Variable-Parameter Field-Oriented Control for Interior-Permanent Magnet Synchronous Machine Drives

Interior permanent magnet synchronous machines (IPMSMs) are becoming widely considered in many applications, including appliances, manufacturing machinery, medical equipment, military equipment, propulsion systems, servo systems, etc. In IPMSMs, the flux linkage may vary significantly depending on the design and operating conditions, and their accurate modeling and control are essential. Look-up tables (LUTs) may be used to represent the flux-current relationship, which inherits the magnetic-flux saturation and cross-coupling characteristics. This paper presented a variable-parameter (inductance) field-oriented control (FOC) strategy with a feedforward speed loop for IPMSM drives, wherein the LUTs are used to represent the current-flux relationship and update the gains of the PI controllers for better decoupling between the q- and d-axes currents. The simulation studies demonstrate the proposed methodology of the variable-parameter FOC for IPMSMs in the unsaturated and saturated regions and its advantages over the conventional FOC algorithm.