Fuzzy Adaptive Control Of The Linear Elevator

Recent years, there are more and more super-skyscrapers with the rapid development of society. The elevators that are indispensable in super-skyscrapers developed more and more quickly. The severe challenge of traditional rope lifting system had been proposed because of super-skyscrapers development. So it is important that to design the new lifting system, and the elevator driven by linear motor is put forward.The linear motor is drive device that can change electric energy into linear motion mechanical energy. It can be used in many occasions that rotary motions are transferred into linear motions. The middle institution can be omitted thus the whole institution can be simplified. There has been a decrease in the work of the whole system maintenance and repair, an increase in system reliability, and easy controlled. The whole system efficiency can be improved in suitable situation. Therefore the linear motor will be widely used in so many fields such as transportation, industry, and national defense. The linear elevator is one point.This article adopts permanent magnet linear synchronous motor drive elevator. And the primary of permanent magnet linear synchronous motor is fixed in the hoist, and permanent magnet body is fixed on the cab. But as the iron core of permanent magnet linear synchronous motor is broken there will be ending-effect. Vertical ending-effect can cause the linear motor thrust ripple and then influence the elevator sense of comfort. This article put forwards the control method of adaptive-fuzzy-PID, which is applied to permanent magnet linear synchronous motor drive elevator system.Fuzzy control method has strong robust, and is a non-linear control method. This control method has a less dependence on target models and is suitable for uncertainty system and non-linear system control. But fuzzy control also has defect, such as the fuzzy rules are obtained by experience and expert knowledge. This cannot ensure that the rules are optimal and affect the control quality. So fuzzy control develops towards adaptive control. Adaptive control can adapt to the variation of object and disturbances through modifying its character. The adaptive-fuzzy-PID combines the advantages of adaptive control and fuzzy control. This method is not restricted by the mathematics model and has the ability of adaptability. It can inhibit the vibration because of linear motor end-effect and achieve the control purpose. The elevator will operate smoothly and comfortable. The elevator operation efficiency can also be improved. The simulations show that the adaptive-fuzzy-PID control method can response quickly and has good tracking ability. The system can become stable quickly when there are disturbances. So the elevator cab will become more comfortable and suitable for people.