Analysis and Optimization of Current Dynamic Control in Induction Motor Field-Weakening Region

The maximum-torque-output (MTO) trajectory can achieve optimal current distribution for induction motor (IM) field-weakening (FW) control. To provide the dynamic model for MTO, this letter proposes quantitative analysis of the current dynamic character in FW control. As the current vector moves along MTO trajectory, the current changing rate and voltage margin requirement are calculated to study the dynamic control objective and the realization condition of FW control. According to the summarized changing law of voltage margin requirement, the d-axis voltage margin priority approach is applied to the IM FW system for current dynamic optimization. The effectiveness of the studied method is verified through comparison experiments on an advanced RISC machine (ARM)-based 3.7-kW IM platform.