Research On Control Strategy Of Internal Permanent Magnet Synchronous Motor

The shortage of petroleum resources and environmental pollution have restricted the development of Chinese auto industry,for which the rapid rise of electric vehicles brings new hope for.To make the electric vehicle with the dynamic performance of the traditional fuel vehicle and to conquer the key technology in the drive system of the electric vehicle,the Interior Permanent Magnet Synchronous Motor(IPMSM)with the high power density and the wide speed range has been taken as the research object,of which driving system is made a deep research on the control strategy.Firstly,a mathematical model of IPMSM in three-phase stationary coordinate system is established,of which quadrature-direct axis current was decoupled by the transformation of Clarke and Park with four commonly used IPMSM vector control technologies analyzed and compared.A simulation model of id=0 and Maximum Torque per Ampere(MTPA)based on Space Vector Pulse Width Modulation(SVPWM)was built in the Simulink,and the superiority of MTPA was verified.Secondly,Extending the constant power speed range of the motor to improve the torque output capacity of the motor at high speed,the flux-weakening(F W)control of IPMSM was further study.Combined with the constraints of voltage and current under different speed,deduced the weak magnetic control algorithm.Using look-up table made the real-time of algorithm improved greatly,which reduced the requirement of the main control chip and realized the smooth transition between MTPA and flux-weakening control.Then,in order to improve the motor torque control performance,adopting the diagonal matrix decoupling control method with adding a decoupling matrix in the current motor control loop could realize the dynamic decoupling of quadrature-direct axis current.Through comparison and analysis with the feedback decoupling method,it is verified that the method proposed has better robustness when the motor parameters are disturbed by the external environment.Finally,the hardware test platform with TMS320F28335 as the control core was set up,with the circuit of signal detection,IGBT drive and communication being designed.On the basis,a IPMSM vector control program was developed.The test results verify the feasibility of the control system.