Portland State University. Department of Electrical Engineering
Date of Award
Master of Science (M.S.) in Electrical Engineering
1 online resource (2, vi, 58 p.)
Electric current converters, Semiconductor switches
The frequency response analysis of switched networks plays a very important part in designing various kinds of power converter circuits. In this thesis two frequency response techniques for analyzing switching power converters are discussed. One method provides a mathematical description which treats the converter as a periodic time varying system. A linearized small signal model is subsequently derived. The major part of the thesis concentrates on this accurate exact small-signal technique. The derivation involves state space representation and the use of the time varying transfer function. A Fourier analysis is performed to show the relationship between the frequency response of the network and the time varying transfer function. The obtained expressions are in closed form. The method has proven to be exact. The complexity of this technique is overcome by automating its derivation in conjunction with a circuit simulator. An alternative method, relying only on a sampled-data representation, is also derived, which provides a less complicated algorithm. However the accuracy of this method suffers, particularly at high frequencies. The accuracy of the exact small-signal technique is verified by experimentation.
Niu, Weihe, "Exact Modeling of Time-Interval-Modulated Switched Networks" (1993). Dissertations and Theses. Paper 4622.