Shorted power switch in a Three phase inverter

Thread Starter

Vlad Vsky

Joined May 15, 2017
Hi everyone,

I noticed recently that some researchers in Electrical engineering are trying to detect and localize a faulty power switch in a three phase inverter. However, in the case of a short circuit fault (of a power switch), the current in the DC link increases enormously in a very short time ! so, practically, there is no time neither to detect nor to localize, .. the protection will just shut down the whole thing.

What are your opinions about this ?
see the picture bellow.



Joined Feb 20, 2016
Disconnect it from the power and the motor first. Allow time for the capacitors to discharge (measure for residual voltage and wait until it is zero).
Measure each transistor with a multimeter looking for shorts.
Also, check the electrolytic capacitors. When they die, other parts suffer too.
That's a start.