Research On The Control Of Permanent Magnet Synchronous Wheel Motor Of Electric Vehicle

Since the mid of the last century, the permanent magnetic material is used in the manufacture of motors, and with the rapid development of power electronics and microelectronics technology for permanent magnet synchronous motor provides a broad application space. At the same time, the rapid development of the automotive industry, environmental issues more and more attention, in order to solve the above problems, and significantly improved fuel economy, there is no doubt you can use electric vehicles to achieve the goal.Permanent magnet synchronous motor with its small size, high power factor and the structure is simple, flexible, etc., has become one of the main motors of electric vehicle drive system.Considering the electric car on the wheel motor starting torque, power density, reliability, high performance requirements, the choice of the motor on to do a comparison. From the motor body to compare the reliability of permanent magnet synchronous motors and asynchronous motors equivalent, but because of the flexibility of permanent magnet synchronous motor structure, easy to implement direct drive load, eliminating the gearbox reliability is not high and the high failure rate of conventional motor bearings: greatly enhanced the reliability of the transmission system. Based on comparison, select a permanent magnet synchronous motor as the hub motor of choice, and described in detail.In this paper, the integral sliding mode control algorithm and three-level inverter is jointly controlled permanent magnet synchronous motor. Sliding Mode Control is a special type of non-linear, non-continuity control. This control strategy that special "Structure" system is not fixed, but may be in a dynamic process, purposefully changing according to the current state of the system, forcing the system in accordance with a predetermined "sliding mode" state trajectory. Meanwhile, China is a large energy-consuming countries, the three-level inverter has improve energy efficiency, reduce harmonics endanger other advantages. In this paper, the system selection integral sliding mode algorithm is robust, and three-point advantage by controlling the inverter save energy, improve system reliability needs. Finally, Matlab / Simulink and PMSM test bench proved the feasibility of the method.The main innovation of this paper:1. This article uses the feedback control 0di ? to complete the current vector decoupling.Traditional control 0di ? method only will be zero by proportional integral action data input to the coordinate transformation module, but the internal parameters of the permanent magnet synchronous motor is likely to be affected by temperature drift, it cause id current feedback is not accurate。In this paper,we make the value di 、qi 、? of the motor output feedback to system, dynamic performance is better.2. Permanent magnet synchronous motors with nonlinear, strong coupling and parameter uncertain characteristics,so we are using integral sliding mode control algorithm to control the motor,Motor running with a certain self-regulatory function and robustness in a different operating state; and to meet energy efficiency, reduced demand for harmonic harm inverter SVPWM technology chosen to support the three-level inverter improve motor control performance, better torque to achieve fast and accurate tracking control, reduce torque ripple goal.