Control Method Of High Robustness And Dynamic Response Based On H∞ And V~2 Control

With the rapid development of new generation electrical equipment and microprocessors, its power supply needs higher performance standards, including fast dynamic response, simple control circuit and better robust stability. To meet this demand, this project has designed BUCK converter of high robustness and dynamic response based on H∞ and V~2 control, satisfying the requirements of system performance characteristics by designing control loop.Aiming to improve the system dynamic response, the control loop of the main circuit adopts V~2 control to increase the dynamic response speed of the DC power supply. This dissertation analyzes the operating characteristics of BUCK converter based on V~2 control, and the feature of V~2 control is studied according to its small signal model. V~2 control technique is compared with voltage mode control and current mode control technique in frequency domain, as a result, th e dynamic response of V~2 control is better than the other two methods.Due to the fast dynamic response of V~2 control BUCK converter, it brings bad anti-interference ability, to solve the problem, design ing compensator applying H∞ control theory is proposed. This dissertation introduces the design process of BUCK converter based on H∞ control theory, obtaining that the system of H∞ control has advantages of good robustness and anti-interference ability by analyzing its frequency domain.In order to obtain stable power supply which has fast response and good anti-interference ability, H∞ control theory is introduced in V~2 control loop to modify control loop in this project, and the original controlled system is modeled and analyzed. Then the weighting functions are selected according to the characteristics of system, H∞ controller is designed by MATLAB robust toolbox.The performance characteristics of BUCK converter based on H∞ and V~2 control is verified in frequency and time domain simulation, the system has fast dynamic response, better anti-inference ability and high robust stability. When input voltage and load are changed suddenly, the system remains stable and better dynamic response. Therefore, the experiment verifies the feasibility of BUCK converter based on H∞ and V~2 control, meeting the standards of high robustness and fast dynamic response in switching power supply.