400Khz 600W H-bridge

[naserim]

Hello guys

As a part of my school project I'm working on a 400khz power inverter. I need the output current to be 18A. supply voltage is 40V.
I've tested many circuits and I considered IR2113 mosfet driver as the solution. The inverter works well in low duty cycles while the current is about 4A however when the pulse width increases one of mosfets starts to heat up and after a few seconds all mosfets burn.
I've tested IRF3205 and IRFp150.
I'm really disappointed.
Please help me.

I've used the ir2113 datasheet circuit with 10uf caps and uf4007 diode. all Fets are Nchannel.

- - - Updated - - -

**broken link removed**

this is the 2113 circuit. each 2113 drives two mosfets which are turned on simultaneously. connectors are connected to high side fet gate, high side fet source and low side fet gate.

 

[Anna Conda]

400kHz may well be too fast for the 2113, the gate drive may not be up to it at these frequencies, you would need a discrete buffer between the 2113 and the fets, and a very well designed high speed, low impedance turn off gate drive (12V to 0v in <40nS) at this freq of operation.
Also unless you have an inductive load allowing zero volt turn on of the mosfets then the hard switching losses in the mosfets will be quite high, possibly leading to their destruction at high loads, this is not a trivial design.
Regards, Dr. AC. power electronics engineer.

 

[FvM]

IR2113 can possibly still work at 400 kHz, but surely not drive the required low gate resistors without additional buffers, e.g. BJT emitter followers.

Did you estimate switching losses and required gate drive in advance? You should also observe the effect of source inductance, that basically limits the achievable switching speed in low voltage/high current circuits.

 

[mtwieg]

Your attachment isn't working for me.

What kind of load are you trying to drive? Are you doing SPWM, or are you just driving the load with a 400KHz square wave with constant duty cycle?