In order to study the characteristics of the unit coupled with heat pump and to provide a basis for design of the control system

the mechanism model of the pulverizing system

steam and water system

turbine system and heating system were established. Moreover

based on the historical data of a 2×350 MW power unit under multiple operating conditions

the static parameters

dynamic parameters and uncertain functions of the proposed model were determined. In this model

the fuel command

feed water flow rate

opening of high profile valve

opening of lowpressure butterfly valve

inlet valve opening of the heater in heat network

and comprehensive position of heat pump steam regulating valve were considered as input parameters

and the power generation

main steam pressure

intermediate point temperature and intermediate pumping pressure were considered as output parameters. Moreover

the open-loop step disturbance test and closed-loop operation data verification were carried out. The results show that

under a wide range of variable load conditions

the relative error between the established mathematical model and the actual unit output is 0.37%～1.54%

indicating the model has high accuracy and good reproducibility. It can provide a theoretical basis for subsequent control system design.