The Application And Research Of Fuzzy Control Theory In The Active Magnetic Bearing

This paper applied the fuzzy control theory into Active Magnetic Bearing (AMB), AMB is a non-linear system, has the character of instability,strong peg-top coupling and difficulty to build its mathematical model. Fuzzy control don't need the precise mathematical model of the system, to non-linear system or the system that have uncertain description in the input or operating, which have good performance in dynamic speciality and good adaptability while the parameter changing.Two controllers were proposed in this paper: one is Fuzzy-PID mulriple controller. The fuzzy control is used when the error is large, while the PID control is used when the error is small. This controller combines the advantages of the two control modes, whose key lies in the choosing of the switch value and the proportion gene. The other one is Optimized Fuzzy Controller based on interpolation on-line.This controller imports the arithmetic of interpolation on-line in the fuzzy control, and also adding one integral operation on the out value. The introduction of interpolation arithmetic is equivalent to have infinitude partition in the defined fuzzy fields, which overcome the steady trembling phenomenon arose by the measure error from fundamental. Both of the two arithmetic got satisfied result in the static and dynamic suspension of the AMB system.The experiment result indicates that the arithmetic proposed in this paper is more agile and adaptable. To the complex object of AMB, the experiment got satisfied result in the aspects of responding velocity and steady precision.