I Have a big problam !!......with Inverter 12VDC to 220VAC

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in my project the capacitors always overheat and explode ( i us in 160V 68uF ) what can i do that the capacitors don't overheat and explode....????

the parts:
R1,R2 = 10 ohm, 5 watt
R3,R4 = 180 ohm, 1 watt
C1,C2 = 68uF, 50 Volt (or higher volt)
D1,D2 = 1N4002
Q1,Q2 = 2N3055
T1 = 220 / 24ct Transformer


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You probably want to delete R1, R2, D1 and D2 too.

Its about 50/60 hz, and is definitely NOT a sine wave.
Exact frequency depends on the transformer.

Very similar to the heathkit inverters of years ago...

What do you want to do with it???

With the transistors specified it is good for about 200 watts
I agree. You are going the wrong way down a one-way street...and there's no exits for miles. The schematic, either one, will not be high enough power to do what you want it to do and I recommend just getting a car stereo amplifier. As a side bar though: The home equipment should work fine with a squarewave 50/60 Hz but it is not recommended. The original schematic was an attempt at a astable multivibrator, also called an emmiter-couple oscillator. The "fix" was an attempt to change it into a similar circuit called an Royer oscillator. A "Royer oscillator" is a low power converter type circuit. Usually working a few kilohertz to a few tens of kHz. This would not be the type of circuit t use for a 12V automoblie system. You need a supply that is regulated and used a full-bridge configuration.

Your best bet is then to take out the powe supply that is in the amplifier now and design a converter for it. You will need to know the rail voltages for the amplifier channels. Otherwise, you are going DC to AC to DC again. That is 12VDC to 230AC to DC rails. This is a complete waste of a lot of things...space, energy, time, weight. Try designing a 12V-to-split symmetrical rails power supply. Then you can evaluate the amplifier channels in the car. That is the best advice that I can give to you. Also, none of the circuits shown will be able to work for a few reasons...the circuit frewheels at a constant frequency and duty cylce based on the number of turns and the saturation time for the transistor, it is unregulated, it wont be able to deliver enough current for an amplifier to run. You will have to go to a more complicated circuit. That circuit is good if you need a medium power oscillator.

To get 280 watts from 12 volts you will need 25 amps from your 12 volt power source. That assumes near 100% efficiency.

Throw in some real world losses of the above mentioned DC to AC to DC conversion and you get to the, "Just buy a 12 volt car amp" answer real quick.

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