Modeling of Boiler-turbine Coordinated Control System in Coal-fired Power Plants for Power System Unified Dynamic Simulation of Transient, Medium-term and Long-term Stabilities

Boiler-turbine coordinated control systems(CCS) plays an important role in satisfying the load demand of power system and ensuring the stable operation of coal-fired generating plants.Based on the analysis of the principle and control modes of CCS,a new CCS model was proposed,which could be applied to power system electro-mechanical transient,medium-term and long-term dynamics simulation.By setting appropriate parameters in model flexibly,the model can be used to simulate several kinds of control modes of CCS,such as,boiler following,turbine following,coordinated control,direct energy balance control,etc.This model was developed in the power system unified dynamic simulation program.Two simulation cases show the influence of different mode of CCS on the mechanical power output of generating units and the effect of CCS model on the power system simulation related to power-frequency dynamics.