I'm currently making a pure sine inverter using a MOSFET H bridge with following specs.
Vin=360VDC
Vout=230VAC at 50Hz
Output Power=750W
Switching frequency=16kHz
I use Sine modulated PWM(SPWM) as shown below.
At this stage I'm still operating in 100VDC.Earlier I had problems with voltage spikes appearing in the DC bus line which was solved by moving C11 & C12 closer to the H bridge in the PCB layout.when i connect a resistive load directly to the bridge, the waveform of Q2 are almost perfect as shown below with no spikes when Q2 is off and Q4 is switching as in the previous question.
Vgs:cyan Vdsurple Id:Green
However when I connect the LC filter, a ringing appear in Vds.
What is the reason for this?
How can i minimized or avoid this ringing?
How this affects the MOSFETS?
Thanks in advance...
Vin=360VDC
Vout=230VAC at 50Hz
Output Power=750W
Switching frequency=16kHz
I use Sine modulated PWM(SPWM) as shown below.
At this stage I'm still operating in 100VDC.Earlier I had problems with voltage spikes appearing in the DC bus line which was solved by moving C11 & C12 closer to the H bridge in the PCB layout.when i connect a resistive load directly to the bridge, the waveform of Q2 are almost perfect as shown below with no spikes when Q2 is off and Q4 is switching as in the previous question.
Vgs:cyan Vdsurple Id:Green
However when I connect the LC filter, a ringing appear in Vds.
What is the reason for this?
How can i minimized or avoid this ringing?
How this affects the MOSFETS?
Thanks in advance...