Research On Permanent Magnet Brushless Motor Control System For Electric Vehicle

Applications of electric vehicles will help resolve the current issues humans ar e facing about environment, transportation and energy. As execution means widel y used in electric vehicles power systems, the control and drive technology of P MSM is hot in field of electric vehicles research. By reference literature and rep orts, this paper organizes and elaborates the development trends and application of permanent magnet brushless motor in the field of electric vehicles. Due to the difference of current drive mode, permanent magnet brushless motor divides into: brushless DC motor and permanent magnet synchronous motor. This paper studys and verifys the control technology of these two kinds of motors in control strat egy, drives, modulation and rotor position detection, etc. Specifically, the main w ork is as follows:(1) Establishment of brushless DC motor model; study the commutation techn ology, PWM drive technology and dual loop control strategy; analysis the reason that motor current waveform distortion problem due to the incorrect commutation signfrom BLDC with position sensor; gives the qualitative identification method, and puts forward the preliminary compensation scheme; analysis EMF zero cros sing detection method of three kinds of practical circuit in the position sensorles s BLDC.(2) Establishment of permanent magnet synchronous motor model; Study the relevant control strategy of sensorless permanent magnet synchronous motor oper ation in the whole speed range; Simulate above studies by Matlab. In particular, these technologies are:Two kinds of initial rotor position detection algorithm, pr e location algorithm and pulse injection method; Motor open loop starting schem e, which is I-F starting algorithm, using current closed loop to ensure stable star ting; Observation of motor speed in the middle and high speed area, which cont ains EMF integration method, sliding mode observer method, MARS, and curre nt closed loop observer method based on the motor electrical equations and moti on equations.(3)Design and debugging of a permanent magnet brushless motor control platf orm; main circuit is three-phase half-bridge circuit. main control chip is TMS320 F28035; detailed design and analysis about control hardware circuit parameters; r eliable design of software part flowchart based on modular software thinking; pr ogramming and debugging the system in the CCS system environment with relia ble detection, protection and control functions.