Research On Vector Control Strategy For Integrated Drive Of Five Phase Permanent Magnet Synchronous Motor

The integrated design of motor driver is an important technical route to meet the high power density,high efficiency,low cost and high integration of electric vehicles.Five phase permanent magnet synchronous motor has the advantages of high power density,small torque ripple,suitable for low voltage and high power,and fault-tolerant control,so it has a broad application prospect in electric vehicle drive system.In this paper,based on the integrated drive platform of SiC devices,considering the influence of the third harmonic,the single plane two-dimensional current closed-loop vector control,double plane four-dimensional current closed-loop control and single-phase open circuit fault mode vector control strategy of five phase permanent magnet synchronous motor are studied.Firstly,this paper studies the vector control strategy of five phase permanent magnet synchronous mo to.Considering that there are two more harmonic components in the five phase permanent magnet synchronous motor drive control system,there are two different control strategies,single plane control and double plane control.In order to solve the problem that the third harmonic current can not be controlled by closed-loop control in the single plane vector control,this paper studies the vector pulse width modulation(SVPWM)algorithm in the two planes.In the fundamental and harmonic sub planes,four adjacent vectors are used to synthesize their reference vectors without interference,and the centralization idea is used to unify the action time of each vector.It not only ensures that the output modulation voltage is constant,but also reduces the harmonic component and realizes the vector pulse width modulation of the dual plane.Secondly,aiming at the most common single-phase open circuit fault of five phase motor,based on the principle of keeping the fundamental magnetomotive force unchanged,the reduced rotation transformation matrix is derived,and the fault-tolerant decoupling model of five phase motor under single-phase open circuit fault mode is obtained.In the case of single-phase open circuit fault,the neutral point of motor winding is shifted,so it is not easy to get the PWM algorithm under single-phase open circuit fault.The SVPWM algorithm for single-phase open circuit fault is derived by using the calculated opposite potential of fault phase to compensate the voltage in static coordinate system,The vector pulse width modulation under single-phase open circuit fault is also realized by using centralization idea to coordinate the action time of each vector in two subspaces.Finally,an integrated driving experimental platform based on SiC devices is built.By improving the structure of integrated driving,the parasitic parameters are reduced,and good SiC driving performance is obtained.Based on the main control chip of DSP+FPGA,the algorithm of single plane adjacent four vector SVPWM,double plane PWM and single-phase open circuit fault PWM are tested.