Abstract
AbstractAn active three-phase boost rectifier can easily be designed to achieve high power factor and low input current distortion. Hence, it has been widely applied in the industry, such as in rapid transit systems, arc furnaces, and as a dc-link of an ac/ac converter. Analyses and LC parameters design of the boost rectifier to fulfill proper performance requirements have been detailed in a previous thesis of a graduate of this lab. However, how to design a feedback controller to further improve the dynamic performance of the rectifier has not been finished yet.In view of these, this thesis is aimed at the design of high performance dynamic controller. First, by using the derived DC model of the rectifier, the author proposes a feedforward control by using the concept of conservation of energy to achieve a fast response due to a step load change. Then, by using the derived small signal model, the author adapts the fixed structure sliding mode control (FSSMC) of a previous dissertation of a graduate of this lab to achieve the robust control as well as eliminating the chattering phenomenon. Due to the change of the operating point of the rectifier, the originally designed FSSMC designed may not be able to maintain the nice performance for all loading conditions. Hence, the author further proposes an adaptive FSSMC to achieve better performance. Detailed theoretical basis is given in the context. Finally, a prototype is also constructed to verify the feasibility of the proposed control. The proposed controller is implemented fully digitally with a DSP to reduce hardware components, the volume and to simplify the maintenance problems.