Fault Diagnosis And Fault-tolerant Operation Control Of Double Asynchronous Motor Speed Regulation System

In the fields of energy,machinery and aviation,it is often necessary to coordinate multiple motors,among which the double-asynchronous motor speed regulation system is the most typical.In the system,power electronics device is the core and the weak link,in the event of failure,will cause a system crash,cause potential safety hazard and huge economic losses,so the timely and accurate positioning fault tube and take the corresponding fault-tolerant operation is particularly important,this article for the dual induction motor speed control system fault diagnosis and fault tolerant operation were studied.The conventional current fault diagnosis method is only suitable for single tube fault and open loop control system.In view of the above problem,this paper proposes a fault diagnosis method based on phase current rectifier average,by introducing a nonzero symbol with conventional diagnostic variables,and simplify the process of fault diagnosis,expanding the difference of fault diagnosis and normal phase variable,can accurately locate fault tube in the closed loop control system,so as to achieve the aim of double tube can detect any faults.In the conventional fault-tolerant operation method,the current and torque are easily distorted during the switching process,and the reverse charging of the dc busbar capacitor during the high-speed switching process will lead to the high bus voltage.To solve above problems,and puts forward the switch in the operation of the fault tolerance method improvement,optimize the conventional fault-tolerant operation method switching sequence and use weak in running at a high speed magnetic induction electromotive force,reduce motor makes the switch in the process of the distortion current and torque is reduced,at the same time in the high speed switching process won't come to dc reverse charge,in the process of implementing fault-tolerant operation smooth switching.Simulation and experimental results show that the fault diagnosis and fault-tolerant operation method adopted in this paper can timely and accurately diagnose single-tube and double-tube open circuit faults,achieve smooth fault-tolerant switching,and thus ensure the stable operation of the system.