Improved rotor position estimation by signal injection in brushless AC motors, accounting for cross-coupling magnetic saturation

The paper presents an improved signal injection- based sensorless control method for permanent magnet brushless AC (BLAC) motors, accounting for the influence of cross-coupling magnetic saturation between the d- and q-axes. The d- and q-axis incremental self-inductances, the incremental mutual-inductance between the (d-axis and q-axis, and the cross-coupling factor are determined by finite element analysis. A method is also proposed for measuring the cross-coupling factor which can be used directly in the sensorless control scheme. Both measurements and predictions show that a significant improvement in the accuracy of the rotor position estimation can be achieved under both dynamic and steady-state operation, compared with that which is obtained with the conventional signal injection method

Improved rotor-position estimation by signal injection in brushless AC motors, accounting for cross-coupling magnetic saturation

This paper presents an improved signal-injection- based sensorless-control method for permanent-magnet brushless ac (BLAC) motors, accounting for the influence of cross-coupling magnetic saturation between the d- and q-axes. The d- and q-axis incremental self-inductances, the incremental mutual inductance between the d-axis and q-axis, and the cross-coupling factor are determined by finite-element analysis. An experimental method is proposed for measuring the cross-coupling factor which can be used directly in the sensorless-control scheme. Both measurements and predictions show that a significant improvement in the accu- racy of the rotor-position estimation can be achieved under both dynamic and steady-state operation compared with that which is obtained with the conventional signal-injection method

Sensorless drives for permanent magnet synchronous motors

Ph.DDOCTOR OF PHILOSOPH

Estudo e comparação de diferentes métodos de controlo de motores síncronos com ímanes permanentes

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores - Major Automação. Faculdade de Engenharia. Universidade do Porto. 200