不確定性系統之滑動模式控制實際設計

Sliding mode control for uncertain systems-some practical design

張欣宏(Shin-Hung Chang)

指導教授 ： 黃英哲

共同指導教授 ： 郭姿君

元智大學/電機通訊學院/電機工程學系/博士(2007年)

https://doi.org/10.6838/YZU.2007.00323

摘要

本論文提出數種改良型滑動模式控制之設計策略來改善傳統滑動模式控制所存在的一些缺點及限制，並且提高了系統的運算效率。傳統滑動模式控制是設計適當的控制力，然後在指定好的路徑下驅使系統狀態軌跡由初始狀態值朝向原點移動。其缺點在於控制輸入包含高頻不連續切跳現象，而此切跳現象在硬體電路實現上有其困難性存在。再者另一個限制是當系統在滑動模態下，其系統閉迴路極點存在一個以上於原點。因此，在本論文中吾人提出數種改良型滑動模式控制之設計策略，其目的除了改善了輸入切跳現象，可任意指定所有閉迴路極點，無需量測系統狀態外，最後吾人也提出另一種提高系統運算效率的方法。本論文所提出之滑動模式控制法整合了適應性控制，根值指定法，以及查表法等。藉由電腦模擬及實驗結果驗證了所提出之控制方法能有效達成上述的目地，並且也保證了系統對於存在參數擾動及外在干擾下的穩定性及強健性。

關鍵字

不確定性系統, 滑動模式, 適應性, 根值指定法, 查表法, 強健性

並列摘要

In this dissertation, various sliding mode control methods are proposed to improve some shortcomings and limitations in conventional sliding mode control and further to reduce consumption time and prime cost. Conventional sliding mode control uses a suitable control law to drive the system states from initial position to the origin along a user-specified path.　Unfortunately, a high frequency and discontinuous control action exists in conventional sliding mode control. Then, the chattering owing to the discontinuous control law is very difficult to be implemented in most applications. Moreover, a limitation is that one or more closed-loop poles in the sliding mode are located at the origin. For this reason, this dissertation proposes various modified sliding mode control strategies to eliminate the chattering, to assign freely all closed-loop poles, to eliminate states observation, and to increase computation efficiency. In summary, the proposed modified sliding mode control methods integrate adaptive control, pole assignment, output sliding control, and look-up table techniques. Through the simulations and experiments, the modified sliding mode controllers have been shown to achieve the demanded goals with satisfactory control performance and to guarantee the system robustness under parametric variations and external disturbances.

並列關鍵字

Uneertain systems, sliding mode, adaptive , pole assignment, look-up table, robustness

參考文獻

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