Controller design for a sensorless permanent-magnet synchronous drive system

The authors investigate the design of H² and H^∞ controllers for a permanent magnet synchronous motor drive system without using a shaft position sensor, and present a field-weakening control algorithm of the drive system. Robust PI, H² and H^∞ control techniques are applied to the design of servo controllers. A fully digital control system under the vector control framework is constructed for experimentally verifying controller performance. The theoretical development is validated by experimental work. The authors provide a new approach to designing sensorless AC drives using currently available high performance microprocessors