Position Sensorless Control Of Permanent Magnet Ac Servo System

The article devotes in the simulation and experimental studies of Position Sensorless Control for Permanent Magnet AC servo system, which is based on Sliding Mode Observer.First of all, the article introduces the Position Sensorless Control for Permanent Magnet AC Motor Using Sliding Mode Observer and the theory about sliding mode variable structure. And then, this article builds a simulated analytical model based on Matlab/Simulink to simulate a 1.6kw Permanent Magnet AC Motor. The simulation results show that when we use the theoretical parameters of Sliding mode observer, the reconstruction information acquisited of rotor position is not converge when it is light load, the error rather thick when heavy load. In succession, this article utilizes the simulation model to research the relationship between the parameter of Sliding mode observer and filter and position estimation accuracy. Finally, the article registers an improved Sliding Mode Observer.Subsequently, the article introduces the hardware structure and the parameter of Controlled object of system prototype. Then, introducing the software design and architecture. The article emphasizes the realization of digital PID regulator in system prototype software, data processing and SVPWM algorithm.In the end, the article makes an experiment research. Aiming at position sensor's system, the article makes a relative analysis of the influence of formal PI adjuster, variable-structure PI adjuster and differential feedback PI adjuster to response time and overshoot of dynamic performance when no loading. Then, the article makes an further research on control strategy of no-sensor controller and discusses the conclusion of Position and speed reconstruction from Sliding Mode Observer under different load and rotational speed. Aiming at Zero-Speed Start, this article raises a method which switches between variable-speed starting and frequency modulation starting.