How can i reverse the positive/negtive sign of the torque of a synchronous machine (salient pole)?

I am simulationg an electricaly-coupled generator and motor problem.

A synchronous generator is driven by the fixed torque i.e the turbine.

A motor is driven by the electricity generated by the generator.

The generator is accelerated as is expected, but the speed of the motor decreases to zero.

The torque of the motor is in the direction of decreasing the speed.

Can anybody tell me how to reverse the positive/begative sign of the torque of a synchronous machine(salient pole)?

Answer 1

[Joel Van Sickel]

Hello Shimmei,

there are mutliple issues that could be causing this and more information is needed to help. Generically, you first want to make sure that your genrator is generating the correct amount of power when it is up to speed. You can test this by replacing the motor with a resistive load and making sure the power draw makes sense. If this is working, the next step is to make sure that your motor is working. This is where how you are starting the motor will matter. Are you starting it synchronously or asynchronously? I would assume asynchronously but cannot be sure. If you are applying external torque to your motor, I would stop that for now, and just see if you can spin it at no load. You should apply your field current at the appropriate time based on how you are trying to start it.

Regards,

Joel