Real-Time Energy Consumption Analysis in Load-Cycling Processes of Coal-Fired Power Unit

In order to eliminate the fluctuating impact of renewable energy on the power grid, coal-fired power units undertake the increasing peak-shaving tasks, but the energy consumption of coal-fired units in transient process is difficult to evaluate. Based on the calculation method of the energy consumption on the steady state operating condition and the operating characteristics during transient process, from the two parts of the boiler and steam turbine, considering the boiler heat storage in the transient process and the influence of the deviations in turbine steam thermodynamic parameters, with some simplifications to meet engineering application requirements, finally a more general energy consumption analysis model is established. With the model the real-time energy consumption calculation of coal-fired units can be carried out under the whole operating condition. The energy consumption analysis model is applied to a 660MW ultra-supercritical unit, and the calculated energy consumption results are consistent with the measured coal consumption trend. Furthermore, the energy consumption characteristics of the model are compared with that of the simulation model. The data of the two models agree well, and the difference between the calculated values of the standard coal consumption rate is less than 1%, which proves the reliability of the energy consumption analysis model.