The Research On Fault-tolerant Control Of Three Phase Permanent Magnet Synchronous Motor Based On Deadbeat Direct Torque Control

As the core of wind power generation,ship power,electrified transportation,aerospace,national defense and military industry systems,the shutdown or loss of function of motor system will seriously threaten the overall operation performance of major equipment,even bringing about fatal impact,and leading to catastrophic accidents.It is of great theoretical and practical significance to carry out the research work of motor system with high reliability and strong fault-tolerant performance so as to avoid the stop or loss of function caused by faults,which has strategic impact on national economic construction and national defense security.Three-phase permanent magnet synchronous motor(TP-PMSM)is widely used in electric vehicles,aerospace,robots and other fields of life or production because of its high power and high performance.Because the motor itself does not have fault-tolerant ability,it is of great significance to improve the reliability and fault-tolerance of the motor system from the two aspects of inverter and control method.At present,the fault-tolerant control of three-phase permanent magnet synchronous motor system at home and abroad is mainly based on inverters,so further research on fault-tolerant control algorithm of three-phase permanent magnet synchronous motor can further improve the reliability and fault-tolerance of the system.Direct Torque Control(DTC)has a "natural" fault tolerance and has been successfully applied to multi-phase permanent magnet synchronous motors.Traditional direct torque control of permanent magnet synchronous motor has the problems of large flux linkage and torque ripple and unstable switching frequency,while the deadbeat direct torque control,which is combined with deadbeat control and direct torque control,not only has fast dynamic response,but also has small fluctuation of stator flux and torque,good dynamic and static performance.Therefore,in order to improve the fault-tolerant performance of three-phase permanent magnet synchronous motor,combined TP-PMSM's fault mathematical model and deadbeat direct torque,the deadbeat direct torque fault-tolerant control of three-phase permanent magnet synchronous motor is proposed,which can achieve satisfactory dynamic and static performance before and after fault.on the basis of discussing the research status of fault-tolerant control of multi-phase permanent magnet synchronous motor and three-phase permanent magnet synehronous motor,the fault-tolerant control of the latter is thought to need further improving.To keep the motor under single-phase fault operating,a fault-tole'rant control based on deadbeat-direct torque and flux control(DB-DTC)of three-phase permanent magnet synchronous motor is proposed.Under faulty operation,this fault-tolerant DB-DTFC offers an independent regulation of the electromagnetic torque and the stator flux linkage by using the same torque line equation,stator flux linkage,and current observers adopted during healthy conditions,requiring very limited hardware reconfigurations.The proposed fault-tolerant DB-DTFC has been validated by simulation tests,confirming that the proposed fault-tolerant DB-DTFC ensures satisfactory faulty operations and drive stability,keeping limited the increment of computational efforts.What's more,the simulation results show that the input of decoupling resistance can restrain the ripple of motor torque and speed.