Issues Using Three-Phase Core Coupling in Parallel Inverter Simulation

Question

Hello, I am currently running a parallel operation simulation of two inverters, with a linear resistive load at the output. A three-phase core coupling is added to each inverter (current source on the left side and voltage source on the right side). According to the simulation results, the second inverter’s voltage and current are controlled normally, but the output current of the first inverter cannot be delivered to the load, and its current waveform becomes distorted, although the voltage control is normal. As a result, parallel control cannot be achieved.

If I change the three-phase core coupling configuration to “voltage source on the left side and current source on the right side”, the control performance becomes even worse.

I would like to ask: what is the correct way to use the three-phase core coupling in parallel inverter simulations? Do I need to modify any parameters inside the coupling block? Thank you.

Answer 1

Hi,

Have you checked the following documentation page: (https://www.typhoon-hil.com/documentation/typhoon-hil-software-manual/concepts/coupling_best_spots.html#:~:text=should%20be%20checked.-,Converters%20connected%20in%20parallel,-In%20Figure%2011)

That can give you some ideas.

BR

Answer 2

Hello,

I recommend you 2 ways:
Reviewing the Recommended coupling page in Typhoon Documentationas in the previous answer given. Especially with series or parallel connected inverters.

Second, try to add the snubbers, maybe you only finally need a resistor and not the full one, because without snubbers you can have great distortions than change the results from what was expected.

Hope, this could work.
Kind regards.