Current derating in fault-tolerant multiphase induction motor drives

• Published in: Power Electronic Converters and Induction Motor Drives
• Main Author: Che H.S.; Tousizadeh M.; Munim W.N.W.A.; Rahim N.A.
• Format: Book chapter
• Language: English
• Published: Nova Science Publishers, Inc. 2022
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85143953457&partnerID=40&md5=1220b6ffdcb2a42bd602ec08f5613d71

In terms of reliability, multiphase drives are often considered to be superior to conventional three-phase drives due to their higher degrees of freedom. With the keen interest from both academia and industry, substantial progress has been observed in the development of fault-tolerant multiphase drives over the past two decades. When operating under open-circuit faults, the phase currents in a fault-tolerant multiphase machine will need to be increased above their pre-fault levels to maintain the same torque-speed performance. As a result, special care needs to be taken in understanding the post-fault current limits and control technique to ensure the safe operation of the machine. This chapter discusses the concept of current limits for a multiphase induction machine, based on a symmetrical six-phase machine, to demonstrate how the machine needs to be derated under different open phase faults. Furthermore, the impact of flux and torque current partitioning is discussed, where it is shown that the derating of current should be distributed to the flux and torque component correctly to maximize the post-fault performance of a multiphase drive. © 2022 by Nova Science Publishers, Inc. All rights reserved.