Explicit Relations between Electrical Transient Characteristics and Structure-parameters of Superconducting Generators under Sudden Short-circuit Faults

Abstract

Superconducting generators (SCGs) have many advantages as compared with conventional ones, and practical use is expected. Before practical use, it is necessary and important to have a good grasp of the electrical characteristics of SCG under short-circuit conditions. And it is desirable that, relations between characteristics and structure-parameters of generators are explicitly and simply expressed. We obtained transient characteristics of armature current and field current for SCG by use of mathematical electro-magnetic field analyses, and studied relations between characteristics and structure-parameters of machines. In this paper, the method of solution is explained for the sudden line-to-neutral short-circuits, while only the results are quoted for the line-to-line, and the doubleline-to-neutral short-circuits. Comparisons between analytical and experimental, using 20kVA SCG, results were also studied. Consequently, the parameters that dominate the amplitude of transient current were clarified. Besides that, close agreements between analytical and experimental results were obtained.