A power inverter is a very useful device that can convert Low voltage from a DC source to high voltage AC. The most common power inverter is a 12V to 240V inverter. Perhaps that is because 12V batteries are common. This type of power inverter usually draws a high current from a DC battery so the battery should be able to supply a high flow of electric current for a long time. Normally lead acid batteries can serve this purpose very well. This current is then converted to a 240V square wave alternative current so that we can power up 220V to 240V electric appliances.
Inverter falls in the category of expensive devices so many people don’t buy it even if they need it. What if I tell you how to build an inverter yourself?
I remember when I build my first inverter, I became so happy that I invited all my friends to see my homemade inverter. I am sure you will feel the same after building it.
Caution: This circuit involves 240V and 500W which can be fatal. You should take all security precautions before building this circuit. Preferably use electricity protective gloves and try not to play with the inverter circuit when it is operational. You must have the necessary knowledge of electronics to build this circuit.
Alright, let us get to work. There are a lot of inverter circuit diagrams available online. Some of them are complex and others are low-performance. I have researched a lot of them but in the end, I had to design my inverter circuit. It is comparable to any professionally made inverter but still is simple enough for you to build.
Here is the inverter circuit diagram. It is better to print this entire page and keep it with you while building the inverter.
Expected Cost: It took me less than $100 to complete this circuit.
You will need the following parts.
There is only one variable resistance in this circuit diagram which is used to adjust the frequency of 240V AC output current. You should have a frequency meter to adjust this frequency from 50HZ to 60HZ as per your requirement. Please do not power up any device with your inverter before frequency adjustment. A wrong AC frequency can easily burn your equipment as well as your inverter.
I have used a two-stage regulated power supply to avoid frequency changes with the drop in battery voltage. The first stage is 7809 which is a standalone voltage regulator. It converts 12V DC to 9V DC. Then we used a 22 Ohm resistor and then a Zener diode of 8.2V which forces the current to stay at 8.2V. The 22 Ohm resistor is there just to aid the Zener diode.
The output frequency of this inverter circuit is a square wave which is not ideal to power up inductive loads. If you want to power up any inductive load then use it at your own risk. However, I do power up fans at home using this inverter. The only issue I had with them was a little decrease in the fan speed and the addition of some humming noise.
If you have any questions, please use the comment box bellow.