A time-varying weights tuning method of the double EWMA controller
نویسندگان
چکیده
In recent years, the exponential-weighted-moving-average (EWMA) statistic based controllers are popular in semiconductor manufacturing. However, the single EWMA controller is not su3cient for compensating for the wear-out process. Thus, a double EWMA controller was proposed to enhance the capability for controlling the drifting process. In the literatures, in the solution of the double EWMA controller, only the “trade-o5” solution weights are used to tune the controller. However, it is a 7xed weight tuning method, and it is known that a time-varying weight will produce a superior performance over that of a 7xed one (J. Quality Technol. 29 (1997) 184). Therefore, this study aims to develop a heuristic time-varying weights tuning method for the double EWMA controller. The numerical results showed that the proposed time-varying tuning method possesses an improvement of least 10% over that of the 7xed weight scheme. ? 2004 Elsevier Ltd. All rights reserved.
منابع مشابه
Adaptive Simplified Model Predictive Control with Tuning Considerations
Model predictive controller is widely used in industrial plants. Uncertainty is one of the critical issues in real systems. In this paper, the direct adaptive Simplified Model Predictive Control (SMPC) is proposed for unknown or time varying plants with uncertainties. By estimating the plant step response in each sample, the controller is designed and the controller coefficients are directly ca...
متن کاملAdaptive Tuning of Model Predictive Control Parameters based on Analytical Results
In dealing with model predictive controllers (MPC), controller tuning is a key design step. Various tuning methods are proposed in the literature which can be categorized as heuristic, numerical and analytical methods. Among the available tuning methods, analytical approaches are more interesting and useful. This paper is based on a proposed analytical MPC tuning approach for plants can be appr...
متن کاملRobust Fuzzy Gain-Scheduled Control of the 3-Phase IPMSM
This article presents a fuzzy robust Mixed - Sensitivity Gain - Scheduled H controller based on the Loop -Shaping methodology for a class of MIMO uncertain nonlinear Time - Varying systems. In order to design this controller, the nonlinear parameter - dependent plant is first modeled as a set of linear subsystems by Takagi and Sugeno’s (T - S) fuzzy approach. Both Loop - Shaping methodology and...
متن کاملA Unified IMC based PI/PID Controller Tuning Approach for Time Delay Processes
This paper proposes a new PI/PID controller tuning method within filtered Smith predictor (FSP) configuration in order to deal with various types of time delay processes including stable, unstable and integrating delay dominant and slow dynamic processes. The proposed PI/PID controller is designed based on the IMC principle and is tuned using a new constraint and without requiring any approxima...
متن کاملAn ANOVA Based Analytical Dynamic Matrix Controller Tuning Procedure for FOPDT Models
Dynamic Matrix Control (DMC) is a widely used model predictive controller (MPC) in industrial plants. The successful implementation of DMC in practical applications requires a proper tuning of the controller. The available tuning procedures are mainly based on experience and empirical results. This paper develops an analytical tool for DMC tuning. It is based on the application of Analysis of V...
متن کامل