Optimal Robust Control for a Class of Stochastic Model Errors

In this paper, we have investigated how the optimization methods can be used to deal with plant uncertainty. Firstly, a weighed sensitivity error function is presented by robust redesign. Then, by modifying the nominal controller to minimize the variance of the actual system performance from the desired performance over all frequency, we obtain a optimal robust controller design method for a class of stochastic model errors. Moreover, the results can be used to give a good prediction to the average tracking performance and control energy in practical control system designs