Primary frequency control performance assessment for thermal power plants under deep peak shaving

Abstract

Primary frequency control (PFC) has become increasingly important for the stable operation of power systems, and a very limited number of renewable energy sources are available to provide frequency stabilization services. The coal-fired power generations still need to provide fine PFC services. It is crucial to assess the capability of the thermal power unit under a dynamic changing process. It is important for energy saving to realize the performance prediction and optimal control of heat exchange systems considering dynamic characteristics. Based on the theory of heat current theory, the transient heat current model is established, and the corresponding comprehensive constraint equation is derived to reflect the heat transfer process and heat storage value in the boiler. In a case study of a 600 MW supercritical power plant, the capacities of PFC response are quantified for the first time. The new model of the boiler validates energy increment accurately during the deep peak shaving process with an accuracy of 97.56%.