Enhanced rotor field‐oriented control of multiphase induction machines based on symmetrical components theory

Abstract

Fault-tolerant capability greatly promoted the application of multiphase machines on safety-critical occasions, and fault-tolerant control strategies are required to suppress the torque ripples. Based on the generalised symmetrical components (SCs) theory, a general expression of the independent SCs is derived during the fault-tolerant operation of symmetrical multiphase machines in this study, and coefficients of the four basic rotating components in the general expressions are calculated for specific open-circuit conditions. Then the bidirectional rotating proportional-integral controllers are designed to control all the rotating components in each SC. Considering control loops for all the independent SCs, an enhanced rotor fieldoriented control fault-tolerant strategy is proposed for symmetrical multiphase induction machines (IMs) with any phase number m. Furthermore, additional rotating current controllers in the first SC control loop are added to reduce the low-order current harmonics during the fault-tolerant operation. Experimental evaluations in terms of the transient, dynamic and harmonic performances on both five-phase and nine-phase IM drive platforms are provided to verify the effectiveness of the proposed fault-tolerant strategy.

Field-Oriented Control of Five-Phase Induction Motor Fed From Space Vector Modulated Matrix Converter

“…() (17) From ( 14)-( 17), one can derive ( 18) and (19). By putting ( 18)-( 19) in ( 13) and the resulting set of equations can be written as (22), which is the description of the voltage subsystem in the induction machine.…”

Torque Ripple Minimization of a Five-Phase Induction Motor Under Open-Phase Faults Using Symmetrical Components

“…SC theory was first proposed in 1918 to analyze the steady-state performance under asymmetrical power supply [32], and it has been used widely in the multiphase drive applications [21,23,[33][34][35][36][37]. Because of the MMF coupling for the multiphase IM under open-phase faults, the torque cannot be decoupled using traditional multiphase Park transformation.…”

“…In addition, based on the features of SCs under fault conditions, a robust fault detection method was proposed for a five-phase motor in [35]. In order to suppress low frequency current harmonics and improve the stability of the current controller, the positive and negative sequence currents related to all SCs are controlled in the rotating frame separately [36][37].…”

Novel space vector PWM technology with lower common‐mode voltage for dual three‐phase PMSM

“…Multiphase machine drives have gained an increasing attention in recent years due to many advantages such as lower current stress of individual semiconductor switches, higher system-level reliability, lower torque pulsations and less demanding DC-link voltage requirement [1][2][3][4]. Among different multiphase motor drive systems, one of the most attractive and widely-researched topologies is the dual three-phase machine drive, as shown in Fig.…”