Modelling the synchronous generator block as a voltage source

Hi everyone,

I'm trying to model a power grid using synchronous generators injecting power at different busses. The issue is that the sychronous generator block from the Specialized Power Systems library is essentially a current source so it is not grid-forming. Because of that, when I try to simulate a simple system with just one generator connected to a single load, when the generated power is not equal to the load power, the frequency either ramps up or down with no sign of reaching steady-state. The image "simulink_currentmodel" shows the model I currently have.

Is there any way to convert the synchronous generator from a current source to a voltage source? Adding a voltage source (like shown in the image "simulink_voltagesource", circled in yellow) causes the frequency to reach the nominal voltage in steady-state for all load/generation power combinations. I had expected the droop action to take effect, so that there is a deviation in the steady-state frequency from the nominal for situations where the generated power does not equal the generated load.

[Lawrence Hiquiana]

Were you ever able to figure out this problem? I am having a similar problem and am looking for potential solutions.

Answer 1

[Sabin]

Would be helpful to check Simscape Electrical. There are blocks that will work in grid forming. A good starting point is this MATLAB Central example:

https://mathworks.com/matlabcentral/fileexchange/123870-renewable-energy-integration-design-with-simscape

There is also this similar question on MATLAB Answers:

https://mathworks.com/matlabcentral/answers/1648925-is-there-a-way-to-model-a-synchronous-machine-as-a-voltage-source-instead-of-current-source