Can't Visualize IGBT Overlap in 3-Phase Inverter Simulation (Simulink / Simscape)

I'm working on a simulation of a three-phase inverter using 6 IGBTs in Simulink/Simscape Electrical. My goal is to visualize an overlap (shoot-through) condition — that is, when both the high-side and low-side IGBTs of one inverter leg are ON at the same time, which could cause a short circuit through the DC bus.

Here’s what I’ve done so far:

• I'm using sinusoidal PWM (SPWM) based on 3 sine waves and 1 triangular carrier.
• I set the dead-time to zero in my PWM generation.
• I disabled snubber circuits in all IGBTs.
• I visualized gate signals (Vge) and collector currents (Ic) using scopes.
• Modifying the IGBT parameters (turn-on/turn-off times, internal resistance, etc.)
• Switching between continuous and discrete solvers

But despite everything, I can’t observe any overlap between IGBTs — no shoot-through, no simultaneous conduction.

Answer 1

[Sabin]

In the case of IGBTs, it is possible to switch ON the opposite IGBT while the tail current is still flowing without causing damage. Although a longer dead time can help reduce power loss, a zero dead time is sufficient to prevent destructive shoot-through currents. For this kind of analysis is best to use the N-Channel IGBT block and play with total forward transit time.

A good read about this is: D. W. Berning and A. R. Hefner, "IGBT half-bridge shoot-through characterization for model validation," IAS '96. Conference Record of the 1996 IEEE Industry Applications Conference Thirty-First IAS Annual Meeting, San Diego, CA, USA, 1996, pp. 1491-1499 vol.3, doi: 10.1109/IAS.1996.559265.