Switching Frequency Signal-Injection Sensorless Control in Dual Three-Phase PMSM Robust to Nonideal Characteristics of Inverter System
Yoon-Ro Lee, Seung‐Ki Sul
Abstract
This paper mainly describes a signal-injection sensorless control (SISC) method whose injection frequency is the same as the inverter's switching frequency. It has been known that the switching frequency SISC is vulnerable to non-ideal characteristics of the inverter system. In this paper, the current measurement noise and the deadtime effects are considered as the non-ideal factors. The two factors are identified with some analyses, and a hint for the mitigation is found in the dual three-phase permanent magnet synchronous motor (DPMSM) drive system. An asymmetric SISC method is proposed based on the hint; it implements the SISC differently in the two individual three-phase windings of the DPMSM. The method can conspicuously reduce the position estimation error due to the non-ideal factors of the inverter system. During the descriptions, the mutual coupling inductance between the two three-phase windings is considered by using finite element analysis (FEA). The proposed method is verified in the experimental set-up with a 1.7 kW DPMSM.