| Precision centrifuge is a large high-precision testing equipment which is used to label and test the inertial components. It works in extremely accurate environment and any minimal disturbance is likely to influence the speed accuracy. Owing to this kind of high precision feature, there exist two key problems when designing the precision centrifuge control system. Firstly, disturbance rejection problem; secondly, multi-sub-system coordinated control and real time response problem. This paper bases on precision centrifuge project of our lab, and study the two problems above.Firstly, the principle of the motor moment fluctuation subjected to periodical disturbance in precision centrifuge is analyzed. Mainly the mechanism of fluctuating moment occurrence is introduced, inherent physical and mathematical principle is probed in, synthesizing real system's features and requirements,the specific mathematic expression of fluctuating moment that affects the system most is obtained , and simulation experiment is done to test the impact on the system .Secondly, as far as the periodic feature of fluctuating moment is concerned, repetitive control theory is proposed. Further more, repetitive control system's stability ,tracking performance, disturbance rejection and robust stability are discussed and studied specifically. Based on these, the design method of repetitive control system is discussed and real system repetitive controller is given .The system debug result shows that the designed repeat-controller can reject fluctuating moment effectively and is better than the conventional controller in performance.Finally, for the precision centrifuge real control requirement, RTX-based real time control system designing and implementing method is studied. The architecture of Windows NT operating system and corresponding real time sub -system RTX, main function feature, respective communication mechanism and communication mechanism between are introduced. Windows NT operating system's defect and superiority in the respect of real time are described, and real time control system's software design is finished. |
