Model-free controller tuning based on frequency response data

In this paper, we propose a direct tuning method of linear multivariable controllers based on frequency response measurements. Prior to the controller tuning, the plant is stimulated by some appropriate excitation signals, and the frequency response measurements are obtained by DFTs of the input-output data. Then a linearly parameterized controller is obtained by minimizing a frequency-shaped model reference control criterion at selected frequency points in the frequency-domain. The control performance seems to be transparent, owing to the visualized frequency-domain data. The performance of the proposed method is shown through extensive simulation studies.