Excitation Control System Design of Superconducting Generator with High Response Excitation in Consideration of SMES Effect for Improving Stability

Abstract – Superconducting generator (SCG) with superconducting field winding has many advantages such as small size, light weight, high generation efficiency. In particular, the property of low synchronous reactances, which is not realized in conventional generators, is able to improve power system stability. In addition, transient stability can be improved by effect of high response excitation of self-excited SCG which enables the rapid change of field current and in turn of excitation power. The field winding connected to the power system through converter is considered as a superconducting magnetic energy storage (SMES); hence, the effect is called “SMES effect”. In this paper, excitation control system for SCG with high response excitation considering SMES effect is proposed for stability improvement by employing eigenvalue sensitivity. The control performance of the proposed exictation control system is examined in IEEJ East 10-machine and West 10-machine systems. It is made clear that the SMES effect of SCG is utilized effectively and results in both transient and dynamic stabiilty improvement. However, the performance depends on the locations of SCGs and fault contingencies