抄録
Combined cycle power plant which combines gas turbine and steam turbine can achieve high energy efficiency. Many combined cycle plants have been installed in the world. However, a large-scale blackout due to combined cycle chain trip-out occured in Malaysia. The cause of this chain trip is considered to be large drop of system frequency. From these backgrounds, there is a need to investigate stability of the combined cycle power plant for the frequency drop. Several dynamic models of combined cycle plant have been proposed. In our analysis, we use some of them and build a model for a single-shaft combined cycle plant. We execute numerical simulations to see how the combined cycle plant behaves when system frequency drops. The cause and the countermeasure of the combined cycle plant trip-out are explained.
