Research On Permanent Magnet Synchronous Motor Control System Of Electric Vehicle

The automotive industry had made indelible contributions to the development of the world economy,but at the same time it had also brought a series of problems,such as environmental pollution and energy shortage.In recent years,the problem of smog in our country had become increasingly severe,which had seriously affected the living environment of residents.Fuel vehicles consumed large amounts of petroleum resources,causing severe challenges in the energy sector.Therefore,looking for new forms of energy instead of oil to provide power for cars had become a trend.In this situation,the development of new energy vehicles had ushered in a good opportunity.As the main force of new energy vehicles,electric vehicle had received strong support from national policies.As one of the core technologies of electric vehicle,motor drive technology had become the focus of research.By comparing the four types of drive motors used in electric vehicle,surface-mounted permanent magnet synchronous motor was selected as research object.Firstly,based on the two-level SVPWM technology,the implementation of the three-level SVPWM technology was introduced;Then,the mathematical models of permanent magnet synchronous motor in different coordinate systems were deduced.The permanent magnet synchronous motor vector control system was designed with the(28)0di control strategy.The Matlab simulation showed that the designed vector control system had good dynamic performance and robustness to load disturbance.In addition,the position sensorless based on sliding mode observer was designed to estimate the rotor position and velocity of permanent magnet synchronous motor.In view of the shortcomings of the traditional sliding mode observer control system,the sigmoid function was used as switching function to effectively suppress system chattering.The phase-locked loop technology based on the principle of high-precision phase tracking was used to estimate the rotor position,which eliminated the filter and avoided delay effect caused by the filter.The Matlab simulation showed that the designed sliding mode observer could make the control system run reliably and accurately estimate the rotor position and speed.