超速応励磁形超電導発電機の励磁系詳細モデルを用いた励磁制御による電力系統安定性向上効果に関する検討

摘要

SCG (Superconducting Generator) has a superconducting field winding, which leads to many advantages such as small size, high generation efficiency, low impedance, and so on, and be considered as one of the candidates to meet the needs of high stability and high efficiency in the future power system networks. SCG with high response excitation is especially expected to be able to enhance the transient stability of power system by its SMES (Superconducting Magnetic Energy System) effect. The SMES effect of SCG is recognized that its behaviors are dominated by the structures and controls of its excitation system. For this reason, in order to verify exactly how the SMES effect of SCG influences on the power system stability, the electrical circuits of SCG high response excitation are modeled in detail for conducting digital simulation, and its influence on excitation voltage and active power output of SCG are discussed as well. The simulation results with a typical one machine - infinite bus power system model shows that the SMES effect can be certainly obtained when its exciting power is supplied from SCG terminal bus and may considerably lead to an improvement of power system transient stability.%1．はじめに増大し続ける電力需要に対処するため，発電設備や送電設備の新増設が進められているが，近年，発電所や送電線の用地確保難，電力系統安定度余裕の低下などの諸問題が顕在化しつつあり，電源の大容量化や遠隔地設置への対応，電力系統の更なる高安定化，高密度化，および高効率化が要求されている。これらの要求にこたえる技術の一つとして超電導技術の電力応用があり，発電機，電力貯蔵装置，限流器，電力ケーブルなどについて，現在，国内外で積極的に研究開発が進められている（1）（2）。