Real Time Motor Model for HIL Testing using MATLAB

Motor modeling and motor simulation help you perform tasks ranging from system-level performance analysis to detailed electric motor design. Each task requires different physical effects to be captured in the motor model and motor simulation. Motor drive designers may need to import finite element analysis (FEA) data to optimize drive design parameters while minimizing losses. System engineers often rely on more abstract motor modeling that balances mechanical and electrical power to accelerate motor simulation and analyze system-level performance of a motor drive.

Simulink® and Simscape™ support multiple fidelity levels for motor modeling and motor simulation:

System design:

• No pulse-width modulation (PWM) or power electronic switching
• No mechanical or electrical dynamics
• Energy-based, steady-state equivalent and efficiency map modeling

Control design:

• Ideal switching
• Lumped-parameter modeling
• Linear torque-current relationship

Motor drive design:

• Non-ideal switching – physics-based modeling of power semiconductors
• Saturation – nonlinear dependence on current and/or rotor angle
• Spatial harmonics – including torque ripple caused by cogging and harmonics in the flux linkage

For rapid motor simulation, you can integrate tabulated loss information into a system design level motor model and check the behavior of your design as part of a larger system, while still accurately predicting overall system efficiency. You can develop a proof-of-concept electric drive control strategy for a hybrid electric vehicle using the control design fidelity level for permanent magnet synchronous motor modeling. You can ensure realistic motor simulation behavior by estimating parameter values based on measured data. To account for magnetic saturation or parameter variations under different load levels, you can incorporate FEA data that describes a nonlinear flux-current relationship in your motor model using the motor drive design fidelity level. The highest-fidelity motor simulation can be achieved using additional FEA data on spatial harmonics, to facilitate the development of torque ripple mitigation algorithms and optimize drive design.

This presentation demonstrates this workflow through a case study based on a permanent-magnet synchronous machine. The workflow takes into account:

Modeling motor dynamics required for HIL testing
Deploying the motor model to a HIL system
Testing an embedded motor controller with the HIL system"