежде всего, на потребляющее напряжение величиной 220 Вольт и током на 32 Ампера. Уже после преобразования энергии на выходе ток будет увеличен почти в 8 раз и будет достигать 250 Ампер. Такого тока достаточно для того, чтобы создать прочный шов электродом на расстоянии до 1 см. Для реализации блока питания инверторного типа потребуется воспользоваться следующими составляющими:

1) Трансформатор, состоящий из ферритного сердечника.

2) Обмотка первичного трансформатора со 100 витками провода диаметром 0,3 мм.

3) Три вторичных обмотки:

— внутренняя: 15 витков и диаметром провода 1 мм;

— средняя: 15 витков и диаметром 0,2 мм;

— наружная: 20 оборотов и диаметром 0,35 мм.

Кроме того, чтобы собрать трансформатор, потребуются следующие элементы:

— медные провода;

— стеклоткань;

— текстолит;

— электротехническая сталь;

— хлопчатобумажный материал.

Как выглядит схема инверторной сварки

Для того, чтобы понимать, что вообще собой представляет сварочный инверторный аппарат, необходимо рассмотреть схему, представленную ниже.

Электрическая схема инверторной сварки

Все эти компоненты необходимо объединить и тем самым получить сварочный аппарат, который будет незаменимым помощником при выполнении слесарных работ. Ниже представлена принципиальная схема инверторной сварки.

Схема блока питания инверторной сварки

Плата, на которой находится блок питания аппарата, монтируется отдельно от силовой части. Разделителем между силовой частью и блоком питания выступает металлический лист, подсоединенный к корпусу агрегата электрически.

Для управления затворками применяются проводники, припаивать которые нужно поблизости транзисторов. Эти проводники соединяются между собой парно, а сечение этих проводников не играет особой роли. Единственное, что важно учитывать — это длина проводников, которая не должна превышать 15 см.

Для человека, который не знаком с основами электроники, прочесть такого рода схему проблематично, не говоря уже о назначении каждого элемента. Поэтому если у вас нет навыков работы с электроникой, то лучше попросить знакомого мастера помочь разобраться. Вот, к примеру, ниже изображена схема силовой части инверторного сварочного аппарата.

Схема силовой части инверторной сварки

Как собрать инверторную сварку: поэтапное описание + (Видео)

Для сборки инверторного сварочного аппарата необходимо выполнить следующие этапы работы:

1) Корпус. В качестве корпуса для сварки рекомендуется воспользоваться старым системником от компьютера. Он подходит лучше всего, так как в нем имеется необходимое количество отверстий для вентиляции. Можно использовать старую 10-литровую канистру, в которой можно вырезать отверстия и разместить кулера. Для увеличения прочности конструкции из корпуса системника необходимо разместить металлические уголки, которые закрепляются с помощью болтовых соединений.

2) Сборка блока питания. Важным элементом блока питания является именно трансформатор. В качестве основы трансформатора рекомендуется воспользоваться ферритом 7х7 или 8х8. Для первичной обмотки трансформатора необходимо осуществить намотку проволоки по всей ширине сердечника. Такая немаловажная особенность влечет за собой улучшение работы устройства при появлении перепадов напряжения. В качестве проволоки обязательно нужно использовать медные провода марки ПЭВ-2, а в случае отсутствия шины, провода соединяются в один пучок. Стеклоткань используется для изоляции первичной обмотки. Сверху после слоя стеклоткани необходимо намотать витки экранирующих проводов.

Трансформатор с первичной и вторичной обмотками для создания инверторной сварки

3) Силовая часть. В качестве силового блока выступает понижающий трансформатор. В качестве сердечника для понижающего трансформатора применяются два вида сердечников: Ш20х208 2000 нм. Между обоими элементами важно обеспечить зазор, что решается путем расположения газетной бумаги. Для вторичной обмотки трансформатора характерно наматывание витков в несколько слоев. На вторичную обмотку трансформатора необходимо укладывать три слоя проводов, а между ними устанавливаются прокладки из фторопласта. Между обмотками важно расположить усиленный изоляционный слой, который позволит избежать пробоя напряжения на вторичную обмотку. Необходимо установить конденсатор напряжением не менее 1000 Вольт.

Трансформаторы для вторичной обмотки от старых телевизоров

Чтобы обеспечить циркуляцию воздуха между обмотками, необходимо оставить воздушный зазор. На ферритовом сердечнике собирается трансформатор тока, который включается в цепь к плюсовой линии. Сердечник необходимо обмотать термобумагой, поэтому в качестве этой бумаги лучше всего использовать кассовую ленту. Выпрямительные диоды крепятся к алюминиевой пластине радиатора. Выходы этих диодов следует соединить неизолированными проводами, сечение которых составляет 4 мм.

3) Инверторный блок. Главным предназначением инверторной системы — это преобразование постоянного тока в переменный с высокой частотой. Для обеспечения повышения частоты и применяют специальные полевые транзисторы. Ведь именно транзисторы работают на открытие и закрытие с высокой частотой.

Рекомендуется использовать не один мощный транзистор, а лучше всего реализовывать схему на основании 2 менее мощных. Это нужно для того, чтобы иметь возможность стабилизации частоты тока. В схеме не обойтись и без конденсаторов, которые соединяются последовательно и дают возможность решить такие проблемы:

Инвертор на алюминиевой пластине

4) Система охлаждения. На стенке корпуса следует установить вентиляторы охлаждения, а для этого можно использовать компьютерные кулера. Необходимы они для того, чтобы обеспечить охлаждение рабочих элементов. Чем больше вентиляторов будет использовано, тем лучше. В частности, обязательно требуется установить два вентилятора для обдува вторичного трансформатора. Один кулер будкт обдувать радиатор, тем самым не допуская перегрева рабочих элементов — выпрямительных диодов. Диоды монтируются на радиаторе следующим образом, как показано на фото ниже.

Выпрямительный мост на радиаторе охлаждения

Рекомендуется воспользоваться таким вспомогательным элементом, как термодатчик.

Фото терморегулятора

Его рекомендуется устанавливать на самом нагревающемся элементе. Этот датчик будет срабатывать при достижении критической температуры нагрева рабочего элемента. При его срабатывании будет отключаться питание инверторного устройства.

Мощный вентилятор для охлаждения инверторного устройства

При работе инверторная сварка очень быстро нагревается, поэтому наличие двух мощных кулеров является обязательным условием. Эти кулеры или вентиляторы располагаются на корпусе устройства, чтобы они работали на вытяжку воздуха.

Поступать свежий воздух в систему будет благодаря отверстиям в корпусе устройства. В системном блоке эти отверстия уже имеются, а если вы используете любой другой материал, то не забудьте обеспечить приток свежего воздуха.

5) Пайка платы является ключевым фактором, так как именно на плате основывается вся схема. На плате диоды и транзисторы важно устанавливать на встречном направлении друг к другу. Плата монтируется непосредственно между радиаторами охлаждения, с помощью чего соединяется вся цепь электроприборов. Питающая цепь рассчитывается на напряжение 300 В. Дополнительное расположение конденсаторов емкостью 0,15 мкФ дает возможность сброса избыточной мощности обратно в цепь. На выходе трансформатора располагаются конденсаторы и снабберы, с помощью которых осуществляется гашение перенапряжений на выходе вторичной обмотки.

6) Настройка и отладка работы. После того, как инверторная сварка будет собрана, потребуется провести еще несколько процедур, в частности, настроить функционирование агрегата. Для этого следует подключить к ШИМ (широтно-импульсный модулятор) напряжение в 15 Вольт и запитать кулер. Дополнительно включается в цепь реле через резистор R11. Реле включается в цепь для того, чтобы избежать скачков напряжения в сети 220 В. Обязательно важно провести контроль за включением реле, после чего подать питание на ШИМ. В результате должна наблюдаться картина, при которой должны исчезнуть прямоугольные участки на диаграмме ШИМ.

Устройство самодельного инвертора с описанием элементов

Судить о правильности соединения схемы можно в том случае, если во время настройки реле выдает 150 мА. В случае, когда же наблюдается слабый сигнал, то это говорит о неправильности соединения платы. Возможно, имеется пробой одной из обмоток, поэтому для устранения помех потребуется укоротить все питающие электропровода.

Инверторная сварка в корпусе системного блока от компьютера

 

Проверка работоспособности устройства

После проведения всех сборочных и отладочных работ остается только провести проверку работоспособности получившегося сварочного аппарата. Для этого запитывается прибор от электросети 220 В, затем задается высокие показатели силы тока и по осциллографу осуществляется сверка показаний. В нижней петле напряжение должно быть в переделах 500 В, но не более 550 В. Если все выполнено правильно со строгим подбором электроники, тогда показатель напряжения не превысит значения в 350 В.

Итак, теперь можно проверить сварку в действии, для чего используем необходимые электроды и осуществляем раскраивание шва до полного выгорания электрода. После этого важно проконтроллировать температуру трансформатора. Если трансформатор попросту закипает, тогда схема имеет свои недочеты и лучше далее не продолжать рабочий процесс.

После раскраивания 2-3 швов радиаторы нагреются до высокой температуры, поэтому после этого важно дать возможность им остыть. Для этого достаточно 2-3 минутной паузы, в результате чего температура понизится до оптимального значения.

Проверка сварочного аппарата

Как пользоваться самодельным аппаратом

После включения в цепь самодельного аппарата, контроллер в автоматическом режиме задаст определенную силу тока. При напряжении провода менее 100 Вольт, то это говорит о неисправности устройства. Придется разобрать аппарат и снова повторно провести проверку правильности сборки.

С помощью такого вида сварочных аппаратов можно осуществлять спайку не только черных, но и цветных металлов. Для того чтобы собрать сварочный аппарат, потребуется не только владение основами электротехники, но и свободное время для реализации задумки.

Инверторная сварка — незаменимая вещь в гараже у любого хозяина, поэтому если вы еще не обзавелись таким инструментом, то вы можете сделать его самостоятельно.

 

90000 7 Simple Inverter Circuits you can Build at Home 90001 90002 These 7 inverter circuits may look simple with their designs, but are able to produce a reasonably high power output and an efficiency of around 75%. Learn how to build this cheap mini inverter and power small 220V or 120V appliances such drill machines, LED lamps, CFL lamps, hair dryer, mobile chargers, etc through a 12V 7 Ah battery. 90003 90004 What is a Simple Inverter 90005 90002 An inverter which uses minimum number of components for converting a 12 V DC to 230 V AC is called a simple inverter.A 12 V lead acid battery is the most standard form of battery which is used for operating such inverters. 90003 90002 Let’s begin with the most simplest in the list which utilizes a couple of 2N3055 transistors and some resistors. 90003 90004 1) Simple Inverter Circuit using Cross Coupled Transistors 90005 90002 The article deals with the construction details of a mini inverter. Read to know regrading the construction procedure of a basic inverter which can provide reasonably good power output and yet is very affordable and sleek.90003 90002 There may be a huge number of inverter circuits available over the internet and electronic magazines. But these circuits are often very complicated and hi-end type of inverters. 90003 90002 Thus we are left with no choice but just to wonder how to build power inverters that can be not only easy to build but also low cost and highly efficient in its working. 90003 90018 12v to 230v inverter circuit diagram 90019 90002 Well your search for such a circuit ends here. The circuit of an inverter described here is perhaps the smallest as far its component count goes yet is powerful enough to fulfill most of your requirements.90003 90004 Construction Procedure 90005 90002 To begin with, first make sure to have proper heatsinks for the two 2N3055 transistors. It can be fabricated in the following manner: 90003 90026 90027 Cut two sheets of aluminum of 6/4 inches each. 90028 90029 90026 90027 Bend one end of the sheet as shown in the diagram. Drill appropriate sized holes on to the bends so that it can be clamped firmly to the metal cabinet. 90028 90027 If you find it difficult to make this heatsink you can simply purchase from your local electronic shop shown below: 90028 90029 90026 90027 Also drill holes for fitting of the power transistors.The holes are 3mm in diameter, TO-3 type of package size. 90028 90027 Fix the transistors tightly on to the heatsinks with the help of nuts and bolts. 90028 90027 Connect the resistors in a cross-coupled manner directly to the leads of the transistors as per the circuit diagram. 90028 90027 Now join the heatsink, transistor, resistor assembly to the secondary winding of the transformer. 90028 90027 Fix the whole circuit assembly along with the transformer inside a sturdy, well ventilated metal enclosure.90028 90027 Fit the output and input sockets, fuse holder etc. externally to the cabinet and connect them appropriately to the circuit assembly. 90028 90029 90002 Once the above heatsink installation is over, you simply need to interconnect a few high watt resistors and the 2N3055 (on heatsink) with the selected transformer as given in the following diagram. 90003 90018 Complete Wiring Layout 90019 90002 After the above wiring is completed, it’s time to hook it up with a 12V 7Ah battery, with a 60 watt lamp attached at the transformer secondary.When switched ON the result would be an instant illumination of the load with an astonishing brightness. 90003 90002 Here the key element is the transformer, make sure the transformer is genuinely rated at 5 amp, otherwise you may find the output power a lot lesser than the expectation. 90003 90002 I can tell this from my experience, I built this unit twice, once when I was in college, and the second time recently in the year 2015. Although I was more experienced during the recent venture I could not get the awesome power that I had acquired from my previous unit.The reason was simple, the previous transformer was a robust custom built 9-0-9V 5 amp transformer, compared to the new one in which I had used probably a falsely rated 5 amp, which was actually only 3 amp with its output. 90003 90018 Parts List 90019 90002 You will require just the following few components for the construction: 90003 90026 90027 R1, R2 = 100 OHMS./ 10 WATTS WIRE WOUND 90028 90027 R3, R4 = 15 OHMS / 10 WATTS WIRE WOUND 90028 90027 T1, T2 = 2N3055 POWER TRANSISTORS (MOTOROLA).90028 90027 TRANSFORMER = 90072 9- 0- 9 VOLTS 90073/8 AMPS or 5 amps. 90028 90027 AUTOMOBILE BATTERY = 12 VOLTS / 10Ah 90028 90027 ALUMINUM HEATSINK = CUT AS PER THE REQUIRED SIZE. 90028 90027 VENTILATED METAL CABINET = AS PER THE SIZE OF THE WHOLE ASSEMBLY 90028 90029 90018 Video Test Proof 90019 90002 90085 90086 90003 90018 How to Test it? 90019 90026 90027 The testing of this mini inverter is done in the following method: 90028 90027 For testing purpose connect a 60 watt incandescent bulb to the output socket of the inverter.90028 90027 Next, connect a fully charged 12 V automobile battery to its supply terminals. 90028 90027 The 60 watt bulb should immediately light up brightly, indicating that the inverter is functioning properly. 90028 90027 This concludes the construction and the testing of the inverter circuit. 90028 90027 I hope from the above discussions you must have clearly understood how to build an inverter which is not only simple to construct but also very affordable to each of you. 90028 90027 It can be used to power small electrical appliances like soldering iron, CFL lights, small portable fans etc.The output power will lie in the vicinity of 70 watts and is load dependent. 90028 90027 The efficiency of this inverter is around 75%. The unit may be connected to your vehicles battery itself when outdoors so that the trouble of carrying an extra battery is eliminated. 90028 90029 90018 Circuit Operation 90019 90002 The functioning of this mini inverter circuit is rather unique and different from the normal inverters which involve discrete oscillator stage for powering the transistors. 90003 90002 However here the two sections or the two arms of the circuit operate in a regenerative manner.Its very simple and may be understood through the following points: 90003 90002 The two halves of the circuit no matter how much they are matched will always consist a slight imbalance in the parameters surrounding them, like the resistors, Hfe, transformer winding turns etc. 90003 90002 Due to this, both the halves are not able to conduct together at one instant. 90003 90002 Assume that the upper half transistors conduct first, obviously they will be getting their biasing voltage through the lower half winding of the transformer via R2.90003 90002 However the moment they saturate and conduct fully, the entire battery voltage is pulled through their collectors to the ground. 90003 90002 This sucks-out dry any voltage through R2 to their base and they immediately stop conducting. 90003 90002 This gives an opportunity for the lower transistors to conduct and the cycle repeats. 90003 90002 The whole circuit thus starts to oscillate. 90003 90002 The base Emitter resistors are used to fix a particular threshold for their conduction to break, they help to fix a base biasing reference level.90003 90002 The above circuit was inspired from the following design by Motorola: 90003 90132 90002 90072 UPDATE: You may also want to try this: 50 watt Mini Inverter Circuit 90073 90003 90132 90002 Output Waveform better than square wave (Reasonably suitable for all electronic appliances )) 90003 90140 90141 PCB Design for the above explained simple 2N3055 Inverter Circuit (Track Side Layout) 90142 90004 2) Using IC 4047 90005 90002 As shown above a simple yet useful little inverter can be built using just a single IC 4047.The IC 4047 is a versatile single IC oscillator, which will produce precise ON / OFF periods across its output pin # 10 and pin # 11. The frequency here could be determined by accurately calculating the resistor R1 and capacitor C1. These components determine the oscillation frequency at the output of the IC which in turn sets the output 220V AC frequency of this inverter circuit. It may set at 50Hz or 60Hz as per individual preference. 90003 90002 The battery, mosfet and the transformer can be modified or upgraded as per the required output power specification of the inverter.90003 90002 For calculating the RC values, and the output frequency please refer to the datasheet of the IC 90003 90141 90072 Video Test Results 90073 90142 90002 90156 90086 90003 90018 3) Using IC 4049 90019 IC 4049 pin details 90002 In this simple inverter circuit we use a single IC 4049 which includes 6 NOT gates or 6 inverters inside. In the diagram above N1 —- N6 signify the 6 gates which are configured as oscillator and buffer stages. The NOT gates N1 and N2 are basically used for the oscillator stage, the C and R can be selected and fixed for determining the 50Hz or 60 Hz frequency as per country specs 90003 90002 The remaining gates N3 to N6 are adjusted and configured as buffers and inverters so that the ultimate output results in producing alternating switching pulses for the power transistors.The configuration also ensures that no gates are left unused and idle, which may otherwise require their inputs to be terminated separately across a supply line. 90003 90002 The transformer and battery may be selected as per the power requirement or the load wattage specifications. 90003 90002 The output will be purely a square wave output. 90003 90002 90072 Formula for calculating frequency is given as: 90073 90003 90002 90072 f = 1 /1.2RC, 90073 90003 90002 where R will be in Ohms and F in Farads 90003 90004 4) Using IC 4093 90005 IC 4093 pin details 90002 Quite similar to the previous NOT gate inveter, the NAND gate based simple inverter shown above can be built using a single 4093 IC.The gates N1 to N4 signify the 4 gates inside the IC 4093. 90003 90002 N1, is wired as an oscillator circuit, for generating the required 50 or 60Hz pulses. These are appropriately inverted and buffered using the remaining gates N2, N3, N4 in order to finally deliver the alternately switching frequency across the bases of the power BJTs, which in turn switch the power transformer at the supplied rate for generating the required 220V or 120V AC at the output. 90003 90002 Although any NAND gate IC would work here, using the IC 4093 is recommended since it features Schmidt trigger facility, which ensures a slight lag in switching and helps creating a kind of dead-time across the switching outputs, making sure that the power devices are never switched ON together even for a fraction of a second.90003 90004 5) Another Simple NAND gate Inverter using MOSFETs 90005 90002 Another simple yet powerful inverter circuit design is explained in the following paragraphs which can be built by any electronic enthusiast and used for powering most of the household electrical appliances (resistive and SMPS loads) . 90003 90002 The use of a couple of mosfets influences a powerful response from the circuit involving very few components, however the square wave configuration does limit the unit from quite a few useful applications.90003 90018 Introduction 90019 90002 Calculating MOSFET parameters may seem to involve a few difficult steps, however by following the standard design enforcing these wonderful devices into action is definitely easy. 90003 90002 When we talk about inverter circuits involving power outputs, MOSFETs imperatively become a part of the design and also the main component of the configuration, especially at the driving output ends of the circuit. 90003 90002 Inverter circuits being the favorites with these devices, we would be discussing one such design incorporating MOSFETs for powering the output stage of the circuit.90003 90002 Referring to the diagram, we see a very basic inverter design involving a square wave oscillator stage, a buffer stage and the power output stage. 90003 90002 The use of a single IC for generating the required square waves and for buffering the pulses particularly makes the design easy to make, especially for the new electronic enthusiast. 90003 90018 Using IC 4093 NAND Gates for the Oscillator Circuit 90019 90002 The IC 4093 is a quad NAND gate Schmidt Trigger IC, a single NAND is wired up as an astable multivibrator for generating the base square pulses.The value of the resistor or the capacitor may be adjusted for acquiring either a 50 Hz or 60 Hz pulses. For 220 V applications 50 Hz option needs to be selected and a 60 Hz for the 120 V versions. 90003 90002 The output from the above oscillator stage is tied with a couple of more NAND gates used as buffers, whose outputs are ultimately terminated with the gate of the respective MOSFETs. 90003 90002 The two NAND gates are connected in series such that the two mosfets receive opposite logic levels alternately from the oscillator stage and switch the MOSFETs alternately for making the desired inductions in the input winding of the transformer.90003 90018 Mosfet Switching 90019 90002 The above switching of the MOSFETs stuffs the entire battery current inside the relevant windings of the transformer, inducing an instant stepping up of the power at the opposite winding of the transformer where the output to the load is ultimately derived. 90003 90002 The MOSFETs are capable of handling more than 25 Amps of current and the range is pretty huge and therefore becomes suitable driving transformers of different power specs. 90003 90002 It’s just a matter of modifying the transformer and the battery for making inverters of different ranges with different power outputs.90003 90141 Parts List for the above explained 150 watt inverter circuit diagram: 90142 90026 90027 R1 = 220K pot, needs to be set for acquiring the desired frequency output. 90028 90027 R2, R3, R4, R5 = 1K, 90028 90027 T1, T2 = IRF540 90028 90027 N1-N4 = IC 4093 90028 90027 C1 = 0.01uF, 90028 90027 C3 = 0.1uF 90028 90029 90002 TR1 = 0-12V input winding , current = 15 Amp, output voltage as per the required specs 90003 90002 90072 Formula for calculating frequency will be identical to the one described above for IC 4049.90073 90003 90002 f = 1 /1.2RC. where R = R1 set value, and C = C1 90003 90004 6) Using IC 4060 90005 90002 If you have a single 4060 IC in your electronic junk box, along with a transformer and a few power transistors, you are probably all set to create your simple power inverter circuit using these components. The basic design of the proposed IC 4060 based inverter circuit can be visualized in the above diagram. The concept is basically the same, we use the IC 4060 as an oscillator, and set its output to create alternately switching ON OFF pulses through an inverter BC547 transistors stage.90003 90002 Just like IC 4047, the IC 4060 requires an external RC components for setting up its output frequency, however, the output from the IC 4060 are terminated into 10 individual pinouts in a specific order wherein the output generate frequency at a rate twice that of its preceding pinout. 90003 90002 Although you may find 10 separate outputs with a rate of 2X frequency rate across the IC output pinouts, we have selected the pin # 7 since it delivers the fastest frequency rate among the rest and therefore may fulfil this using standard components for the RC network, which may be easily available to you no matter in which part of the globe you are situated in.90003 90002 90072 For calculating the RC values ​​for R2 + P1 and C1 and the frequency you can use the formula as described below: 90073 90003 90002 Or another way is through the following formula: 90003 90002 90072 f (osc) = 1 / 2.3 x Rt x Ct 90073 90003 90002 Rt is in Ohms, Ct in Farads 90003 90002 More info can be obtained from this article 90003 90002 Here’s yet another cool DIY inverter idea which is extremely reliable and uses ordinary parts for accomplishing a high power inverter design, and can be upgraded to any desired power level.90003 90002 Let’s learn more about this simple design 90003 90004 7) Simplest 100 Watt Inverter for the Newcomers 90005 90002 The circuit of a simple 100 watt inverter discussed in this article can be considered as the most efficient, reliable, easy to build and powerful inverter design. It will convert any 12V to 220V effectively using minimum components 90003 90018 Introduction 90019 90002 The idea was published many years back in one of the elecktor electronics magazines, I present it here so that you all can make and use this circuit for your personal applications.Let’s learn more. 90003 90002 The proposed simple 100 watt inverter circuit disign was published quite a long time ago in one of the elektor electronics magazines and according to me this circuit is one of the best inverter designs you can get. 90003 90002 I consider it to be the best because the design is well balanced, well calculated, utilizes ordinary parts and if done everything correctly would start working instantly. 90003 90002 The efficiency of this design is in the vicinity of 85% that’s good considering the simple format and low costs involved.90003 90018 Using an Transistor Astable as the 50Hz Oscillator 90019 90002 Basically the whole design is built around an astable multivibrator stage, consisting of two low power general purpose transistors BC547 along with the associated parts consisting of two electrolytic capacitors and some resistors. 90003 90002 This stage is responsible for generating the basic 50 Hz pulses required for initiating the inverter operations. 90003 90002 The above signals are at low current levels and therefore requires to be lifted to some higher orders.This is done by the driver transistors BD680, which are Darlington by nature. 90003 90002 These transistors receive the low power 50 Hz signals from the BC547 transistor stages and lift them at higher current levels so that it can be fed to the output transistors. 90003 90002 The output transistors are a pair of 2N3055 which receive an amplified current drive at their bases from the above driver stage. 90003 90018 2N3055 Transistors as the Power Stage 90019 90002 The 2N3055 transistors thus are also driven at high saturation and high current levels which gets pumped into the relevant transformer windings alternately, and converted into the required 220V AC volts at the secondary of the transformer.90003 90141 Parts List for the above explained simple 100 watt inverter circuit 90142 90026 90027 R1, R2 = 27K, 1/4 watt 5% 90028 90027 R3, R4, R5, R6 = 330 OHMS, 1/4 watt 5% 90028 90027 R7 , R8 = 22 OHMS, 5 WATT WIRE WOUND TYPE 90028 90027 C1, C2 = 470nF 90028 90027 T1, T2 = BC547, 90028 90027 T3, T4 = BD680, OR TIP127 90028 90027 T5, T6 = 2N3055, 90028 90027 D1, D2 = 1N5402 90028 90027 TRANSFORMER = 9-0-9V, 5 AMP 90028 90027 BATTERY = 12V, 26AH, 90028 90029 90018 Heatsink for the T3 / T4, and T5 / T6 90019 90002 90072 Specifications: 90073 90003 90331 90027 Power Output: 100 watts if single 2n3055 transistors are used on each channels.90028 90027 Frequency: 50 Hz, Square Wave, 90028 90027 Input Voltage: 12V @ 5 Amps for 100 Watts, 90028 90027 Output Volts: 220V or 120V (with some adjustments) 90028 90340 90002 From the above discussion you might be feeling thoroughly enlightened regarding how to build these 7 simple inverter circuits, by configuring a given basic oscillator circuit with a BJT stage and a transformer, and by incorporating very ordinary parts which may be already existing with you or accessible by salvaging an old assembled PC board.90003 90141 How to Calculate the Resistors and Capacitors for 50 Hz or 60 Hz Frequencies 90142 90002 In this transistor based inverter circuit, the oscillator design is built using a transistorized astable circuit. 90003 90002 Basically the resistors and capacitors associated with the bases of the transistors determine the frequency of the output. Although these are correctly calculated to produce approximately 50 Hz frequency, if you are further interested to tweak the output frequency as per own preference you can easily do so by calculating them through this 90072 Transistor Astable Multivibrator Calculator.90073 90003 90018 Universal Push-Pull Module 90019 90002 If you are interested to achieve a more compact an efficient design using a simple a 2 wire transformer push pull configuration, then you can try the following couple of concepts 90003 90002 The first one below uses the IC 4047, along with a couple of p channel and n channel MOSFETs: 90003 90002 If you wish to employ some other oscillator stage as per your preference, in that case you can apply the following universal design. 90003 90002 This will allow you to integrate any desired oscillator stage and get the required 220 V push pull output.90003 90002 Moreover it also has an integrated auto-changeover battery charger stage. 90003 90018 Advantages of Simple Push-Pull Inverter 90019 90002 The main advantages of this universal push-pull inverter design are: 90003 90026 90027 It uses a 2 wire transformer, which makes the design highly efficient, in terms of size and power output. 90028 90027 It incorporates a changeover with battery charger, which charges the battery when the mains is present, and during a mains failure changes over to inverter mode using the same battery to produce the intended 220 V from the battery.90028 90027 It uses ordinary p-channel and N-channel MOSFETs without any complex circuitry. 90028 90027 It is cheaper to build and more efficient than the center tap counterpart. 90028 90029 90072 UNIVERSAL PUSH PULL MOSFET MODULE WHICH WILL INTERFACE WITH ANY DESIRED OSCILLATOR CIRCUIT 90073 90018 For the Advanced Users 90019 90002 The above explained were a few straightforward inverter circuit designs, however if you think these are pretty ordinary for you, you can always explore more advanced designs which are included in this website.Here are a few more links for your reference: 90003 90132 90002 90072 More Inverter Projects for You with Full online Help! 90073 90003 90132 90141 About Swagatam 90142 90002 I am an electronic engineer (dipIETE), hobbyist, inventor, schematic / PCB designer, manufacturer. I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials. 90392 If you have any circuit related query, you may interact through comments, I’ll be most happy to help! 90003.90000 5kva Ferrite Core Inverter Circuit – Full Working Diagram with Calculation Details 90001 90002 In this post we discuss the construction of a 5000 watt inverter circuit which incorporates a ferrite core transformer and therefore is hugely compact than the conventional iron core counterparts. 90003 90004 Block Diagram 90005 90002 90007 Please note you can convert this ferrite core inverter to any desired wattage, right from 100 watt to 5 kva or as per your own preference. 90008 90003 90002 Understanding the above block diagram is quite simple: 90003 90002 The input DC which could be through a 12V, 24V or 48V battery or solar panel is applied to a ferrite based inverter, which converts it into a high frequency 220V AC output, at around 50 kHz.90003 90002 But since 50 kHz frequency may not be suitable for our home appliances, we need to convert this high frequency AC into the required 50 Hz / 220V, or 120V AC / 60Hz. 90003 90002 This is implemented through an H-bridge inverter stage, which converts this high frequency into output into the desired 220V AC. 90003 90002 However, for this the H-bridge stage would need a peak value of the 220V RMS, which is around 310V DC. 90003 90002 This is achieved using a bridge rectifier stage, which converts the high frequency 220V into 310 V DC.90003 90002 Finally, this 310 V DC bus voltage is converted back into 220 V 50 Hz using the H-bridge. 90003 90002 We can also see a 50 Hz oscillator stage powered by the same DC source. This oscillator is actually optional and may be required for H-bridge circuits which do not have its own oscillator. For example if we use a transistor based H-bridge then we may need this oscillator stage to operate the High and low side mosfets accordingly. 90003 90004 A Simple Ferrite Cote Inverter Design 90005 90002 Before we learn the 5kva version here’s a simpler circuit design for the newcomers.This circuit does not employ any specialized driver IC, rather works with only n-channel MOSFETS, and a bootstrapping stage. 90003 90002 The complete circuit diagram can be witnessed below: 90003 90032 90007 400V, 10 amp MOSFET IRF740 Specifications 90008 90035 90002 In the above simple 12V to 220V AC ferrite inverter circuit we can see a ready made 12V to 310V DC converter module being used. This means you do not have to make a complex ferrite core based transformer. For the new users this design may be very beneficial as they can quickly build this inverter without depending on any complex calculations, and ferrite core selections.90003 90038 5 kva Design Prerequisites 90039 90002 First you need to find 60V DC power supply for powering the proposed 5kVA inverter circuit. The intention is to design a switching inverter which will convert the DC voltage of 60V to a higher 310V at a lowered current. 90003 90002 The topology followed in this scenario is the push-pull topology which uses transformer on the ratio of 5:18. For voltage regulation which you may need, and the current limit – they are all powered by an input voltage source.Also at the same rate, the inverter expedites the current allowed. 90003 90002 When it comes to an input source of 20A it is possible to get 2 – 5A. However, the peak output voltage of this 5kva inverter is around 310V. 90003 90004 Ferrite Transformer and Mosfet Specifications 90005 90002 In regard to the architecture, Tr1 transformer has 5 + 5 primary turns and 18 for secondary. For switching, it is possible to use 4 + 4 MOSFET (IXFH50N20 type (50A, 200V, 45mR, Cg = 4400pF). You are also free to use MOSFET of any voltage with Uds 200V (150V) along with least conductive resistance.The gate resistance used and its efficiency in speed and capacity must be excellent. 90003 90002 The Tr1 ferrite section is constructed around 15×15 mm ferrite c. The L1 inductor is designed using five iron powder rings that may be wound as wires. For inductor core and other associated parts, you can always get it from old inverters (56v / 5V) and within their snubber stages. 90003 90004 Using a Full Bridge IC 90005 90002 For integrated circuit the IC IR2153 can be deployed. The outputs of the ICs could be seen buffered with BJT stages.Moreover, due to the large gate capacitance involved it is important to use the buffers in the form of power amplifier complementary pairs, a couple of of BD139 and BD140 NPN / PNP transistors do the job well. 90003 90004 Alternate IC can be SG3525 90005 90002 You may also try to use other control circuits like SG3525. Also, you can alter the voltage of the input and work in direct connection with the mains for testing purpose. 90003 90002 The topology used in this circuit has the facility of galvanic isolation and operating frequency is around 40 kHz.In case if you have planned to use the inverter for a small operation, you do not cooling, but for longer operation be sure to add a cooling agent using fans or large heatsinks. Most of the power is lost at the output diodes and the Schottky voltage goes low around 0.5V. 90003 90002 The input 60V could be acquired by putting 5 nos of 12V batteries in series, the Ah rating of each battery must be rated at 100 Ah. 90003 90002 90007 DATASHEET IR2153 90008 90003 90007 Please do not use BD139 / BD140, instead use BC547 / BC557, for the driver stage above.90008 90004 High Frequency 330V Stage 90005 90002 The 220V obtained at the output of TR1 in the above 5 kva inverter circuit still can not be used for operating normal appliances since the AC content would be oscillating at the input 40 kHz frequency.For converting the above 40 kHz 220V AC into 220V 50 Hz or a 120V 60Hz AC, further stages would be required as stated below: 90003 90002 First the 220V 40kHz will need to be rectified / filtered through a bridge rectifier made up of fast recovery diodes rated at around 25 amps 300V and 10uF / 400V capacitors.90003 90004 Converting 330 V DC into 50 Hz 220 V AC 90005 90002 Next, this rectified voltage which would now mount up to around 310V would need to be pulsed at the required 50 or 60 Hz through another full bridge inverter circuit as shown below: 90003 90002 The terminals marked “load” could be now directly used as the final output for operating the desired load. 90003 90002 Here the mosfets could be IRF840 or any equivalent type will do. 90003 90032 How to Wind the Ferrite Transformer TR1 90035 90002 The transformer TR1 is the main device which is responsible for stepping up the voltage to 220V at 5kva, being ferrite cored based it’s constructed over a couple of ferrite EE cores as detailed below: 90003 90002 Since the power involved is massive at around 5kvs, the E cores needs to be formidable in size, an E80 type ferrite E-core could be tried.90003 90002 Remember you may have to incorporate more than 1 E core, may be 2 or 3 E-cores together, placed side by side for accomplishing the massive 5KVA power output from the assembly. 90003 90002 Use the largest one that may be available and wind the 5 + 5 turns using 10 numbers of 20 SWG super enameled copper wire, in parallel. 90003 90002 After 5 turns, stop the primary winding insulate the layer with an insulating tape and begin the secondary 18 turns over this 5 primary turns. Use 5 strands of 25 SWG super enameled copper in parallel for winding the secondary turns.90003 90002 Once the 18 turns are complete, terminate it across the output leads of the bobbin, insulate with tape and wind the remaining 5 primary turns over it to complete the ferrite cored TR1 construction. Do not forget to join the end of the first 5 turns with the start of the top 5 turn primary winding. 90003 90032 E-Core Assembly Method 90035 90002 The following diagram gives an idea regarding how more than 1 E-core may be used for implementing the above discussed 5 KVA ferrite inverter transformer design: 90003 90002 E80 Ferrite core 90003 90032 Feedback from Mr.Sherwin Baptista 90035 90002 Dear All, 90003 90002 In the above project for the transformer, i did not use any spacers between the core pieces, the circuit worked well with the trafo cool while in operation. I always preferred an EI core. 90003 90002 I always rewound the trafos as per my calculated data and then used them. 90003 90002 All the more the trafo being an EI core, separating the ferrite pieces were rather easy than doing away with an EE core. 90003 90002 I also tried opening EE core trafos but alas; i ended up breaking the core while separating it.90003 90002 I never could open an EE core without breaking the core. 90003 90002 As per my findings, few things i would say in conclusion: 90003 90002 — Those power supplies with non-gaped core trafos worked best. (I am describing the trafo from an old atx pc power supply since i used those only. The pc power supplies do not fail that easily unless its a blown capacitor or something else.) — 90003 90002 — Those supplies that had trafos with thin spacers often were discolored and failed quiet early.(This i got to know by experience since till date i bought many second hand power supplies just to study them) — 90003 90002 — The much cheaper power supplies with brands like; CC 12v 5a, 12v 3a ACC12v 3a RPQ 12v 5a all 90003 90002 Such types ferrite trafos had thicker paper pieces between the cores and all failed poorly !!! — 90003 90002 In FINAL the EI35 core trafo worked the best (without keeping air gap) in the above project. 90003 90002 90007 5kva ferrite core inverter circuit preparation details: 90008 90003 90002 90007 Step 1: 90008 90003 90138 90139 Using 5 Sealed Lead Acid batteries of 12v 10Ah 90140 90139 Total voltage = 60v Actual voltage 90140 90139 = 66v fullcharge (13.2v each batt) voltage 90140 90139 = 69v Trickle level charge voltage. 90140 90147 90002 90007 Step 2: 90008 90003 90002 After calculation of battery voltage we have 66volts at 10 amps when full charged. 90003 90138 90139 Next comes the supply power to ic2153. 90140 90139 The 2153 has a maximum of 15.6v ZENER clamp betwen Vcc and Gnd. 90140 90139 So we use the famous LM317 to supply 13v regulated power to the ic. 90140 90147 90002 90007 Step 3: 90008 90003 90002 The lm317 regulator has the following packages; 90003 90168 90139 LM317LZ — 1.2-37v 100ma to-92 90140 90139 LM317T — 1.2-37v 1.5amp to-218 90140 90139 LM317AHV — 1.2-57v 1.5amp to-220 90140 90175 90002 We use the lm317ahv in which ‘A’ is the suffix code and ‘HV’ is the high volt package, 90003 90002 since the above regulator ic can support input voltage of upto 60v and output votage of 57 volts. 90003 90002 90007 Step 4: 90008 90003 90138 90139 We can not supply the 66v directly to the lm317ahv package sice its input is maximum of 60v. 90140 90139 So we employ DIODES to drop the battery voltage to a safe voltage to power the regulator.90140 90139 We need to drop about 10v safely from the maximum input of the regulator which is 60v. 90140 90139 Therefore, 60v-10v = 50v 90140 90139 Now the safe maximum input to the regulator from the diodes should be 50 volts. 90140 90147 90002 90007 Step 5: 90008 90003 90138 90139 We use the regular 1n4007 diode to drop the battery voltage to 50v, 90140 90139 Since being a silicon diode the voltage drop of each is about 0.7 volts. 90140 90139 Now we calculate the required number of diodes we need which would buck the battery voltage to 50 volts.90140 90139 battery voltage = 66v 90140 90139 calc.max input voltage to regulator chip = 50v 90140 90139 So, 66-50 = 16v 90140 90139 Now, 0.7 *? = 16v 90140 90139 We divide 16 by 0.7 which is 22.8 ie, 23. 90140 90139 So we need to incorporate about 23 diodes since the total drop from these amounts to 16.1v 90140 90139 Now, the calculated safe input voltage to the regulator is 66v – 16.1v which is 49.9v appxm. 50v 90140 90147 90002 90007 Step 6: 90008 90003 90138 90139 We supply the 50v to the regulator chip and adjust the output to 13v.90140 90139 For more protection, we use ferrite beads to cancel out any unwanted noise on the output voltage. 90140 90139 The regulator should be mounted on an appopriate sized heatsink in order to keep it cool. 90140 90139 The tantalum capacitor connected to the 2153 is an important capacitor that makes sure ic gets a smooth dc from the regulator. 90140 90139 Its value can be reduced from 47uf to 1uf 25v safely. 90140 90147 90002 90007 Step 7: 90008 90003 90138 90139 Rest of the circuit gets 66volts and the high current carrying points in the circuit should be wired with heavy guage wires.90140 90139 For the transformer its primary should be 5 + 5 turns and secondary 20 turns. 90140 90139 The frequency of the 2153 should be set at 60KHz. 90140 90147 90002 90007 Step 8: 90008 90003 90002 The High frequency ac to low frequency ac converter circuit using the irs2453d chip should be wired appropriately as shown in the diagram. 90003 90002 90007 Finally completed 90008. 90003 90038 Making a PWM Version 90039 90002 The following posting discusses another version of a 5kva PWM sinewave inverter circuit using compact ferrite core transformer.The idea was requested by Mr. Javeed. 90003 90004 Technical Specifications 90005 90002 90267 Dear sir, would you please modify its output with PWM source and facilitate to make use such an inexpensive and economical design to World wide needy people like us? Hope You will consider my request. Thanking you.Your affectionate reader. 90268 90003 90004 The Design 90005 90002 In the earlier post I introduced a ferrite core based 5kva inverter circuit, but since it is a square wave inverter it can not be used with the various electronic equipment, and therefore its application may be restricted to only with the resistive loads.90003 90002 However, the same design could be converted into a PWM equivalent sine wave inverter by injecting a PWM feed into the low side mosfets as shown in the following diagram: 90003 90002 90007 The SD pin of IC IRS2153 is mistakenly shown connected with Ct, please be sure to connect it with the ground line. 90008 90003 90002 Suggestion: the IRS2153 stage could be easily replaced with IC 4047 stage, in case the IRS2153 seems difficult to obtain. 90003 90002 As we can see in the above PWM based 5kva Inverter circuit, the design is exactly similar to our earlier original 5kva inverter circuit, except the indicated PWM buffer feed stage with the low side mosfets of the H-bridge driver stage.90003 90002 The PWM feed insertion could be acquired through any standard PWM generator circuit using IC 555 or by using transistorized astable multivibrator. 90003 90002 For more accurate PWM replication, one can also opt for a Bubba oscilator PWM generator for sourcing the PWM with the above shown 5kva sinewave inverter design. 90003 90002 The construction procedures for the above design is not different to the original design, the only difference being the integration of the BC547 / BC557 BJT buffer stages with the low side mosfets of the full bridge IC stage and the PWM feed into it.90003 90004 Another Compact Design 90005 90002 A little inspection proves that actually the upper stage does not need to be so complex. 90003 90002 The 310V DC generator circuit could be build using any other alternate oscillator based circuit. An example design is shown below where a half bridge IC IR2155 is employed as the oscillator in a push pull manner. 90003 90002 Again, there’s no specific design that may be necessary for the 310V generator stage, you can try any other alternative as per your preference, some common examples being, IC 4047, IC 555, TL494, LM567 etc.90003 90032 Inductor Details for the above 310V to 220V Ferrite Transformer 90035 90004 Ferrite Core Inverter Design using Transistor Astable Circuit 90005 90002 The following concept shows how a simple ferrite cored inverter could be built using a couple of ordinary transistor based astable circuit, and a ferrite transformer. 90003 90002 This idea was requested by a few of the dedicated followers of this blog, namely Mr. Rashid, Mr, Sandeep and also by a few more readers. 90003 90038 Circuit Concept 90039 90002 Initially I could not figure out the theory behind these compact inverters which completely eliminated the bulky iron core transformers.90003 90002 However after some thinking it seems I have succeeded in discovering the very simple principle associated with the functioning of such inverters. 90003 90002 Lately the Chinese compact type inverters have become pretty famous just because of their compact and sleek sizes which make them outstandingly light weight and yet hugely efficient with their power output specs. 90003 90002 Initially I thought the concept to be unfeasible, because according to me the use of tiny ferrite transformers for low frequency inverter application appeared highly impossible.90003 90002 Inverters for domestic use requires 50/60 Hz and for implementing ferrite transformer we would require very high frequencies, so the idea looked highly complicated. 90003 90002 After some thinking I was amazed and happy to discover a simple idea for implementing the design. Its all about converting the battery voltage to 220 or 120 mains voltage at very high frequency, and switching the output to 50/60 HZ using an push-pull mosfet stage. 90003 90004 How it Works 90005 90002 Looking at the figure we can simply witness and figure out the whole idea.Here the battery voltage is first converted to high frequency PWM pulses. 90003 90002 These pulses are dumped into a step up ferrite transformer having the required appropriate rating. The pulses are applied using a mosfet so that the battery current can be utilized optimally. 90003 90002 The ferrite transformer steps up the voltage to 220V at it output. However since this voltage has a frequency of around 60 to 100kHz, can not be directly used for operating the domestic appliances and therefore needs further processing.90003 90002 In the next step this voltage is rectified, filtered and converted to 220V DC. This high voltage DC is finally switched to 50 Hz frequency so that it may be used for operating the household appliances. 90003 90002 Kindly note that though the circuit has been exclusively designed by me, it has not been tested practically, make it at your own risk and on; y if you have sufficient confidence over the given explanations. 90003 90032 Circuit Diagram 90035 90032 Parts List for 12V DC to 220V AC compact ferrite core inverter circuit.90035 90138 90139 R3 — R6 = 470 Ohms 90140 90139 R9, R10 = 10K, 90140 90139 R1, R2, C1, C2 = calculate to generate 100kHz freq. 90140 90139 R7, R8 = 27K 90140 90139 C3, C4 = 0.47uF 90140 90139 T1 —- T4 = BC547, 90140 90139 T5 = any 30V 20Amp N-channel mosfet, 90140 90139 T6, T7 = any, 400V, 3 amp mosfet. 90140 90139 Diodes = fast recovery, high speed type. 90140 90139 TR1 = primary, 13V, 10amp, secondary = 250-0-250, 3amp. E-core ferrite transformer …. ask an expert winder and transformer designer for help.90140 90147 90002 An improved version of the above design is shown below. The output stage here is optimized for better response and more power. 90003 90032 Improved Version 90035 90032 About Swagatam 90035 90002 I am an electronic engineer (dipIETE), hobbyist, inventor, schematic / PCB designer, manufacturer. I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials. 90365 If you have any circuit related query, you may interact through comments, I’ll be most happy to help! 90003.90000 How to Make a Simple 200 VA, Homemade Power Inverter Circuit – Square Wave Concept 90001 90002 An efficiency of around 85% and a power output of more than 200 watts is what you will get from the present design of a power inverter (home built ). Complete circuit schematic and building procedure explained herein. 90003 90004 Introduction 90005 90002 You might have come across many articles regarding power inverters, however you might be still confused about making a power inverter? The present content provides a complete building tutorial of a home built power inverter.90003 90002 90003 90002 If you are planning to make your own low cost and simple home built power inverter then probably you will not find a better circuit than the present one. 90003 90002 This heavy duty, easy to build design includes very few numbers of components which can be found readily available in any electronic retailer shop. 90003 90002 The output of the inverter will be obviously a square wave and also load dependent. But these drawbacks will not matter much as long as sophisticated electronic equipment are not operated with it and the output is not over loaded.90003 90002 The big benefit of the present design is its simplicity, very low cost, high power output, 12 volt operation and low maintenance. Besides, once it is built, an instant start is pretty assured. 90003 90002 If at all any problem is encountered, troubleshooting will not be a headache and may be traced within minutes. The efficiency of the system is also pretty high, in the vicinity of around 85% and the output power is above 200 watts. 90003 90002 A simple two transistor astable multivibrator forms the main square wave generator.The signal is suitably amplified by two current amplifier medium power Darlington transistors. 90003 90002 This amplified square wave signal is further fed to the output stage comprising of parallel connected high power transistors. These transistors convert this signal into high current alternating pulses which is dumped into the secondary windings of the power transformer. 90003 90002 The induced voltage from the secondary to the primary winding, results a massive 230 or 120 volts conversion, as per transformer specifications.90003 90002 Let’s study in details how the circuit functions. 90003 90002 90003 90030 Circuit Operation 90031 90002 The circuit diagram description of this home built power inverter may be simply understood through the following points: 90003 90002 Transistor T1 and T2 along with C1 and C2 and the other associated parts forms the required astable multivibrator and heart of the circuit. 90003 90002 The relatively weak square wave signals generated at the collector of T1 and T2 is applied to the base of the driver transistors T2 and T3 respectively.These are specified as Darlington pairs and thus very effectively amplify the signals to suitable levels so that they may be fed to the high power output transistor configuration. 90003 90002 On receiving the signal from T2 and T3, all parallel output transistors saturate well enough according to the varying signal and create a huge push pull effect in the secondary windings on the power transformer. This alternate switching of the entire battery voltage through the windings induce massive step up power into the primary windings of the transformer producing the desired AC output.90003 90002 The resistors placed at the emitter of the 2N3055 transistors are all 1 Ohm, 5 Watts and has been introduced to avoid thermal runaway situations with any of the transistors. 90003 90002 90003 90002 90003 90002 90003 90002 PARTS LIST 90003 90002 RESISTORS ¼ WATT, CFR 90003 90002 R1, R4 = 470 Ω, 90003 90002 R2, R3 = 39 K, 90003 90002 RESISTORS, 10 WATT, WIRE WOUND 90003 90002 R5, R6 = 100 Ω, 90003 90002 R7 —– R14 = 15 Ω, 90003 90002 R15 —- R22 = 0.22 Ohms, 5 watt (can be connected directly if all the parallel transistors are mounted on a common heatsink, separate for each channel) 90003 90002 Capacitors 90003 90002 C1, C2 = 0.33 μF, 50 VOLTS, TANTALLUM, 90003 90002 Semiconductors 90003 90002 D1, D2 = 1N5408, 90003 90002 T1, T2 = BC547B, 90003 90002 T3, T4 = TIP 127, 90003 90002 T5 —– T12 = 2N 3055 POWER TRANSISTORS , 90003 90002 Misc. 90003 90002 TRANSFORMER = 10 to 20 AMPS, 9 – 0 – 9 VOLTS, 90003 90002 HEATSINKS = LARGE FINNED TYPE, 90003 90002 BATTERY = 12 VOLT, 100 AH 90003 90002 90003 90030 Inverter Building Tutorial 90031 90002 The below given discussion should provide you with a detailed step wise explanation regarding how to build your own power inverter: 90003 90002 WARNING: The present circuit involves dangerous Alternating Currents, extreme Caution is advised.90003 90002 The only part of the circuit which is probably difficult to procure is the transformer, because a 10 Amp rated transformer is not easily available in the market. In that case you can get two 5 Amp rated transformers (easily available) and connect their secondary taps in parallel. 90003 90002 90003 90002 Do not connect their primary in parallel; rather divide them as two separate outputs (See Image and Click to Enlarge). 90003 90002 Next difficult stage in the building procedure is the making of the heat sinks.I will not recommend you to fabricate them by yourself as the task can be quite a tedious one and time consuming too. It would be rather a better idea to get them ready made. You will find variety of them, in different sizes in the market. 90003 90030 2N3055 Pinout Diagram 90031 90002 90003 90002 Select the suitable ones; make sure that the holes are appropriately drilled for the TO-3 package as shown in the figure. TO-3 is the code to recognize typically the dimensions of power transistors which are categorized in the type used in the present circuit i.e. for 2N3055. 90003 90002 Fix T5 —- T8 firmly over the heat sinks using 1/8 * 1/2 screws, nuts and spring washers. You may use two separate heat sinks for the two sets of transistors or one single large heat sink. Do not forget to isolate the transistors from the heat sink with the help of mica isolation kit. 90003 90030 TIP127 Pinout Diagram 90031 90002 90003 90002 Constructing the PCB is just a matter of putting all the components in place and interconnecting their leads as per the given circuit schematic.It can be done simply over a piece of general PCB. 90003 90002 Transistors T3 and T4 also need heat sinks; a “C” channel type aluminum heat sink will do the job perfectly. This is can also be procured ready made as per the given size. 90003 90002 Now we can connect the relevant points from the assembled board to the power transistors fitted over the heat sinks. Take care of its base, emitter and the collector, a wrong connection would mean an instant damage of the particular device. 90003 90002 Once all the wires are connected appropriately to the required points, lift the whole assembly gently and place it on the base of a strong and sturdy metallic box.The size of the box should such that the assembly does not get crammed. 90003 90002 It goes without saying that the outputs and the inputs of circuit should be terminated into proper socket type of outlets, to make the external connections easy. The external fittings should also include a fuse holder, LEDs and a toggle switch. 90003 90030 How to Test 90031 90126 90127 Testing this home built inverter is very simple. It may be done in the following ways: 90128 90127 Insert the specified fuse into the fuse holder.90128 90127 Connect a 120/230 volt 100 Watt incandescent lamp in the output socket, 90128 90127 Now take a fully charged 12V / 100Ah lead acid battery and connect its poles to the inverter supply terminals. 90128 90127 If everything is connected as per the given schematic, the inverter should instantly start functioning illuminating the bulb very brightly. 90128 90127 For your satisfaction you may check the current consumption of the unit through following the simple steps: 90128 90127 Take a digital multimeter (DMM), select 20A current range in it.90128 90127 Remove the inverter fuse from its fuse holder, 90128 90127 Clip the DMM’s prods into the fuse terminals such that the DMM’s positive prod links with the battery positive. 90128 90127 Switch on the inverter, the consumed current will be instantly displayed over the DMM. If you multiply this current with the battery voltage i.e. by 12, the result will give you the consumed input power. 90128 90127 Similarly, you may find the output consumed power through the above procedure (DMM set in the AC range).Here you will have to multiply the output current with the output voltage (120 or 230) 90128 90127 By dividing output power by the input power and multiplying the result by 100, will immediately give you the efficiency of the inverter. 90128 90127 If you have any questions regarding how to build your own power inverter, feel free to comment (comments need moderation, may take time to appear). 90128 90153 90154 About Swagatam 90155 90002 I am an electronic engineer (dipIETE), hobbyist, inventor, schematic / PCB designer, manufacturer.I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials. 90157 If you have any circuit related query, you may interact through comments, I’ll be most happy to help! 90003.90000 3 Best Transformerless Inverter Circuits 90001 90002 As the name suggests, an inverter circuit that converts a DC input into AC without depending on an inductor or a transformer is called a transformerless inverter. 90003 90002 Since an inductor based transformer is not employed, the input DC is normally equal to the peak value of the AC generated at the output of the inverter. 90003 90002 The post helps us to understand 3 inverter circuits designed to work without using a transformer, and using a full bridge IC network and a SPWM generator circuit.90003 90008 Transformerless Inverter using IC 4047 90009 90002 Let’s begin with an H-Bridge topology that’s probably the simplest in its form. However, technically it’s not the ideal one, and not recommended, since It is designed using p / n-channel mosfets. P-channel mosfets are used as the high side mosfets, and n-channel as the low side. 90003 90002 Since, p-channel mosfets are used on the high side, the bootstrapping becomes unnecessary, and this simplifies the design a lot. This also means this design does not have to depend on special driver ICs.90003 90002 Although the design looks cool and enticing, it has a few underlying disadvantages. And that’s exactly why this topology is avoided in professional and commercial units. 90003 90002 That said, if it’s built correctly may serve the purpose for low frequency applications. 90003 90002 Here’s the complete circuit using IC 4047 as the astable totem pole frequency generator 90003 90020 90021 Parts List 90022 90023 90002 All resistors are 1/4 watt 5% 90003 90026 90027 R1 = 56k 90028 90027 C1 = 0.1uF / PPC 90028 90027 IC pin10 / 11 resistor = 330 ohms – 2nos 90028 90027 MOSFET gate resistors = 100k – 2nos 90028 90027 Opto-couplers = 4N25 – 2 nos 90028 90027 Upper P-channel MOSFETs = FQP4P40 – 2nos 90028 90027 Lower N- Channel MOSFETs = IRF740 = 2nos 90028 90027 Zener diodes = 12V, 1/2 watt – 2 nos 90028 90043 90002 The next idea is also an h-bridge circuit but this one uses the recommended n-channel mosfets. The circuit was requested by Mr. Ralph Wiechert 90003 90008 Main Specifications 90009 90002 90049 Greetings from Saint Louis, Missouri.90050 90051 90049 Would you be willing to collaborate on an inverter project? I would pay you for a design and / or your time, if you’d like. 90050 90003 90002 90049 I have a 2012 & 2013 Prius, and my mother has a 2007 Prius. The Prius is unique in that it has a 200 VDC (nominal) high-voltage battery pack. Prius owners in the past have tapped into this battery pack with off-the-shelf inverters to output their native voltages and run tools and appliances. (Here in the USA, 60 Hz, 120 & 240 VAC, as I’m sure you know).The problem is those inverters are no-longer made, but the Prius is still is. 90050 90003 90002 90049 Here are a couple inverters that were used in the past for this purpose: 90050 90003 90002 90049 1) PWRI2000S240VDC (See attachment) No longer manufactured! 90050 90003 90002 90049 2) Emerson Liebert Upstation S (This is actually a UPS, but you remove the battery pack, which was 192 VDC nominal.) (See attachment.) No longer manufactured! 90050 90003 90002 90049 Ideally, I’m looking to design a 3000 Watt continuous inverter, pure sine wave, output 60 Hz, 120 VAC (with 240 VAC split phase, if possible), and transformer-less.Perhaps 4000-5000 Watts peak. Input: 180-240 VDC. Quite a wish-list, I know. 90050 90003 90002 90049 I am a mechanical engineer, with some experience building circuits, as well as programming Picaxe micro-controllers. I just do not have much experience designing circuits from scratch. I’m willing to try & to fail, if needed! 90050 90003 90008 The Design 90009 90002 In this blog I have already discussed more than 100 inverter designs and concepts, the above request can be easily accomplished by modifying one of my existing designs, and tried for the given application.90003 90002 For any transformerless design there has to be a couple of basic things included for the implementation: 1) The inverter must be a full bridge inverter using a full bridge driver and 2) the fed input DC supply must be equal to the required output peak voltage level. 90003 90002 Incorporating the above two factors, a basic 3000 watt inverter design can be witnessed in the following diagram, which has a 90021 pure sinewave output waveform 90022 feature. 90003 90002 The functioning details of the inverter can be understood with the help of the following points: 90003 90002 The basic or the standard full bridge inverter configuration is formed by the full bridge driver IC IRS2453 and the associated mosfet network.90003 90093 Calculating the Inverter Frequency 90094 90002 The function of this stage is to oscillate the connected load between the mosfets at a given frequency rate as determined by the values ​​of the Rt / Ct network. 90003 90002 The values ​​of these timing RC components can be set by the formula: f = 1 / 1.453 x Rt x Ct where Rt is in Ohms and Ct in Farads. It should be set for achieving 60Hz for complementing the specified 120V output, alternatively for 220V specs this could be changed to 50Hz.90003 90002 This may be also achieved through some practical trial and error, by assessing the frequency range with a digital frequency meter. 90003 90002 For achieving a pure sinewave outcome, the low-side mosfets gates are disconnected from their respective IC feeds, and are applied the same through a BJT buffer stage, configured to operate through an SPWM input. 90003 90093 Generating SPWM 90094 90002 The SPWM which stands for sinewave pulse width modulation is configured around an opamp IC and a single IC 555 PWM geneartor.90003 90002 Although the IC 555 are configured as PWM, the PWM output from its pin # 3 is never used, rather the triangle waves generated across its timing capacitor is utilized for the carving of the SPWMs. Here one of the triangle wave samples is supposed to be much slower in frequency, and synchronized with the main IC’s frequency, while the other needs to be faster triangle waves, whose frequency essentially determines the number of pillars the SPWM may have. 90003 90002 The opamp is configured like a comparator and is fed with triangle wave samples for processing out the required SPWMs.One triangle wave which is the slower one is extracted from the Ct pinout of the main IC IRS2453 90003 90002 The processing is done by the opamp IC by comparing the two triangle waves at its input pinouts, and the generated SPWM is applied to the bases of the BJT buffer stage. 90003 90002 The BJTs buffers switch according to the SPWM pulses and make sure that the low side mosfets are also switched at the same pattern. 90003 90002 The above switching enables the output AC also to switch with an SPWM pattern for both the cycles of the AC frequecny waveform.90003 90093 Selecting the mosfets 90094 90002 Since a 3kva transformerless inverter is specified, the mosfets need to be rated appropriately for handling this load. 90003 90002 The mosfet number 2SK 4124 indicated in the diagram will actually not be able to sustain a 3kva load because these are rated to handle a maximum of 2kva. 90003 90002 Some research on the net allows us to find the mosfet: 90021 IRFB4137PBF-ND 90022 which looks good for operating over 3kva loads, due to its massive power rating at 300V / 38amps.90003 90002 Since it is a transformerless 3kva inverter, the question of selecting transformer is eliminated, however the batteries must be appropriately rated to produce a minimum of 160V while moderately charged, and around 190V when fully charged. 90003 90093 Automatic Voltage Correction. 90094 90002 An automatic correction can be achieved by hooking up a feedback network between the output terminals and the Ct pinout, but this may be actually not required because the IC 555 pots can be effectively used for fixing the RMS of the output voltage, and once set the output voltage can be expected to be absolutely fixed and constant regardless of the load conditions, but only as long as the load does not exceed the maximum power capacity of the inverter.90003 90093 2) Transformerless Inverter with Battery Charger and Feedback Control 90094 90002 The second circuit diagram of a compact transformeress inverter without incorporating bulky iron transformer is discussed below. Instead of an heavy iron transformer it uses a ferrite core inductor as shown in the following article. The schematic is not designed by me, it was provided to me by one of the avid readers of this blog Mr. Ritesh. 90003 90002 The design is a full fledged configuration with includes most of the features such as ferrite transformer winding details, low voltage indicator stage, output voltage regulation facility etc.90003 90002 The explanation for the above design has not been updated yet, I will try to update it soon, in the meantime you can refer the diagram and get your doubts clarified through comment, if any. 90003 90008 200 watt Compact Transformerless Inverter Design # 3 90009 90002 A third design below shows a 200 watt inverter circuit without a transformer (transformerless) using a 310V DC input. It is a sine wave compatible design. 90003 90093 Introduction 90094 90002 Inverters as we know are devices which convert or rather invert a low voltage DC source to a high voltage AC output.90003 90002 The produced high voltage AC output is generally in the order of the local mains voltage levels. However the conversion process from a low voltage to high voltage invariably necessitates the inclusion of hefty and bulky transformers. Do we have an option to avoid these and make a transformerless inverter circuit? 90003 90002 Yes there is a rather very simple way of implementing a transformerless inverter design. 90003 90002 Basically inverter utilizing low DC voltage battery require to boost them to the intended higher AC voltage which in turn makes the inclusion of a transformer imperative.90003 90002 That means if we could just replace the input low voltage DC with a DC level equal to the intended output AC level, the need of a transformer could be simply eliminated. 90003 90002 The circuit diagram incorporates a high voltage DC input for operating a simple mosfet inverter circuit and we can clearly see that there’s no transformer involved. 90003 90093 Circuit Operation 90094 90002 The high voltage DC equal to the required output AC derived by arranging 18 small, 12 volt batteries in series.90003 90002 The gate N1 is from the IC 4093, N1 has been configured as the oscillator here. 90003 90002 Since the IC requires a strict operating voltage between 5 and 15 volts, the required input is taken from one of the 12 volt batteries and applied to the relevant IC pin outs. 90003 90002 The entire configuration thus becomes very simple and efficient and completely eliminates the need of a bulky and heavy transformer. 90003 90002 The batteries are all 12 volt, 4 AH rated which are quite small and even when connected together does not seem to cover too much of space.They may stacked tightly to form a compact unit. 90003 90002 The output will be 110 V AC at 200 watts. 90003 90020 Parts List 90023 90026 90027 Q1, Q2 = MPSA92 90028 90027 Q3 = MJE350 90028 90027 Q4, Q5 = MJE340 90028 90027 Q6, Q7 = K1058, 90028 90027 Q8, Q9 = J162 90028 90027 NAND IC = 4093, 90028 90027 D1 = 1N4148 90028 90027 Battery = 12V / 4AH, 18 nos. 90028 90043 90008 Upgrading into a Sinewave Version 90009 90002 The above discussed simple 220V transformerless inverter circuit could be upgraded into a pure or true sinewave inverter simply by replacing the input oscillator with a sine wave generator circuit as shown below: 90003 90002 Parts List for the sinewave oscillator can be found in this post 90003 90008 Transformerless Solar Inverter Circuit 90009 90002 Sun is a major and an unlimited source of raw power which is available on our planet absolutely free.This power is fundamentally in the form of heat, however humans have discovered methods of exploiting the light also from this huge source for manufacturing electrical power. 90003 90093 Overview 90094 90002 Today electricity has become the life line of all cities and even the rural areas. With depleting fossil fuel, sun light promises to be one of the major renewable source of energy that can be accessed directly from anywhere and under all circumstances on this planet, free of cost. Let’s learn one of the methods of converting solar energy into electricity for our personal benefits.90003 90002 In one of my previous posts I have discussed a solar inverter circuit which rather had a simple approach and incorporated an ordinary inverter topology using a transformer. 90003 90002 Transformers as we all know are bulky, heavy and may become quite inconvenient for some applications. 90051 In the present design I have tried to eliminate the use of a transformer by incorporating high voltage mosfets and by stepping up the voltage through series connection of solar panels. Let’s study the whole configuration the with the help of the following points: 90003 90093 How it Works 90094 90002 Looking at the below shown solar based transformerless inverter circuit diagram, we can see that it basically consists of three main stages, viz.the oscillator stage made up of the versatile IC 555, the output stage consisting of a couple of high voltage power mosfets and the power delivering stage which employs the solar panel bank, which is fed at B1 and B2. 90003 90093 Circuit Diagram 90094 90002 Since the IC can not operate with at voltages more than 15V, it is well guarded through a dropping resistor and a zener diode. The zener diode limits the high voltage from the solar panel at the connected 15V zener voltage. 90003 90002 However the mosfets are allowed to be operated with the full solar output voltage, which may lie anywhere between 200 to 260 volts.On overcast conditions the voltage might drop to well below 170V, So probably a voltage stabilizer may be used at the output for regulating the output voltage under such situations. 90003 90002 The mosfets are N and P types which form a pair for implementing the push pull actions and for generating the required AC. 90003 90002 The mosfets arenot specified in the diagram, ideally they must be rated at 450V and 5 amps, you will come across many variants, if you google a bit over the net. 90003 90002 The used solar panels should strictly have an open circuit voltage of around 24V at full sunlight and around 17V during bright dusk periods.90003 90008 How to Connect the Solar Panels 90009 90093 Parts List 90094 90002 R1 = 6K8 90051 R2 = 140K 90051 C1 = 0.1uF 90051 Diodes = are 1N4148 90051 R3 = 10K, 10 watts, 90051 R4, R5 = 100 Ohms, 1/4 watt 90051 B1 and B2 = from solar panel 90051 Z1 = 5.1V 1 watt 90003 90002 Use these formulas for calculating R1, R2, C1 …. 90003 90002 Update: 90003 90002 The above 555 IC design may not be so reliable and efficient , a much reliable design can be seen below in the form of a full H-bridge inverter circuit.This design can be expected of providing much better results than the above 555 IC circuit 90003 90002 Another advantage of using the above circuit is that you will not require a dual solar panel arrangement, rather a single series connected solar supply would be enough to operate the above circuit for achieving a 220V output. 90003 90020 About Swagatam 90023 90002 I am an electronic engineer (dipIETE), hobbyist, inventor, schematic / PCB designer, manufacturer. I am also the founder of the website: https: // www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials. 90051 If you have any circuit related query, you may interact through comments, I’ll be most happy to help! 90003.