Output Power Limit and Excitation Method Effect Comparison in Trial Fully Superconducting Generator

Abstract

A study on efficient excitation system would be important to enhance potentials of superconducting AC generators. Based on such a concept, we have fabricated an experimental machine for actually generating the electricity with a brushless exciter system which consists of a superconducting dynamo or “magnetic flux pump”. The fully superconducting generator has also been studied, in which both of armature and field windings are made of superconductors.
We made tests for actual power generation and estimated its static electrical characteristics, resulting in 20kVA class available with not only the conventional excitation system, but also the novel brushless excitation system.
The paper presents a comparison of elctrical characteristics in using the brushless excitation method and the external DC current source through brush-slipring system. And the results suggest that the brushless superconducting generator could yield higher output as compared with the conventional excitation.