How to Make a Transformerless Solar Inverter Circuit

Sun is a significant and a limitless source of raw power which is accessible on our planet freely available. This power is simply by means of heat, in spite of this humans have found techniques of taking advantage of the light also from this huge source for producing electrical power.

These days electricity is becoming the everyday living line of all cities and even the rural areas. With draining fossil fuel, sun light guarantees to be one of the major alternative source of energy which might be found instantly from any shade and under all situations around the world, free of cost. Let’s learn certainly one of the ways of transforming solar energy into electricity for our individual advantages.

In one of my earlier articles I possess mentioned a solar inverter circuit which quite had a basic approach and integrated a regular inverter topology utilizing a transformer.
Transformers as we all know are large, weighty and could become quite annoying for certain functions.
In the existing design I have attempted to get rid of the utilization of a transformer by including high voltage mosfets and by upgrading the voltage by means of series connection of solar panels. Let’s research the complete design the with the aid of the following points:

Considering the circuit diagram, we are able to observe that it essentially includes three main phases, viz. the oscillator phase comprised of the adaptable IC 555, the output period comprise of several high voltage power mosfets and the power providing phase which uses the solar panel bank, which can be fed at B1 and B2.


220v, 120v transformerless solar inverter circuit

220v, 120v transformerless solar inverter circuit

Considering that the IC are not able to function with at voltages a lot more than 15V, it is well guarded by way of a reducing resistor and a zener diode. The zener diode limitations the high voltage from the solar panel at the linked 15V zener voltage.

In spite of this the mosfets are able to be controlled with the full solar output voltage, which can lie somewhere between 200 to 260 volts. On overcast problems the voltage may decrease to well below 170V, So possibly a voltage stabilizer can be utilized at the output for regulating the output voltage under such circumstances.

The mosfets are N and P kinds which form a pair for employing the push pull actions and for producing the needed AC.

The mosfets arenot specific in the diagram, preferably they needs to be scored at 450V and 5 amps, you will discover many versions, if you google a bit over the net.

The utilized solar panels should purely have an open circuit voltage of around 24V at full sunlight and around 17V during bright dusk periods.


Parts List

R1 = 6K8
R2 = 140K
C1 = 0.1uF
Diodes = are 1N4148
R3 = 10K, 10 watts,
R4, R5 = 100 Ohms, 1/4 watt
B1 and B2 = from solar panel
Z1 = 5.1V 1 watt

Use these formulas for calculating R1, R2, C1….