Comparative Study of Three-Phase PMSM Controls with Two Current Sensors

At least two phase current sensors are needed to achieve high-performance control in a three-phase permanent magnet synchronous machine (PMSM) drive system. Kirchhoff's equation is commonly used to determine the third-phase current of the motor when designing PMSM control with two current sensors. Recently, the observer-based current reconstruction methods have been proposed for PMSM control with only one or two current sensors. In this paper, comparative studies are conducted for these two current sensor-based control schemes with Kirchhoff's equation and the current observer. In addition, a hybrid two-current sensor control method is introduced by combining these two approaches to achieve improved control performance. Comprehensive simulation and experimental tests are conducted to compare the PMSM control performance under these two different current sensor control schemes. Validation tests are also conducted against the healthy control with three sensors in two different PMSMS.