Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.722804
Title: Open winding permanent magnet synchronous machine drives with particular reference to zero sequence
Author: Zhan, Hanlin
ISNI:       0000 0004 6421 8375
Awarding Body: University of Sheffield
Current Institution: University of Sheffield
Date of Award: 2017
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
Permanent magnet synchronous machines have drawn much research attention in recent years due to their superiorities on torque density, efficiency, and power factor etc. Meanwhile, the open winding topology can enable the machines to obtain higher DC bus voltage utilization ratio, better fault tolerant capability and higher torque output. Hence, the research on open winding permanent magnet synchronous machines has increased recently. In this thesis, the open winding permanent magnet synchronous machine drives are studied with particular reference to zero sequence. Firstly, the open winding permanent magnet synchronous machine drives having common DC bus suffer from the zero sequence circulating current issue, which increases the losses and torque ripples. The mechanism analysis of the zero sequence circulating current is therefore presented. The integrated model is established and the influences of the cross coupling voltages in zero sequence and the parasitic effects in inverter nonlinearity are firstly identified. Moreover, two suppression strategies are subsequently proposed, which include the model based and non-model based methods. The non-model based method is constructed on the frequency adaptive proportional resonant controller and has fast dynamic. The nonmodel based method is based on the extremum seeking algorithm and has better generality for different machines. Secondly, the zero sequence is also utilized to improve the torque performance of the open winding permanent magnet synchronous machine. The zero sequence current injection is adopted to enhance the average torque component of the open winding permanent magnet synchronous machine where the zero sequence back electromotive force is used. Also, the shifted zero sequence current injection can be used for torque ripple reduction. The proposed torque ripple reduction method reduces the bandwidth requirement of the current controller from 6 times of the fundamental frequency to 3 times of it. Thirdly, the zero sequence characteristics are developed for the sensorless control as well. Two zero sequence back electro-motive force based methods have been proposed, which have higher robustness and non-parametric advantages, respectively. The zero sequence saliency information together with the zero sequence high frequency voltage injection sensorless method is also proposed for the zero and low speed operating region that is not applicable for the back electro-motive force based methods. Finally, the proposed analyses and methods are all validated via the laboratory open winding permanent magnet synchronous machine drive systems and the 2 dimensional finite element analyses.
Supervisor: Zhu, Zi-qiang ; Odavic, Milijana Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.722804  DOI: Not available
Share: