Research On AC PMSM Servo System Speed Performance

With development of Power Electronics, Microprocessor and MotorManufacturing Technology, the performance of PMSM(Permanent MagnetSynchronous Motors) Controller is improved continuously and the controller isapplied in many fields such as industrial automation, national defence and so onPMSM is drawing more and more attentions due to abundant rare earth resourcesin China, manufacturing technology improvement and better performance thanother motors with hardware design, PCB layout and comprehensive and researchon speed performance included, the overall design of permanent magnetall-digital AC servo controller is implemented. The major works in this thesis areas follows.Vector control algorithm and implementation is introduced, speed andcurrent closed loop design is implemented utilizing traditional PI controller andhardware platform. Step response at different speeds is analyzed, theperformance of M/T method and T method in low speed condition is investigatedand relevant experiment data is collected.Speed and position information is captured by optical encoder, speedmeasurement error can not be neglected and controller performance is affected.After variable parameter PI controller has been investigated, controllerparameters in low speed are determined, position compensation is implemented,and speed control performance is improved significantly especially in low speedcondition.In response to these issues, speed observer is anal yzed and full-order stateobserver utilizing error of rotor position and angle is designed. The full-orderobserver is stable and convergent with approximate poles and its algorithm issimple and can be implemented easily.In this thesis, to improve controller performance in，condition further,variable moment of inertia is considered by principle of adaptive identificationwhile speed observer is working. And excellent controller performance isverified by simulation based on Matlab/simulink.