Research On Active Disturbance Rejection Control And Fault Tolerance Technology Of Six-phase Permanent Magnet Synchronous Motor

In some occasions that require high power level,control performance and reliability,the traditional three-phase motor cannot meet the demand due to its own limitations.The multi-phase motor has the advantages of high efficiency,small torque ripple,and strong fault-tolerant operation ability.Therefore,it has broad application prospects in areas with high reliability and precision requirements such as ship propulsion and aerospace.Due to the strong coupling and uncertainty of the mathematical model of the motor,and load disturbance during operation,which affect the performance of the speed regulation system,the control algorithm is required to have good anti-disturbance capability.Based on the above background,this dissertation takes the dual Y shift 30° six-phase permanent magnet synchronous motor as the research object,and conducts in-depth research on its space vector modulation technology,auto disturbance rejection control technology and fault-tolerant control.First,the mathematical model of a six-phase permanent magnet synchronous motor with a double Y shift of 30° in the natural coordinate system is established,and then the mathematical model in the rotating coordinate system is obtained by decoupling the transformation matrix and the PWM modulation of the six-phase inverter is obtained.Technology for research.When the two-vector SVPWM algorithm used in the traditional three-phase motor is directly applied to the multi-phase motor,the voltage component on the harmonic plane cannot be controlled,resulting in a large stator harmonic current.In this dissertation,a four-vector SVPWM modulation strategy based on virtual voltage vectors is used for vector control of six-phase motors,which can reduce the current harmonic contentwhile ensuring small switching losses of power devices.Secondly,the vector control system of six-phase permanent magnet synchronous motor with auto disturbance rejection controller for speed loop is analyzed.The principle and composition of the auto disturbance rejection control technology are introduced.In view of the problem that there are many parameters in the auto disturbance rejection controller and the tuning is difficult,the auto disturbance rejection controller is linearized.The speed loop linear auto disturbance rejection controller under the vector control theory of six-phase permanent magnet synchronous motor is designed,and the selection method of the speed loop linear auto-disturbance rejection controller is also analyzed.Thirdly,the magnetic potential of the six-phase permanent magnet synchronous motor in the normal operating state and the lack of phase F operation is analyzed,and based on the principle of unchanged magnetic potential before and after the fault,the fault-tolerant operation strategy of the F phase after an open circuit fault is studied and proposed Two fault-tolerant operation strategies,with minimum stator copper loss and maximum output torque,optimize the remaining phase currents to achieve stable operation of the motor after an open-circuit fault.Finally,based on the DSP chip,the design of the hardware circuit of the control system and the writing of the software program are carried out,and an experimental platform is set up for experiments on this basis.The analysis of the experimental results proves the validity and feasibility of the theory studied in this dissertation.