Implementation Study Of Position-sensorless Vector Control System For Fault-tolerant Permanent Magnet Motor

Motor and the control system of it are the core parts of the electric drive,they are ofen malfunctioned due to various reasons in some times.Even if the motor and control system has a short time of failure,which will lead to incredible loss,especially in medical,nuclear industry and other areas of high security requirements.The permanent magnet fault-tolerant motor has the characteristics of high reliability and fault tolerance,which is a significant value of the above fields.At present,most of people use the mechanical sensor to obtain the rotor position and speed information in the permanent magnet fault-tolerant motor control system.Although these sensors can provide more accurate data information,it reduces the reliability of the system at the same time.Therefore,the sensorless control technology of permanent magnet fault-tolerant motor will be the research hotspot in motor control field.This paper mainly studies the position sensorless control technology of fault-tolerant permanent magnet motor.Firstly,it systematically introduce the basic structure and mathematical model of the six-phase permanent magnet fault-tolerant motor,the structure of vector control system,the control strategy of one-phase fault-tolerant in open-circuit or short-circuit,the current hysteresis tracking control strategy and so on.Secondly,it also focuses on the control theory of sliding mode variable structure,proposed the rotor position estimation algorithm of permanent magnet fault-tolerant motor based on sliding mode observer with the mathematical model of permanent magnet fault-tolerant motor.Then,according to the structure characteristic of the six-phase permanent magnet fault-tolerant motor,the control center of hardware experimental platform based on TMS320F28335 DSP is put up,including six-phase H-bridge inverter circuit,voltage and current detection circuit.And the software of control system is designed and debugged.Finally,do experiments on the platform when the motor works in normal operation and one phase open-circuit.Through the experiments,the results verify the correctness and feasibility of the rotor position estimation algorithm.