FPGA permanent magnet synchronous motor floating-point models with variable-DQ and spatial harmonic Finite-Element Analysis solvers

Abstract

This paper explains the FPGA implementation of a Permanent Magnet Synchronous Motor (PMSM) model using the latest JMAG-RT Finite-Element-Analysis software's real-time models: variable-DQ and Spatial Harmonic. In the variable-DQ (VDQ) model, the DQ inductances are varied according to the saturation level and a sinusoidal back-EMF is assumed. In the Spatial Harmonic (SH) model, the instantaneous magnetisation state is used to integrate the model; differential inductance and nonsinusoidal back-EMF are considered for all possible points of operation, resulting in improved precision, especially in transient states. The SH model also includes torque and current harmonics contents induced by machine slots and back-EMF spatial configurations. Both VDQ and SH models are implemented in a ML605 FPGA board running in the RT-LAB real-time simulation environment.