Applied Energy, Vol.230, 1126-1139, 2018
Effects of the operation regulation modes of district heating system on an integrated heat and power dispatch system for wind power integration
The rational and effective operation regulation mode of a district heating system plays a significant role in heating feasibility, security, and energy savings of an integrate heat and power dispatch system for integrating fluctuating wind power. In this study, a new integrated heat and power dispatch model considering the thermal inertia of an indirect connection district heating system (including the district heating network and buildings) were proposed, in which complete hydraulic and dynamic thermal model of the indirect connection district heating system was first proposed and the function of the integration method was further improved for simulating the dynamic temperature distribution of a district heating network under variable flow conditions. On this basis, the operation regulation modes of the district heating system were respectively applied into the integrated heat and power dispatch model to analyse and compare their effects on an integrated heat and power dispatch system for wind power integration in terms of heating feasibility, security, and energy saving, in which a real indirect connection district heating system in Jilin Province was used. Results demonstrate that the proposed model can truly utilize the thermal inertia of an indirect connection district heating system to increase the wind power integration by regulating the operation of the heat source based on the optimal temperature and flow rate at the heat source and the predicted indoor temperature. Case studies show that applying the "variable temperature-variable flow control mode" to the integrated heat and power system is more economical, which is 0.9% less than the "variable temperature control mode" by reducing the pump power consumption and 2.9% less than the "centralized control with flow varied by steps mode" by promoting wind power integration. Therefore, the proposed integrated heat and power dispatch model can be applied to truly utilize the thermal inertia of an indirect connection district heating system for wind power integration and select the best operation regulation mode of the district heating system for wind power integration in an integrated heat and power dispatch system.
Keywords:Integrated heat and power dispatch;District heating system;Wind power integration;Thermal inertia;Operation regulation mode