Comparative Study on Active Control Algorithms through Weighting functions

가중함수에 따른 능동제어 알고리듬의 비교 연구

The cost function consists of the weighting functions concerning the structural responses to be controlled and the controller capability. Therefore, the control efficiency depends on the characteristics of the weighting functions. The objective of this paper is the comparative study of the time domain control strategies of LQR and LQG and the frequency domain strategy of H₂ by setting the equivalent weighting functions to the all control strategies. As a result of analysis, LQR strategy is found to be more efficient than other strategies in terms of the response reduction. but the control force is found to be a little highter. As LQG can compensate the limitation of LQR that all state variables should be identified, LQG is more acceptable algorithm than LQR. Furthermore LQG shows a good performance both in the response reduction and the control force. Finally H₂ algorithm is employed to illustrate the importance of weighting filters considering the frequency characteristics of the response and the controller. It Is shown that the H₂ algorithm is found to be the most effective one for the response control with a little control force having a low frequency band.