- 期刊
CONTROL SCHEME FOR TIME DELAY SYSTEM STABLE REGIONS OF ACTIVE MAGNETIC BEARING SYSTEM WITH D-PARTITION TECHNIQUE
摘要
Among all the control algorithms of active magnetic bearing system, the proportional- integral-derivative (PID) control algorithm is simple, adaptable and mature, and has been widely used in active magnetic bearing systems, usually as the main controller of the system. This article introduced a methodology of finding all the stabilizing parameter set of PID controllers for active magnetic bearing with time-delay by satisfying a robust performance constraint. The H-infinity index of multiplicative weight uncertainty on the basis of robustness stability condition of closed loop system was first given by small gain theorem. Then, the parameter boundaries with the expected decay ratio index of PID controller were derived based on the boundary crossing theorem with D-partition Technique. Inverse multiplicative modeling is used to describe the uncertainty of unstable perturbed system. A key advantage of this procedure is that it only depends on the frequency response of the system and does not require the plant transfer function coefficients. The simulation and experimental results prove the effectiveness of the design method adopted in this paper. The method can also be extended to other industrial control systems.