inverter circuit using ir2101

[pakkiboy]

Dear members,
I have designed full bridge pure sine wave inverter using IR2101 with specs
Mosfets : irf740
mosfet driver : 2101
boostrap capacitor : 67 Uf
Gate to source res : 1 Kohm
main issue when i give about 125 DC to mosfet drain , pure sine wave produced
but when i give 300 V DC dirctly to make 220 V AC , sparking produced in MOSFETs ??? any idea how to overcome this issue ?? plz help
Thanks alot

 

[ted]

You are not given enough information for anybody to answer your question.
As minimum, you should post the schematics of the circuit.