Position-Sensorless MTPA Control of IPMSM Based on High-Frequency Signal Injection

This paper proposes a position sensorless MTPA tracking method for IPMSM under the condition that only the nominal parameters are given. This is a very practical issue because achieving design data or preliminary tests for extracting electrical characteristics are difficult in many industrial drive applications. For this target, an algorithm for MTPA operation, that is applicable in the estimated d-q reference frame, is proposed. It adjusts the operating point into the MTPA point, automatically. Theoretical analyses and experimental results verify that tracking of MTPA trajectory is possible through the proposed method even in the sensorless operation with an uncharacterized motor.