Reconstruction Of Phase Current Based On Single Current Sensor And Five-arm Dual-motor System

Permanent magnet synchronous machine(PMSM)has the advantages of high power density,high reliability and high efficiency,which is widely used in industrial robots,CNC machine tools and other occasions requiring high control accuracy.In the control of dual PMSM,fl-vsi(five leg voltage source inverter)is a better fault-tolerant scheme.In vector control of permanent magnet synchronous motors,two current sensors are often used to measure the phase current to complete the closed-loop control of the motor.The dual-motor system requires at least four current sensors to obtain phase current information,which increases the cost and volume of the system.In this paper,from the perspective of reducing the number of current sensors to reduce costs,a diagonally compensated measurement vector insertion method is proposed to complete the reconstruction of phase current,and the phase current reconstruction of the five-arm dual-motor system is studied in depth.main tasks as follows:First,mathematical modeling of the five-arm inverter dual motor system.The mathematical model of the five-bridge-arm dual-motor system is analyzed and the coordinate transformation matrix is derived,and the mathematical model of the dual-motor in the two-phase rotating coordinate system is obtained.Secondly,the vector control algorithm of the five-arm inverter dual motor system is introduced.The mathematical model and the voltage vector output from the five-leg inverter are introduced,the basic principles of the half-cycle control method are studied,the working time of each effective voltage vector in each control period is summarized,the sampling time is selected,and the effective voltage vector is used.The sampling method completes the phase current reconstruction work of the single motor system and the dual motor system,and summarizes the reconstruction blind area of the effective voltage vector sampling method.Thirdly,the phase current reconstruction principle of the triangle measurement vector insertion method in the five-bridge dual-motor system is studied,and the triangle current vector sampling method is used to complete the phase current reconstruction of the two-motor system,and the reconstruction blind zone is eliminated.On this basis,the diagonal compensation measurement vector sampling method is used to complete the phase current reconstruction with higher accuracy.Finally,the phase current reconstruction simulation model of the dual-magnet synchronous motor system of the five-bridge inverter is built.The reconstruction of the effective voltage vector sampling method of the dual-motor system is simulated,and the phase current reconstruction of the triangular measurement vector and diagonal compensation measurement vector sampling method is simulated and verified,and the two reconstruction methods are compared.specialty.The simulation results verify that the phase current reconstruction method of diagonal compensation measurement vector sampling proposed in this paper is effective and feasible.