Problems in switched-mode dc and ac power conversion
Several issues in the field of power electronics are discussed. Part I first reviews the method of state-space averaging to analyze steady state and small-signal behavior of switched-mode dc-to-dc converters. The approach is then generalized to encompass multiple inputs and a general form of feedback system. Since the method involves matrix manipulations it is well suited for computer computation. The Switching Converter Analysis Program was developed to implement the state-space averaging method, and requires computational power only of a small desktop computer. Part II extends the basic one-quadrant switching dc-to-dc converter to both current and voltage bidirectionality. The proposed push-pull power amplifier, being a four-quadrant converter, is capable of interfacing dc and ac ports. This special capability is then exploited to introduce a single-stage ac Uninterruptible Power Supply (UPS), which can process power from dc to ac or from ac to dc. Finally, Part III further generalizes the switching power amplifier to polyphase operation in such a way that a minimal number of power converters is required. Then, through a set of steps a new polyphase power amplifier is introduced. The idea is experimentally verified by a 1 hp variable-speed motor drive with regulated output voltages. The technique has many other advantages such as ease of paralleling, dc isolation, and voltage boost, etc.
- OSTI ID:
- 6896151
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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