Novel MTPA control strategy for IPMSM based on multiple virtual signals injection

Abstract

Virtual signal injection-based maximum torque per ampere (MTPA) control method is widely employed for increasing the efficiency of the interior permanent magnet synchronous machine (IPMSM) due to its simple implementation. However, the conventional method utilises the filters to extract MTPA indicator, which limits the dynamic tracking performance of MTPA operating point. In order to improve the dynamic tracking performance, a novel strategy to use multiple virtual signals injection is proposed in this study. With the proposed method, four small virtual high-frequency signals are constructed to extract the MTPA indicator information. The MTPA indicator can be calculated directly by solving multiple acquired equations instead of any filters. Due to the absence of filters which are essential in the conventional method, this proposed method shows good dynamic response. The feasibility of the proposed method is verified under various operating conditions with a 1.2'.kW IPMSM drive system.