Research On Positionless Sensorless Control System For Micro Electric Vehicle Drive Motors

In recent years,in response to global warming and energy crisis,China has proposed the "dual carbon" plan,demonstrating China’s responsibility as a major country in leading the process of global sustainable development.At present,vigorously promoting energysaving and low-carbon transportation has become an important strategy to achieve the goal of "dual carbon",and micro electric vehicles have good market prospects with the characteristics of green,economical and convenient in low-carbon vehicles,but micro electric vehicles have problems such as unsmooth driving and poor anti-interference ability during driving.In addition,the drive motor of the vehicle often uses mechanical sensors to obtain rotor position and speed information,and mechanical sensors take up additional vehicle space,increase costs,and reduce the reliability of the drive system.In order to solve the above problems,at the same time improve the economic benefits of micro-electric vehicles and the reliability and stability of micro-electric vehicles under operating conditions.In this paper,Permanent Magnet Synchronous Motor(PMSM)is used as the micro electric vehicle drive motor to carry out the research on the control of micro electric vehicle drive motor without position sensor,and the main contents of the research are as follows:Firstly,this paper introduces the definition of micro-electric vehicles and the selection of drive motors,and matches the parameters of the drive motors with reference to the performance parameters of micro-electric vehicles on the market.At the same time,the mathematical model of PMSM is analyzed,and the PMSM vector control model is constructed,which provides conditions for the research of PMSM sensorless control.Second,in the state of zero low speed,this paper designs a rotating high-frequency signal injection method to detect the rotor position and speed information of the motor.In view of the problem of position information lag caused by multiple filters in the rotating high frequency,the bisecond-order generalized integrator(SO-SOGI)is used to improve,and the control model is simplified to omit the low-pass filter,which solves the problems of speed jitter and rotor position hysteresis at low speed,improves the accuracy of rotor position detection during low-speed operation of micro-electric vehicles,and ensures the smooth operation of the vehicle at low speed.Third,in the medium and high speed state,this paper designs and studies the control of sliding mode observer.Aiming at the problems of jitter and weak robustness in the second-order sliding mode observer,a new full-order sliding mode observer is established by using PMSM extended back EMF,and fuzzy control is designed to adjust the sliding mode gain,and the switching function and phase-locked loop are improved,which improves the accuracy of rotor position and speed information detection and solves the jitter problem caused by the second-order sliding mode.Enhanced the reliability and robustness of micro-electric vehicles in medium and high-speed operation.Finally,in this paper,an improved weighted switching composite method is used as a control strategy for composite control in order to realize the positionless sensor-free control of micro-electric vehicles in the full speed range.And the hardware circuit design and software process design of PMSM positionless sensor control.The feasibility of PMSM positionless sensor control at full speed is verified.Figure [93] Table [10] References [85]...