Adaptive full-order observer analysis and design for full-range sensorless interior permanent magnet synchronous motor drives

Abstract

This Thesis presents contributions to the study, development, analysis and design of adaptive observers applied to the estimation of rotor position and speed of interior permanent magnet synchronous motors (IPMSM). The position estimation techniques for the IPMSM are divided in low and high speed methods. First, the adaptive fullorder observer analysed and designed for high speed sensorless control. A cascade design method is presented for high performance estimation and robustness improvement under speed estimation error. An analysis of parameter variation effects on position and speed estimation is presented. Then, the adaptive full-order observer is modified for fullrange IPMSM sensorless control. A high-frequency injection technique is used in order to guarantee position observability. The cascade design approach is adopted for the adaptive observer gains design. Experimental results are presented in order to validate the proposed adaptive observer design method.