Simpowers plus simmechanics

Question

I need to combine in MATLAB model of machine in SimMechanics with blocks of SimPowerSystems: asynchronous machine. I googled it but didn't find any relevant article. In my work I should consider impact of bearings like reaction forces and etc. Is this possible?

Answer 1

It depends which release of SimPowerSystems/SimMechanics you are using.

In the older versions, the way to connect a mechanical model in SimMechanics to an electrical model in SimPowerSystems was via the speed input of the electrical machine blocks in SimPowerSystems. These are Simulink signals which would come from the corresponding sensor blocks in the mechanical part of the model. There would then be a feedback where torque output from the electrical model would be fed back as an input into a force/torque source block into the SimMechanics model. When paramterising the model, you have to be careful not to account for the rotor inertia twice. Typically, the inertia is already accounted for in the mechanical part, so you would set it to zero in the electrical machine block.

In the newer versions, both SimMechanics and SimPowerSystems use Simscape as the underlying foundation, so I believe you can have acausal mechanical connection between electrical and mechanical block, without having to worry about feeding speed or torque signals back and forth. However, I don't have so much experience of the newer versions, so I am less sure about that.

Have a look at some of the webinars to get some ideas. There are also some good examples to use as a starting point in the File Exchange.