Research On Fault Diagnosis And Fault Tolerant Control Of Five-phase Induction Motor

Compared with the traditional three-phase induction motor,the multi-phase motor has the advantages of low voltage supply,low torque ripple and high reliability,and thus,it is widely applied in the field of high-power control.The fault diagnosis of the multi-phase induction motor and the fault-tolerant control technology are also developing rapidly.This paper takes five-phase induction motor as the research object,researches the fault diagnosis and fault-tolerant control of motor.The main works and achievements are as follows:Firstly,based on vector space decoupling,the five dimensional motor variables in natural coordinate system are transformed into different vertical subspaces,and the mathematical model of five-phase induction motor is established.And the model of the motor is built in the MATLAB environment.Secondly,based on the established five-phase induction motor model,a variable frequency speed control system is proposed to realize the speed control of the fivephase induction motor under normal conditions.In order to reduce the harmonic generated during the operation of inverter,the space voltage vector pulse width modulation(SVPWM)technology is optimized,and the overall simulation model is built,which proves the superiority of the control strategy.Then,the various faults that may occur during the operation of five-phase induction motor are introduced.For stator inter-turn short circuit fault that may result in missing-phase fault,a diagnosis method is proposed based on the stator fault diagnosis method of three-phase induction motor.The simulation model is built,and the simulation verification is carried out.Finally,a mathematical model of the five-phase induction motor under the condition of missing one phase is established,and the pulsating component of the electromagnetic torque is deduced.A fault-tolerant control strategy is proposed to suppress the fluctuation of electromagnetic torque.The simulation results verify the feasibility of the proposed fault-tolerant technology.