Research On Open Circuit Fault Tolerant Control Of Open Winding Permanent Magnet Synchronous Motor

In the context of vigorously promoting energy conservation,emission reduction,and low-carbon travel,electric vehicles have shown a rapid development trend with their significant advantages such as zero emission,low noise and high efficiency.Compared with traditional motors,the open-winding permanent magnet synchronous motor used in this paper has high efficiency,high power density and strong reliability,and is especially suitable for driving electric vehicles.The motor drive system is a key part of an electric vehicle.The traditional motor drive system is powered by an ordinary voltage inverter.The output voltage of this power supply method is of poor quality,low energy utilization,and weak fault tolerance.The power supply method based on dual inverters has attracted more and more attention due to its advantages such as high DC power utilization rate,strong fault tolerance,and large output capacity.The seeding structure untie the Y-shaped(△-shaped)connection point of the stator winding of the normal three-phase motor,and the two ends of the stator winding are respectively connected to an independent standard inverter.This paper takes the open-winding permanent magnet synchronous motor as the research object,and conducts in-depth research on the fault-tolerant control of the open-circuit fault of the single-phase winding of the open-winding permanent magnet synchronous motor.The thesis first introduces the domestic and foreign research status of permanent magnet synchronous motors,open-winding motor control systems and fault-tolerant control of motor drive systems.Then the topological structure of the open-winding motor and its control strategy are introduced,and a mathematical model based on the open-winding permanent magnet synchronous motor is established.This paper introduces the working principle of the open-winding permanent magnet synchronous motor control system in detail.Based on the space vector pulse width modulation technology(SVPWM),the open-winding permanent magnet synchronous motor vector control system is constructed.Based on the Matlab/Simulink simulation platform,a simulation model for the normal operation of the open-winding permanent magnet synchronous motor vector control system is built,and the simulation results are compared with theoretical research to verify the feasibility of the control system.The thesis focuses on the research on the open-circuit fault of the single-phase winding of the open-winding permanent magnet synchronous motor.The fault-tolerant control principle is analyzed in detail,and a two-phase double H-bridge fault-tolerant control strategy is adopted.Based on this,an improved double The H-bridge faulttolerant control strategy suppresses the torque ripple of the motor.At the same time,based on the Matlab/Simulink simulation platform,a simulation model of open-circuit fault-tolerant control of open-winding permanent magnet synchronous motor singlephase windings is established.Combined with the analysis of theory and simulation results,the vector drawing of open-winding permanent magnet synchronous motor proposed in this paper is verified.A fault-tolerant control strategy for single-phase open-circuit faults in the system.Finally,an open-winding motor drawing system experimental platform based on DSP control is built,and the vector control system under normal operating conditions of open-winding permanent magnet synchronous motor and the fault-tolerant control system under the condition of single-phase winding open circuit fault are carried out experimental research respectively.The experimental results show that the openwinding permanent magnet synchronous motor control system has good dynamic performance and fault-tolerant operation capability.