Inverter 12V to 220V 100W by Transistor

This circuit is 100 watt power inverter using power transistor 2N3055. It is designed for you that need to use appliances at outdoor or no electrical places. Someone use it in car or the high mountain etc.

The maximum output power of this circuit about 100 watts, it is suitable for a normal lighting (all home lamps), also used for radio, mini TV, stereo or someone use it for
How it works
From the schematic diagram in Figure 1 this circuit will include of 4 main section are:
1. The transistors Q1,Q2 act as the frequency oscillator circuit.
2. Both transistors Q3,Q4 act as the frequency divider circuit
3. The Q5,Q6 act as the driver circuit.
4. The Q7,Q8 act as the output circuit.

Let’s look at to both transistors Q1,Q2 will be connected together as the astable multivibrator form. It will generate the output frequency about 100 Hz at the collector lead of Q2. Then this signal will sent to the two frequency divider makes the frequency is reduced down about 50Hz

Cause we don’t design the circuit to directly work at 50 Hz. Because the generating the steady low frequency is very hard.

The output from divider circuit is sent to base of Q5,Q6. To increase current up to drive the output transistors Q7,Q8, then drive the transformer, finally to supply load.
1. Normally, use the 2-3A transformers for 20-30watt for the incandescent lamp. But use need 100watt use must use 8A transformer so expensive for me.
2. The primary coil of transformer use may use 9V CT 9V or 10V ct 10V or 12V ct 12V.
Which normal I use 12V ct 12V makes the output voltage about AC 220V (no load). But there is load voltage will reduce to AC190V
3.This circuit will has output as square wave form. So cannot use for inductor load.
4. This transformer, we may use secondary coil is the output voltage as you need, example we connects to the power amplifier that use AC 24 volts so we use AC 24V secondary coil etc.

How to builds.
It is like all our projects. To begin with make the PCB or you can use the universal PCB. Then, assemble all part on PCB as Figure 2. Next check all for error. Check again and check again.

Then apply the 12V 10A battery to this circuit and use the voltmeter to measure AC voltage output. Next connects load to the circuit.

Figure 1 Circuit diagram of Inverter 12V to 220V 100W by Transistor

Figure 2 PCB layout and components layouts of the 100 Watts Inverter, 12V to 220V by Transistors

Parts you will need

Q1-Q4______BC557___45V 100mA PNP Transistor
Q5,Q6______BD139___80V 1.5A NPN Transistor
Q7,Q8______2N3055___100V, 15A, 115W, >2,5MHz NPN transistor
D1,D2,D3,D4_____1N4148______75V 150mA Diodes
D5,D6_______1N4007 __1000V 1A Diodes
R1,R4,R6,R7_________10K___1/2W Resistors tolerance: 5%
R2,R3___________150K______1/2W Resistors tolerance: 5%
R5,R6___________ 47K______1/2W Resistors tolerance: 5%
R9,R12__________ 220 ohms 1/2W Resistors tolerance: 5%
R10,R13_________ 560 ohms 1/2W Resistors tolerance: 5%
R11, R14________ 100K ____1/2W Resistors tolerance: 5%
R15, R16________ 10 ohms__10W Resistors tolerance: 5%
R17, R18________ 150 ohms_1/2W Resistors tolerance: 5%
C1,C2___________0.047uF 50V_____Ceramic capacitors
C3,C4__________0.01uF 50V____Ceramic capacitors
C5______________1uF 50V_____ Ceramic capacitors
C6_____________0.1uF 250V____ Ceramic capacitors
C7_____________0.1uF 50V_____ Ceramic capacitors
C8____________220uF 25V_______ Electrolytic capacitors
T1___230V AC primary to 12V-0-12V,2-8A secondary transformer.

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  1. moath abdo February 18, 2017
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