Semester

Spring

Date of Graduation

2001

Document Type

Dissertation

Degree Type

PhD

College

Statler College of Engineering and Mineral Resources

Department

Lane Department of Computer Science and Electrical Engineering

Committee Chair

Parviz Famouri.

Abstract

With today's trend for distributed generation and the need for alternative and renewable energy sources, self-excited induction and synchronous reluctance generators have attracted more attention for wind, tidal and hydro power generation applications. Compared to synchronous and DC generators, they have the advantages: they are brushless, they are robust, they do not need DC excitation and they are relatively low cost.;Compared with SEIG, the self-excited reluctance generator (SERG) not only has the advantages of simplicity and ruggedness, but can also have enhanced steady-state characteristics and high efficiency over a wide range of operation. Moreover, its output frequency is determined only by the prime mover speed, rather than by both the load and the prime mover speed as in an induction generator, so SERG can be easily integrated with power electronic devices to implement a control scheme.;Most of the current analyses deal with three-phase reluctance generators, but insufficient attention has been paid to single-phase self-excited reluctance generators (SPSERG). Their unbalanced loads make their analysis more difficult. This research is motivated by the fact that SPSERG provides a good alternative to single-phase induction generators used in stand-alone generation applications. A general methodology is suggested for transient response prediction and steady state performance analysis for the SPSERG type of electric machine.;To establish a design environment, finite element method is an effective tool, which can be integrated in machine modeling to obtain good performance prediction. In this work, an off-line FEM approach is proposed to obtain the saturation characteristics for state space simulation. During the process, transformation between instantaneous inductance and average inductance is investigated. Off-line FEM + SS approach is proved to be a simple and economic method and can fit the experimental results in good accuracy.;Moreover, a steady state model has to be built to reveal the parametric dependence and provide good design guidance. However, because of the unbalanced load and nonlinear feature of the machine, existing models are not suitable for analysis. In this dissertation, a novel inductance-oriented steady state model based on the harmonic balance technique is introduced. The idea is that starting from the inductance determination under certain load, the fluxes can be attained by a nonlinear relationship, after that, the machine variables can be solved according to the fluxes. Comparison between simulation and experiment validates this approach.

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