Research Of Out-of-step Prevention Control For Permanent Magnet Linear Motor Based On Fuzzy Neural Network

At present, the permanent magnet linear synchronous motor (PMLSM) is of highresearch value and application prospects in vertical transportation system. It has notablefeatures of high efficiency, energy saving, simple structure, unstinted running distanceand speed, no pollution and low noise. However, PMLSM inevitably encounters variouskinds of turbulences in operation because of the unnecessary mechanical transmissiondevice. In the practical operation process, if the motor is out-of-step, the mover and thecage will drop down quickly by gravity, which causes severe accidents. It is also thecrucial question that persecutes the designer and the user. Therefore, the uses of accurate andreliable detection means and the application of the new and effective control strategyare of great significance for the steady and safe operation of PMLSM withmulti-segment primary driven lifting system.The key parameters of out-of-step prevention and control are getted and the faultphenomenon information is proposed in this paper by means of analysis of fault reasonsfor out-of-step and symptoms of phenomenon information.Control scheme and strategy are established for the prevention of out-of-step. Thestrategies adopt dual-fuzzy neural network controller, which uses the power anglestability margin as control parameter by changing supply voltage and motor speed toprevent the out-of-step. A nonlinear function which was approaching to1as the powerangle stability margin increased was imported to combine the fuzzy controller with theneural network controller, so that could improve not only the system dynamic responsecharacteristics and the steady accuracy but also its adaptive ability.The out-of-step prevention and control system simulation model is established andsimulated under the software of MATLAB/SIMULINK. The results of simulation andexperiment were provided to demonstrate that this novel control strategy could preventout-of-step effectively and keep PMLSM maintaining stable operation.We make the out-of-step prevention and control strategy to experiment using the devices of the horizontal-moving PMLSM experimental devices with load1000kg,3m.The results of the experiments demonstrate that both two control strategies have bettercontrol quality.