Hello Everyone.
First of all please put the thread in the correct place, I didn't found a better forum to ask it.
I'm designing a high frequency inverter to drive high voltage a piezo emitter.
The power is driven by on two UCC27211. The voltage of the bridge is 24Vdc and the load right now is a transformer (primary - 65uH - 1.27Ohm), in the secundary I have a piezo emitter.
The mosfets used on the bridge are 4 IRFP4410z with 4820 pF of Input Capacitance.
The signal in the output is 20kHz to 60kHz and to recreate the sinusoidal I use a 10x PWM signal, so the maximum frequency in the driver and mosfets is 600kHz.
The schematic is attached, during my tests I made different changes, removed and added different components what I have now is more or less the attached schematic. The colored circles are the colors of the signals of the screenshots from the oscilloscope.
The most strange for me is the signal generated in the gate of the high-side mosfet, because according to the scope it's the same signal than the source of the mosfet (middle point of the bridge). The output signal of the low side mosfet is good enough, but the rest of the signals are not the best. I also can not figure out why I have 115V in the high side gate if the voltage from the supply is only 24, according to the datasheet should be around 36V (24V + 12Vgs).
Can someone helps me?
Thanks a LOT.