modified sine wave smps inverter

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I have generated 311vdc from 12vdc, now my aim is to convert this dc bus into modified sine wave with the help of full bridge and sg3525 ic ..please tell me how to proceed..I have also made full bridge circuit ..so how to drive the 4inputs of full bridge from sg3525 in order to get modified sine wave at the output.
 

This method appears to work in simulation.

It allows low-volt control signals to be compatible with the high voltage supply.



To produce a modified sine wave, the two control signals are 25% duty cycle, staggered 180 degrees.

None of the bias network resistors has to carry more than 20 mA.

The wires cross above the load, so as to allow a less congested wiring layout.
 

My schematic is to illustrate the concept.

The mosfets/transistors should be selected to endure the maximum voltage/current they will be exposed to. (Rather, make it 2X the maximum, to give a safety margin.)

The resistor values need to be low enough to provide sufficient bias current to transistors. But high enough so they do not permit more than is necessary. Notice that you need to pay attention to the amount of current that might flow out of the PNP bias down into the NPN bias.

IRF740 mosfets are popular N-type.
For the P-type it is suitable to use one with about the same V and A rating.

My schematic does not show the devices used to generate the clock signals. To do that will require an independent circuit.
 
how to connect LC filter?
Click to expand...

This suggests you now want a sinewave output, rather than your original specification for a modified sine wave.

If you wish to add an LC filter, it is better to apply it to AC square waves rather than modified sine waves.

With a modified sine wave, the mosfets/transistors are off during part of the cycle. You cannot use a series LC arrangement.

You can arrange the coil and cap as a second order filter.

Screenshot:

 
It is Falstad's interactive animated simulator. A free download at falstad.com/circuit.

The link below will open his website, load my schematic above, and run it on your computer:

https://tinyurl.com/kl95lft

You can alter values. Right-click on a component, and select Edit.

You can save a circuit. Click File, select Export. A text window appears. Copy the text and paste it into a word processor. Save the document.
 
Assalamoalaikum Hamid,

Please let me know if you can make any inverter,if yes, please tell me its power rating.
 

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