How can I create a high-fidelity model of PMSM drive systems using Simscape?

To verify the initial position estimator, I have constructed a model of a PMSM drive system using Simscape. The model consists of various components including a power source, uncontrolled rectifier, DC bus, and inverter (sample frequency 10MHz, fixed step solver). The topology of the model is as follows:

I think it is a very simple topology; however, I am unable to achieve the desired dynamic response. For example, if I feed the IPM with a gate signal (1 0 0 0 1 1), which represents vector V1 in SVPWM, I cannot achieve the expected current response, and the DC-bus current could easily exceed thousands of amps. So, I would like to know if it is possible to build a model that replicates the circuit diagram and produces a similar (or almost similar) response. If not, are there any guidelines for modeling high fidelity drive system models? Thank you!

Answer 1

[Kothuri]

Hi,

I understand that you want to model a PMSM drive but it not working as expected. Modelling a high-fidelity PMSM drive system in Simscape to achieve a realistic dynamic response, especially for verifying components like an initial position estimator, requires careful attention to several aspects of the model.

• Ensure that all model parameters (e.g., motor parameters, resistance, inductance, etc.) are accurately represented based on the real system or the manufacturer's datasheet. And try to use stiff solvers as they can handle the system efficiently.
• Verify the accuracy and timing of the gate signals. Incorrect timing can lead to unexpected current paths and potentially high currents.

You can refer the below MATLAB example of Simulation of a PMSM Drive

https://www.mathworks.com/help/sps/ug/three-phase-pmsm-drive.html

You can refer the below links for MATLAB File Exchange having the models of SVPWM based control of PMSM

https://www.mathworks.com/matlabcentral/fileexchange/42938-svpwm-based-open-loop-speed-control-of-pmsm-with-multi-level-inverter-by-v-by-f-method

https://www.mathworks.com/matlabcentral/fileexchange/63837-vector-control-of-permanent-magnet-synchronous-motor-pmsm