Unexpected behavior resulting from the Three-Phase-Fault block in my simulated circuit (Simulink)

Hi all,

I am simulating a circuit with a 3-phase fault inserted as shown here:

My goal is to simulate the fault at different locations by varying the length of the Distributed Parameters Line blocks many many times, and then collect the 3-phase voltage + current data for training a deep neural network for fault localization. Thus, I used an external control signal to somewhat randomly switch on and off the three-phase-fault block as shown here:

Where SysModel is the one I just showed earlier.

However, the weird thing happens. The external control signal to the 3-phase-fault occurs at around 0.01 second (determined by the pulse generator and delay), and lasts for 0.01 seconds. But the resulting 3-phase voltage and currents in the Time Scope look like this:

this does not make sense because:

1. There is no transient resposne in the currents at all
2. The transient response in the voltages should die out shortly after 0.02, but somehow it automatically turns up again toward the end of the simulation.

Here is the time scope for the external control signal that's going into the 3-phase-fault block (From "Composite Signal 1" in the previous screenshot):

In addition, I am using the following settings for the Distributed Parameters Line blocks:

I'd greatly appreciate any help!

[Gautam]

Hello, Randy

The settings for the distributed parameters look fine. I am unsure as to why the voltage and the current plots look like the way they do. Would it be possible for you to attach your model here so that I can reproduce the behaviour and investigate it further?