Research On Double-plane Vector Control Technology Of Five-Phase Permanent Magnet Synchronous Motor

In some occasions where high power is needed,three-phase motors are often difficult to meet the requirements due to the limitation of rated power.Therefore,multi-phase motors are considered as the most potential alternatives to traditional motors.As the number of phases increases,so does the degree of freedom.Utilizing these characteristics,when designing a motor drive system,methods are more diverse and more flexible.In order to make the motor speed range wider and harmonic content controllable,this paper adopts the double-plane vector control technology.Because the response of the speed loop is not ideal,a flexible variable structure control algorithm(FVSC)is introduced.Finally,the motor experiment platform is built with TMS320F2812 as the core,and the control algorithm studied in this paper is implemented.The main contents of this article are as follows:Firstly,the electromagnetic torques of BLDCM and PMSM are analyzed,and a new type of five-phase PMSM(NFPMSM)is introduced.Afterwards,based on the classical theory of motor modeling analysis,the mathematical model of NFPMSM in the natural coordinate system is deduced.In order to constantize the time-varying parameters of the NFPMSM,the Park transformation of the N-phase system is introduced.The harmonic distribution of the five-phase system is analyzed emphatically,and it is concluded that the harmonics are distributed on three planes.Among them,the two planes contribute to the generation of the torque.Therefore,the double-plane mathematical model of NFPMSM is obtained through transformation.Then the double-plane vector control technology is studied in depth.It is pointed out that the implementation of the traditional single-plane two-vector SVPWM method is only effective in the ?1-?1 plane,but the vector in the ?3-?3 plane is in an uncontrollable state.Under this background,the realization method of double-plane four-vector SVPWM is presented.This new method makes the vector in the ?1-?1 plane and the ?3-?3 plane in a controllable state,and reduces the switching loss,making the waveform smoother.Because the ?1-?1 plane and ?3-?3 plane outputs are AC quantities,the d-q plane and d3-q3 plane outputs are DC quantities.In order to make it easier to observe the vector synthesis of the ?1-?1 plane and ?3-?3 plane,it is decided to observe the control effects in the d-q plane and d3-q3 plane.From the simulation results,it can be seen that the dual-plane four-vector SVPWM control algorithm has great flexibility,where large torque is needed,some harmonics can be added in moderation,and harmonics can be completely eliminated where torque smoothing is required.In addition,the speed loop is optimized,a new FVSC algorithm is introduced,and a speed controller is designed according to the characteristics of the NFPMSM.Finally,under the MATLAB/SIMULINK,the traditional PI control system is used as a comparison.It is proved that FVSC control is more stable than PI control without overshoot.Finally,the hardware and software components of the NFPMSM dual-plane vector control are studied.Experiments are carried out on the established NFPMSM experimental platform to verify the performance of NFPMSM startup,acceleration and load changes,as well as the control effect of FSVC.