Guru
Joined: 21/06/2018
Location: AustraliaPosts: 1267
| Posted: 03:32pm 01 May 2021 |
Peter, I advise don't rush into a new design just yet & let the waters settle a bit and see what we can collectively agree to and come up with. I think there was/is a trend towards over engineering the inverter at this stage, of course all with the right intentions but there may be other paths to a simpler but more robust design.
For interest why not tack some 4.7R resistors in parallel with the 10 Ohm gate drive resistors on your board - maybe just on one or both of the low side FETs and look to see if the gate bounce issue is improved (less). Afterwards if further inspired also try a ferrite bead on each of the Drains of the low side FETs - just on one side and see if the tendency towards oscillation has gone (obviously on that side....)? I am assuming the FET's are insulated from each other & the heatsink. If this is too hard to achieve don't go to the trouble.