| The hoisting system driven by sectional permanent magnet linear synchronous motor is a new-fashioned rope-less hoisting mode which different from traditional hoisting system, which has the following advantages: simple structure, high efficiency, less energy, unlimited hoisting distance, velocity and other obvious advantages. It has excellent prospects for development. But the theory and control is not too mature and it is still at the experimental stage. The designers and users have been troubled by the out-of-step of hoisting system driven by sectional permanent magnet linear synchronous motor. In order to ensure system's security and reliable operation, and avoid the occurrence of enormous casualties and economic losses because of out-of-step, it is very necessary to take measures to prevent and control. The measures, that applied when the motor is at the state of out-of-step, are not only to avoid the occurrence of the accident, but also improve work efficiency. In this paper, based on the analysis of power angle characteristics and stability of permanent magnet linear synchronous motor, studying the impact of the power supply frequency and supply voltage on the operation stability of motor, and using fuzzy control theory to set up out-of-step preventive control strategy. The strategy introduces dual-mode fuzzy control structure, makes power angle stability margin as the controlling and adopts the strategies of changing the power supply voltage and operating speed to prevent the occurrence of out-of-step. Papers set up the model of the whole system using the simulation software of Matlab/Simulink, the results of Simulation demonstrate the feasibility and real-time of the control strategy. In this paper, the experiment was realized on the experimental device of the elevator which based on the industrial computer and PLC (IPC + PLC). Experimental results show that, the strategy can effectively improve system's stability and security, and reach the expected results.
|
PDF Full Text Request