How do I connect three phase block in simulink?

Hello everyone, I am trying to run a simulation assessing the functionality of my relay trip logic intended to protect a three-phase transformer. Unfortunately when I connect the three-phase fault block it only adds 2 A to the total current which is too low for my relays to work but also completely unrealistic for a three phase fault which should be in the range of kA. Below I uploaded a screenshot of the model as well as a scope displaying the load current (three phases,RMS values). The exact same logic works well for a fault at the transformer primary winding,as it picks up the fault current in the range of kA in that case. Thanks in advance for any answers.

Answer 1

[Tushar]

Hi Georgios,

Please refer to the following documentation. I hope it may help:

Three-Phase Fault

[Georgios Karvounakis]

Hi Tushar,

Thanks for the reply.I have studied the block in depth, unfortunately it does not work as intended on my model.

Answer 2

[Tushar]

Hi Georgios,

As you mentioned, "The exact same logic works well for a fault at the transformer primary winding,as it picks up the fault current in the range of kA in that case", verify that the three-phase fault block is connected correctly to the rest of the system. Make sure it is properly connected to the primary winding of the transformer and that the fault block's output is connected to the load current measurement or relay logic.

Ensure that the fault is being triggered properly in your simulation. Check if there are any conditions or triggers required for the fault block to activate. Verify that these conditions are met during the simulation.