Impact of Postfault Flux Adaptation on Six-Phase Induction Motor Drives With Parallel Converters

Abstract

Abstract-The redundancy of multiphase drives provides an inherent fault-tolerant capability that is appreciated in applications with a complicated corrective maintenance or safety-critical requirements. Fault restrictions however force the system to be reconfigured to operate in a smooth and efficient manner. Previous works have been focused on the optimization of current waveforms to generate an undisturbed operation but still maintaining the pre-fault rated flux settings. This work shows that efficient controllers can improve the post-fault performance in six-phase induction machines supplied by parallelconnected converters if offline optimization is used to obtain a variable reference flux. Theoretical and experimental results confirm that the proposed flux adaptation method provides higher torque/power capability, lower degree of imbalance in the current sharing between windings and efficiency improvement.

Unified Fault-tolerant Control Strategy with Torque Ripple Compensation for Five-phase Permanent Magnet Synchronous Motor Based on Normal Decoupling

“…Research on multiphase motors aims at improving the reliability, fault diagnosis, and fault-tolerant operation of specific targets. Keeping these applications in mind, several recent works have focused on the development of high-performance, fault-tolerant control schemes for induction machines (IMs) and permanent magnet synchronous machines (PMSMs) [4][5][6][7]. The diagnoses focus on rapidity and accuracy [8,9], and adoption of effective isolation measures, such that a corresponding fault-tolerant control scheme can be adopted.…”

A Simple Braking Method for Six-Phase Induction Motor Drives With Unidirectional Power Flow in the Base-Speed Region

“…Interestingly enough, the strategy during braking is to make the motor as inefficient as possible within physical limits. While the flux is typically reduced in the base speed region to improve efficiency [10][11], the flux should be increased during braking to worsen the efficiency and thus decelerate the motor faster. However, high flux values over-magnetize the machine leading to magnetic noise in the base speed region and overvoltages in the fieldweakening region [12].…”

An Open-phase Fault Detection Method for Six-phase Induction Motor Drives

“…The fault management in a drive can be classified in three stages: fault detection FD [13][14][15][16][17], fault isolation FI [18][19] and implementation of a fault tolerant control (FTC) [20][21][22][23][24][25]. The implementation of these three stages in the system is necessary to ensure a suitable operation and to protect the system in post-fault situation.…”