Starting Control System Of Wound Rotor Permanent Magnet Motor

Induction motor can improve the heavy-duty performance with the rotor resistancechopper control, but the efficiency and power factor of asynchronous motor will decreaseobviously with the reduce of the load rate. Thought line-start permanent magnet synchronousmotor (LS-PMSM) can keep good performance in steady-state operation, the torque is smalland the current shock is obvious in starting process； Wound-rotort permanent magnet motor(WR-PMM) combines the advantages of both the wound rotor asynchronous motor andLS-PMSM. For the disadvantage of the large current and torque shocked evidently in startingprocess of the new type motor, combining the advantage of its rotor can be controlled byexternal resistance, this paper designed starting control system of Wound-Rotor PermanentMagnet Motor.This paper firstly combined with the particularity problem of the starting process ofWR-PMM，studied the design of the motor characteristics; Gave an overall designing idea ofthe WR-PMM and completed the design of a7.5kW prototype firstly; Study on startingcharacteristics of the prototype, focuses on the analysis of torque and locked rotorcharacteristics, and carry on the modeling and simulation. Then, confirmed the starting controlchopper adjustable resistance required by the system scheme, established quasi dynamicmathematical model of chopper adjustable resistance in starting control process; Through thewinding conversion and analysis of motor equivalent circuit, got the DC side chopperadjustable resistance circuit model; Quasi-time optimal control in starting process was putforward to WR-PMM its own performance，and accomplished the chopper resistance selection;Completed the circuit design and component selection of starting controller, and writingsystem control program. Finally, built a prototype starting control experiment platform anddebugged the whole system，then conducted experiments on steady-state performance and thestarting performance; experimented on the same power level of the LS-PMSM and woundrotor induction motor, then compared and analyzed the experimental results.The experiment results show that using quasi-time optimal control of WR-PMM instarting process, the effect of motor current suppression is obvious and torque shock reducessignificantly; The time of starting and pull in synchronous speed reduce greatly, the starting of motor is more faster and smoothly; WR-PMM achieved the quasi-time optimal control ofWR-PMM in starting process.