A study on dynamic behavior of coal-fired thermal power plant during significant system frequency rise after system separation

Power plants are increasingly located far from demand centers in Japan due to siting difficulties. As a result, these power plants are connected to a weak part of the network where severe contingencies could separate them from the main grid. This is a particular concern for coal-fired thermal power plants because of their larger footprints and environmental impact. Coal-fired thermal power plants, which have a relatively slow frequency response, can account for a majority of generation in an islanded system. In order to establish countermeasures for this problem and to maintain stable operation of the islanded system, the authors have developed models of coal-fired thermal power plants for system studies. This paper describes important findings obtained from analyses using the developed models, such as the necessity of modeling the power plant control system including main steam pressure dynamics which can limit the governor response to bring back frequency.