Date of Award
Master of Science (MS)
Electrical and Computer Engineering
Chung Seop Jeong, Ronald Brown
Disturbance accommodation control (DAC) is a method for designing a controller that minimizes the effects of disturbances of known waveform type, but with unknown arrival time, duration or magnitude. Systems that do not have a control term in the measurement equation pose a particular challenge for DAC design. A disturbance accommodation controller for these types of systems was previously developed by defining a pseudo-output consisting of the current output and previous control input terms with weighting coefficients.
The objective of the present work is to analyze the stability and performance of the discrete- time disturbance accommodation controller for systems without a feed forward term in the measurement equation. Three example systems each of first, second, and third order are used in this analysis. As a result of extensive graphical analyses, recommendations are made to enable designers to set appropriate limits on the range of the controller coefficients to ensure closed loop system stability and disturbance attenuation for a minimum cost. In addition, guidance is given for making an appropriate choice of sampling time to discretize continuous time systems to ensure closed loop system stability when using this type of DAC controller.