Power electronics converters for open-winding motor drives
Prof. Dong Jiang, Huazhong University of Science and Technology
A. Prof. Zicheng LIU, Huazhong University of Science and Technology
Dr. An LI, Huazhong University of Science and Technology

Abstract：
This tutorial gives an introduction on the recent technologies in the power electronics converters for open-winding motor drive.
Compared with traditional three-phase AC motors with Y-connected windings, the open-winding structure has many potential advantages such as wide speed operation range, fast dynamic response, more control freedoms, and strong fault-tolerant capability. Therefore, the topology and control of power electronic converter for open-winding motor drive has important theoretical research value and engineering practice significance.
Three major types of open-winding motor are used as examples to study: reluctance motor, multiphase open-winding AC machine and active magnetic bearings (AMB). They share the similarity of open-winding structure, but are for different performance and targets. Systematic study of these kinds of open-winding motor drive has been done in recent years.
In this tutorial, the optimization progress of the open-winding reluctance motor drive is introduced step by step. By optimizing the zero-axis DC current flow path, the capacity and number of power devices in the open-winding H-bridge topology are gradually reduced, and several novel open-winding topologies are proposed.
Further, several novel technologies of multiphase open-winding AC motor drive are introduced. A novel kind of multiphase open-winding motor drive: series-winding motor drive (SWMD) is introduced, which is able to be applied in normal AC motor and increase the voltage utilization range significantly. Open-winding motor with floating capacitor is introduced for multiphase AC motor also, to improve the power factor and speed range. Moreover, a Re-configurable open-winding multiphase drive is introduced, which is able to reconfigured the circuit for the faulty phase and maximize the torque output capability of the post-fault drive system.
Active magnetic bearing is a key technology for high speed rotational machinery in many advanced applications for rotor suspension. Open-winding power electronics controller is one of the most important part in the AMB system.This presentation introduces progress in the power electronics controller for AMB system. One progress is the topologies for multi-axis AMB, to reduce the power electronics devices and power losses by device sharing principle. The other progress is the fault-tolerant AMB drive, to re-construct the levitation force after failure of power electronics device and improve the reliability.
This tutorial gives a road map for research and application of power electronics converters in the area of open-winding motor drive. The speakers have published more than 30 IEEE papers and 30 granted patents in this field and the related work has been awarded with “Gold Medal with Congratulations of the Jury” in 47th International Exhibition of Inventions of Geneva.
OUTLINE OF TUTORIAL
1.Introduction of open-winding motor drives
1.1Electrical machines with open-winding requirement 
1.2Power electronics converters
2Topology and control for open-winding reluctance motor drive
2.1Principle of DC-RM
2.2Basic topology for DC-RM drives: H-bridge converter
2.3Asymmetric converter: optimization of device rating
2.4Three-phase four-leg converter: utilization of common DC bias current
2.5Three-phase series-winding converter
2.6Summary
3Multiphase open-winding motor drives
3.1Introduction 
3.2Series-winding multiphase drive
3.3Open-winding multiphase drive with floating capacitors
3.4Re-configurable open-winding multiphase drive
3.5Summary
4Open-winding converters for active magnetic bearings
4.1Active magnetic bearing drives: progress in the past
4.2Three-half-bridge converter and its control for AMB drive
4.3Fault-tolerant AMB drive
4.4Shared-phase-leg converter: multi-axis optimization
4.5Summary
5Conclusions

Biography：

Dong Jiang (Senior Member, IEEE) received the B.S. and M.S. degrees in electrical engineering from Tsinghua University, Beijing, China, in 2005 and 2007, respectively. He received the Ph.D. degree in power electronics and motor drives in 2011 in the University of Tennessee, Knoxville, TN, USA. He was with the United Technologies Research Center (UTRC), East Hartford, CT, USA, as a Senior Research Scientist/Engineer, from January 2012 to July 2015. He has been with the Huazhong University of Science and Technology (HUST), Wuhan, China, as a Professor, since July 2015. His main research interests include power electronics and motor drives, with more than 100 published IEEE journal and conference papers in this area. Dr. Jiang was the recipient of several best paper awards in IEEE conferences. He is an Associate Editor for the IEEE Transactions on Industry Applications, the chair of IEEE Power Electronics Society Wuhan Chapter and Vice Chair of IEEE PELS China.
 

Zicheng Liu (M’18) was born in Shandong, China, in 1989. He received the B.S. degree in Hydropower Engineering from Huazhong University of Science and Technology (HUST), Wuhan, China, in 2011, and the Ph.D. degree in Electrical Engineering from Tsinghua University, Beijing, China, in 2016. During Otc. 2014 to Mar. 2015, he was a Visiting Student at Purdue University, West Lafayette, IN, USA. During Jun. 2016 to Sep. 2018, he was a postdoc researcher at Beijing Jiaotong University, Beijing, China. He is currently an associate professor at HUST. His research interests include multiphase motor control systems and transportation electrification.
 

An Li (S’17) was born in Wuhan, China, in 1996. He received his B.Eng. degree and Ph.D. degree both in electrical engineering from School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China, in 2017 and 2022, respectively. His research interests include motor drive, power electronic converter, reluctance machine and multiphase machine.