Position Sensorless Vector Control Method for IPMSM Drives Based on Vector Trajectory of Current Estimation Error

Interior permanent magnet synchronous motors (IPMSMs) position sensorless drives have been widely used in recent years. These drives should be able to handle low-speed operation. Control methods of IPMSM based on current observers generally assume that the position error is sufficiently small. In this paper, the authors have proposed a new position estimation method based on vector trajectory of the current estimation error. This position estimation method consists of two parts. First, the sign of the position error is estimated based on the outer product of the current estimation error and the reference vector. Next, the amplitude of the position error is calculated from the intersection of two circles determined by motor parameters and the current estimation error. The proposed position sensorless method is implemented on a DSP controller, and the effectiveness of the proposed control method is confirmed experimentally. (C) 2016Wiley Periodicals, Inc.