Antor
Member level 2
Hello,
I'm trying to build a 3phase-3phase direct converter (Explains my schematics). I'm testing IGBT stage with DC source. Circuit is now just triggering IGBT named SAAF.
Cutting to the chase, I'm triggering only 1 IGBT and chopping a DC for now. I'm sure there will be negative undershoot if I trigger SAAR negative path IGBT too.
There are 3 problems;
1- Overshoot
2- Very bad transient
3- A weird slope after turn-on.
Here is main schematic and its's chield
These are the PCB with top and bottom layers
Signal triggering the IGBT driver (HCPL3140) is generated by signal generator. 5V %50 duty cycle @1KHz
Load is a rheostat (around 10ohms, may varry)
Yellow : Output of the IGBT, Blue : Signal triggering IGBT (HCPL3140 output)
DC source of the IGBT 1A/24.2V, Output have an overshoot and a weird slope during on cycle. PWM signal is not in a good condition also.
DC source of the IGBT 1.24A/30V, Output have an overshoot and a weird slope during on cycle. PWM signal slightly better.
DC source of the IGBT 1.33A/31.7V, Output have an overshoot and the weird slope is gone.
Close shots of overshoot and transient state of turn off
Workspace
How can I condition the output ?
I'm trying to build a 3phase-3phase direct converter (Explains my schematics). I'm testing IGBT stage with DC source. Circuit is now just triggering IGBT named SAAF.
Cutting to the chase, I'm triggering only 1 IGBT and chopping a DC for now. I'm sure there will be negative undershoot if I trigger SAAR negative path IGBT too.
There are 3 problems;
1- Overshoot
2- Very bad transient
3- A weird slope after turn-on.
Here is main schematic and its's chield
These are the PCB with top and bottom layers
Signal triggering the IGBT driver (HCPL3140) is generated by signal generator. 5V %50 duty cycle @1KHz
Load is a rheostat (around 10ohms, may varry)
Yellow : Output of the IGBT, Blue : Signal triggering IGBT (HCPL3140 output)
DC source of the IGBT 1A/24.2V, Output have an overshoot and a weird slope during on cycle. PWM signal is not in a good condition also.
DC source of the IGBT 1.24A/30V, Output have an overshoot and a weird slope during on cycle. PWM signal slightly better.
DC source of the IGBT 1.33A/31.7V, Output have an overshoot and the weird slope is gone.
Close shots of overshoot and transient state of turn off
Workspace
How can I condition the output ?