Title: Robust flux observer and robust block controller design for interior permanent magnet synchronous motor under demagnetisation fault
Authors: Sajjad Shoja-Majidabad; Yashar Zafari
Addresses: Electrical Engineering Department, University of Bonab, East Azerbaijan, Bonab, Iran ' Electrical Engineering Department, Azad University of Malekan, East Azerbaijan, Malekan, Iran
Abstract: This paper deals with rotor flux-linkage estimation in interior permanent magnet synchronous motor. In most applications, the rotor flux is considered as a known constant. However, sharp transients, high loads and high temperatures may cause demagnetisation which has dominant impact on the motor performance. As a result, estimating the rotor flux-linkage can be helpful to detect and manage demagnetisation faults. To estimate the rotor flux-linkage, a novel integral terminal sliding mode observer is proposed. The observer uses stator currents as state variables which can tolerate well against the motor uncertainties. To keep the motor performance during the demagnetisation fault, a sliding mode block control strategy is proposed for the interior permanent magnet synchronous motor for a first time. The suggested robust controller is composed of a speed control loop and two stator current control loops. Comprehensive simulations are carried out to show the effectiveness of the proposed observer and controllers.
Keywords: interior permanent magnet synchronous motor; integral terminal sliding mode observer; sliding mode block control; maximum torque per ampere; demagnetisation fault.
International Journal of Modelling, Identification and Control, 2018 Vol.30 No.3, pp.206 - 218
Received: 11 Jan 2017
Accepted: 03 Sep 2017
Published online: 17 Sep 2018 *