Control Schemes Of Start-up For Elevators Based On Permanent Magnet Synchronous Motor

With the development of the living quality, safety and stability of elevators are valued. Permanent Magnet Synchronous Motor(PMSM) representing an advanced technology in the elevator system becomes the mainstream. The thesis mainly studies on start-up for elevators based on PMSM.The main research on the initial angle acquisition and start-up torque compensation is proposed in the thesis. Based on mathematic model of vector control on PMSM, controller of dual closed loop is designed and parameterized. Space Vector Pulse Width Modulation(SVPWM) and parameter tuning of current loop is proposed. A main problem on how to obtain initial rotor angle at start-up is solved by high frequency signal injection. Compared with pulsating voltage method, the method of rotating voltage is more suitable for elevators. According to the theoretical derivation of magnetic saturation effect, d axis is chosen for voltage injection. Analysis of the load torque at start-up, a control scheme of starting torque for elevators without a weight transducer is proposed in this paper. The high accuracy speed measurement and adjusting method of PI controller combining improved sliding mode observer are established to make the system stable and improve the dynamic performance of the motor starting torque for elevator. Finally, the result of stimulation and experiment on a permanent magnet synchronous motor verify the previous mathematic model and theoretical analysis. The work is summarized and the prospect is put forward...