여자시스템과 동기발전기의 회전자 권선에 발생되는 과전압에 대한 보호회로 연구

The study of the protection circuit about overvoltage between excitation system and synchronous machines

In the case of synchronous machines, certain power system disturbances cause the induced rotor current to assume negative values when no static converter is present. A converter, however, prevents negative current from flowing, so that overvoltages occur. The overvoltages can be effectively limited as crowbar circuit using GTO. This newly proposed crowbar circuit with current limiting resistor absorbs energy when overvoltage comes from power system repeatedly and verified through experiment