Development and application of an advanced switched reluctance generator drive

摘要

This dissertation contains the results of research conducted on the design andcontrol characterization of a Switched Reluctance Generator (SRG) for maximum outputpower. The SRG is an attractive solution to the increasing worldwide demand ofelectrical energy. It is low cost with a rugged structure, operates with high efficiency overa wide speed range, and is fault tolerant. In many applications, size and weight are themain criteria in selecting the generator. Hence, in design and control of the generator,system designers always strive for increasing power density, or in other words,maximizing the output power for a given size. Despite the extensive research on themotoring operation of the Switched Reluctance Machine, only a few publications haveinvestigated the generating mode of operation of this machine. Results and algorithmsfrom this research can be referenced for better utilizing the SRG in many applications.As the first stage to output power maximization, design parameters and controlvariables affecting the average output power of the SRG are identified through asystematic approach. The optimal values for maximizing the output power are foundthrough an analytical approach and iterative simulations. The results are then verifiedexperimentally. After finding the optimal values for control variables, a controller is designed.This controller is model dependent. If the model used for design is not accurate or themachine parameters are deviated from the designed values, the machine will not generatethe maximum output power. Therefore, a self-tuning algorithm, based on a local searchmethod, is proposed and experimentally tested. It works effectively and does not needextra hardware or rigorous calculations.The attempts to benefit from the SRG may look tantalizing, but it poses achallenge as well. Output power maximization can lead to an oversized SRG converterand its output filter, which will reduce the overall power density of the motor drive. Thelast piece of this dissertation analyzes the effect of a commutation algorithm on theoutput filter, reducing its size with active control of phase currents, and proposing a novelcontrol algorithm that was investigated through experiments over all of the speed range.