High Response Torque Control of IPMSM Using State Feedback Control Based on n-t Coodinate System

Abstract

This paper proposes a torque control method for interior permanent magnet synchronous motors (IPMSMs). The proposed method uses state feedback control based on a new n-t coordinate system and controls the voltage amplitude and phase based on the coordinate system. The t-axis is a tangent line of the constant voltage ellipse, and the n-axis is a normal line of the ellipse. The n-axis current is utilized to place the poles of the transfer function at the desired position and reduce the mutual coupling between the voltage amplitude controller and phase controller. The proposed method realizes a high torque response even under parameter variation for the linear range and over-modulation range of the inverter, including a six-step mode. The effectiveness of the proposed method was verified by simulation and experimental results.