Research On The Flux-Weakening Control Of Permanent Magnet Synchronous Motor Of Hybrid Electric Vehicle

Permanent Magnet Synchronous Motor(PMSM)has been widely used in the driving system of hybrid electric vehicles due to its good torque output characteristics and speed regulation performance.The drive system of hybrid electric vehicles requires a wide range of motor speed regulation,while the Maximum Torque Per Ampere control can only control the motor running below the base speed,so the flux-weakening control strategy that can expand the range of motor speed regulation has become a research hotspot in the field of electrical transmission.In this context,it is of great theoretical significance and practical value to study IPMSM drive system with stronger speed-expanding ability.Interior Permanent Magnet Synchronous Motor is taken as the research object,and the flux-weakening control strategy of IPMSM is studied.The main research contents are as follows:(1)The research background and significance of PMSM control technology and parameter identification method are briefly described.Based on the motor control strategy,the research status of flux-weakening control at home and abroad and some common parameter identification methods of PMSM are introduced.(2)The mathematical model of PMSM in different coordinate systems is established.The flux-weakening control theory of PMSM is introduced in detail,and the operating region and constraints of PMSM are analyzed.According to the research background of the subject,the motor control strategy is determined:MTPA control and flux-weakening control.Based on the principle block diagram of the flux-weakening control of IPMSM,the simulation of the flux-weakening control of IPMSM is realized in the MATLAB simulation environment,and the feasibility of the flux-weakening control strategy is verified by the simulation results.(3)Sliding mode variable structure control(SMVSC)is combined with fuzzy Control strategy to design a fuzzy Sliding Mode controller.The coefficients in front of the symbol function are adjusted online by fuzzy control strategy,which can effectively enhance the system's ability to resist load disturbance without aggravating the chattering of sliding mode.The system simulation results show that the designed fuzzy sliding mode controller can effectively enhance the anti-load interference ability of the system,and make the system obtain excellent static and dynamic performance.(4)Based on Popov integral inequality,an adaptive law for online identification of IPMSM parameters is derived,which realizes the online identification of stator resistance Rs,d-q axis inductance Ld,Lq and permanent magnet chain ?f.In the MATLAB/SIMULINK simulation environment,a simulation model for IPMSM parameter online identification was built.The simulation results showed that the parameters identified online had higher accuracy,and the motor speed response curve had faster response speed,can achieve adaptive control.