Problems with my inverter at high voltage... can't go higher than 3.3v!!

[Orson Cart]

IR2117 looks OK.

VBSD1-S15-S15-SIP 15V to 15V 1kV isolation looks OK but has a min load requirement on the ouput,so you will need a 1watt 16V zener on its o/p to keep the volts below 16.

Yes, you can use the IR2110, but if you have 8 fets on each side you will need 7 IR2110's for each side as you can only use the low side part for the 0V connected fets. you can only use the high side part for the 7 upper fets.

Regards, Orson Cart.

 

[mtwieg]

For a multilevel converter, the most cost effective option would be a plain 60Hz stepdown transformer with many secondaries, and just bridge rectify the outputs. It's not like you need good regulation on the gate drive anyways. Using little switcher modules for each FET is going to be very expensive.

 

[yokahu]

Hello,

the components i ordered have finally arrived. I'll be posting the results in a few days.

They were a little expensive since i have 16 FETs but for the first prototype is acceptable imo.

 

[yokahu]

Hi,

I finally was able to make my nine level flying capacitor multilevel work properly; its running fine with a THD of 14.5%.

Now time to design a filter!

Thanks everyone for all your replies and help

 

[Orson Cart]

You cannot use the IR2110 like this except for the lowest mosfet and possibly the one above it. This is because there is no guaranteed return path for the current charging the bootstrap capacitors (all mosfets below the one of interest would have to be on for a finite time every so often to guarantee this). Unless your controller manages the mosfet on times to guarantee bootstrap cap charging then you wil have to use properly isolated supplies to each mosfet source to run the isolated section (i.e. the top half) of each IR2110, you would need an isolated gate drive signal also if you wanted to use the bottom half of the IR2110's.
This problem has been discussed and solved in another thread on this site.