Evaluation of Single Current Regulator Based Field Weakening Strategy For PMSM Drives and Experimental Validation using HIL

Abstract

Permanent Magnet Synchronous Motors (PMSM) are widely used in traction purposes. It has the advantage of high efficiency, robustness, and good control characteristics. For the traction purpose, field weakening control is required to obtain wide speed operation. When the voltage reaches its maximum value, speed extension is possible by weakening the air gap flux. Direct weakening of air gap flux is not possible while it is possible by applying a demagnetising stator current. The conventional methods of flux weakening strategies are feed-forward flux weakening strategy and feed-back fluxweakening strategy. Feed-forward method depends upon the motor parameters an this leads to the instability of the system. The utilization of two current PI regulators leads to the saturation problems also. A Single Current Regulator (SCR) based flux weakening strategy is used to remove the saturation problem. In this strategy, dc bus voltage is fully utilized and provides better dynamic response. The simulation of the presented control is done by using MATLAB-Simulink and experimental evaluation is done using Typhoon HIL-402 in RBS mode.