Research On PMSM Control Key Technology For Electric Vehicle

With the continuous update and stability of new energy vehicle platforms,as well as the influence and promotion of various environments(such as government interest subsidies,high oil prices caused by russia-Ukraine military conflict),electric vehicles are increasingly favored by the public.Among them,permanent magnet synchronous motor(PMSM)has become the mainstream motor because of its advantages of high power density,low noise,variable power factor and fast dynamic response.As motor control is one of the most important links in the stable and safe driving of electric vehicles,the research content of this thesis is permanent magnet synchronous motor control based on the background of electric vehicles,which can be divided into two parts and three aspects:Firstly,there are two parts: theory part and hardware platform part.The three aspects are the algorithm design of speed controller based on vector control under the theory part,the algorithm design without position sensor(position identification)and the hardware and software system design under the hardware platform part.Because of the excellent performance of permanent magnet synchronous motor under the vector control model and combined with the stability disturbance rejection required by the electric vehicle in the driving process,the sliding mode control principle is used in the key technology research of its speed controller.And in order to make better control performance,through relevant improvement process,put forward the exact feedback linearization high-order sliding mode control method,the simulation results show that this method makes the permanent magnet synchronous motor control performance better,have better dynamic response process of the system chattering is extremely weak,also let electric vehicles is more stable and comfortable.In view of the complex and changeable environment of electric vehicle,it will affect the detection position of mechanical position sensor is not sensitive or invalid,so the key technology of its position identification is studied and analyzed,and a high order sliding mode observer is designed to make electric vehicle run stably without position sensor control.However,under the background that the observer’s performance at zero low speed is not enough to make the electric vehicle run continuously and stably in the full speed domain and consume as little energy as possible,this paper proposes a control method combining the zero-low speed I/F algorithm and the high speed observer algorithm,and designs a smooth switching process between the two.The experimental results show that this method can keep the PERMANENT magnet synchronous motor running steadily in the full speed domain and make the electric vehicle based on permanent magnet synchronous motor run efficiently in the whole process without position sensor.Finally,around the DSP28355 digital signal processing chip to complete the actual system hardware platform design,and the use of Altium Designer drawing software to draw relevant circuit diagrams,including the main control circuit diagram,protection circuit diagram,detection circuit diagram,drive circuit diagram and various isolation circuit diagrams.Then this design,on the CCS software platform for programming,to achieve the overall operation of the actual system,for manufacturers to PMSM control driving electric vehicles,provides a strong practical significance.