Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 112-119). Also available via the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 76-80). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 111-114). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 76-80). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 111-114). Also available on the Internet.

This thesis presents the development of a Hybrid Multilevel Switching Converter (HMSC) for Ring-Magnet Power Supplies (RMPS). The thesis includes the analysis, design and control of the proposed converter. It introduces multilevel switching converters to the field of ring-magnet power supplies. RMPS feed the electromagnets that produce the magnetic field required to energize and guide subatomic particles in a synchrotron. The accuracy and extreme precision of this magnetic field imposes stringent restrictions on the design and performance of the RMPS used. Study of conventional power supplies highlights the need for modern power supply solutions which can meet the specifications of RMPS. The complete frequency-domain analysis of the conventional resonant-type RMPS along with the Energy Make-up Unit (EMU) is presented. The resonant frequency drift is identified as the main factor in the design of the EMU. The analysis of the input filter network is presented for development of design criteria for input filter components. The principle advantages and disadvantages of the resonant-type RMPS are summarized before identifying multilevel converters as a viable option among switching converters for a non-resonant type of RMPS. The Hybrid Multilevel Switching Converter (HMSC) is proposed as a non-resonant type RMPS to overcome the disadvantages of the resonant-type RMPS. The operational features of the HMSC are explained and the simplification of the general HMSC configuration for positive output currents is identified. The steady-state analysis of the HMSC develops comprehensive design criteria for the device ratings and component stresses, including the methods for reducing the switching losses in the HMSC. Multilevel converters encounter voltage balancing problem among the DC-link capacitors. It is shown that the HMSC configuration is versatile in minimizing this problem. Harmonic spectrum of the output voltage of the HMSC is derived and the effect of number of output voltage levels in reducing the harmonic contents is established. A detailed survey of different current control techniques is presented to form the background for developing an effective current control algorithm for multilevel converters. A dead-beat current control strategy is chosen as an appropriate control technique to suit the needs of RMPS. The control scheme is extended to the control of multilevel converters in general. The control algorithm is developed to track a given arbitrary current reference signal for both single-variable and multi-variable systems. It is also shown that the output dead-beat control is a special case of the pole placement technique. The transient behaviour of the system has been studied and stability considerations of the system are examined. Extensive computer simulation studies have been performed using SABER to study the reference tracking nature of the proposed control scheme. The output current of the HMSC using the modified dead-beat control scheme is shown to follow a given arbitrary-reference with very small tracking error. The reference tracking nature has been simulated for a simple RL magnet load and a magnet load with LCR filter. Experimental results obtained from a laboratory prototype of the HMSC with an RL load, have been presented to substantiate the analytical results. Criteria for improvement in the reference tracking properties of the proposed system have been identified. / Graduate

No description available.

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.

Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: packaging; micro electro mechanical systems; MEMS; electronics; die warpage; die bow; encapsulant; encapsulate; electrochemical migration; corrosion; wirebonds. Includes bibliographical references (p. 94-99).

Thesis--Ph. D., University of Hong Kong, 1981.