Research On Parameter Identification And Regulator Design Of AC Servo System

Permanent magnet synchronous motor (PMSM) are now widely employed inhigh-performance servo system and other industries due to simple structure, reliableoperation and high efficiency etc, but the variation of motor parameters will seriouslyaffect its control performance. So it is important to study motor parameter identificationtheory for the development of high-performance servo system.0n the basis of studying PMSM mathematical model and control strategy, a rotor fluxoriented vector control strategy is adapted, and detailed analyze the principle of the spacevector pulse width modulation (SVPWM).According to the PMSM speed loop and currentloop equivalence principle and classical control theories, the PI regulator parameters of thecurrent loop and speed loop are designed. The simulation model of servo system isestablished by Saber Designer software, and simulation researches were done withdifferent structure of PI regulator, the simulation results proved the optimizedde-saturation PI algorithm that has a good dynamic performance and steady-stateperformance.After introducing and comparing the current mainstream motor parameteridentification method, this paper presents a technique of the inertia and load torqueidentification based on the dynamic equations of the motor, by mathematical derivation,get the recursion formula of inertia. The parameter identification sub-system simulationmodel is set-up using Saber software. The validity and effectiveness of this method areconfirmed by simulation results. When the whole inertia changes, it maybe make badeffect to the performance of controllers which have been well optimized and tuned.Therefore, to achieve the regulator parameters self-adjusting, the relationship betweenspeed loop PI parameters and inertia is deduced on the basis of classical control theories.The experimental results proved the servo system which has been adjusted having bettercontrol performance.