Research On Dispatching Mode Of Cogeneration Units With Heat Storage Device

With large-scale new energy accesses to the power grid,the problem of new energy curtailment caused by “wind-heat conflict” in the “Three North Region” has become increasingly serious.The reason for this is that the rigid constraint of the combined heat and power unit “heat-setting” limits the space for new energy.Studies have shown that this limit can be uncoupled by configuring a heat storage tank with a CHP unit to increase the flexibility of the unit operation.However,how to dispatch a CHP unit with a heat storage device becomes a problem needed be solved.This article focuses on the problem and conducts research in two ways: How to dispatch the CHP unit with heat storage device by itself in the small network system? How does a CHP unit with heat storage device in a public network system respond to electricity price incentives? In response to the above issues,the main work and conclusions of this paper are as follows:In order to solve the problem that how to dispatch the CHP unit by itself,this paper proposes three kinds of dispatching modes based on the different positions of the thermal power plant in the system: When the thermal power plant is located on the power supply side and is in close contact with the new energy power,this paper puts forward the dispatching model of joint operation of the CHP unit and new energy power;When the thermal power plant is located on the user side and is in close contact with the load,this paper puts forward the dispatching mode that the CHP unit aims at load peak shaving;When the thermal power plant needs to take into account the coordination of the load and the new energy power,this paper puts forward the dispatching model that the CHP unit follow the “equivalent load” to operate.In order to evaluate the proposed dispatching model and compare it with the traditional dispatching model,this paper establishes a correlation model for each scheduling model,and analyzes the theory and examples.The example analysis shows that the three dispatching modes proposed in this paper can respectively reduce the fluctuations of new energy power,load and "equivalent load";Compared with the traditional dispatching model,the coal consumption and abandonment rate of the system can be reduced,and the economy can be improved.Finally,this paper develops a complete set of processes for the autonomous dispatching of thermal power plants.To solve the problem of how to respond to electricity price incentives for CHP with heat storage devices,this paper formulate the operating strategies for the CHP unit and the heat storage tank based on time-of-use price and peaking-assisted service incentives respectively with the goal of maximizing the profit of CHP units.Using the electricity price subsidy obtained by the unit as an indicator,the time-shared price and peaking assistance service incentives were compared with the benchmark price incentives.The example analysis shows that the institution of time-of-use price and peaking auxiliary services can not only stimulate the enthusiasm of CHP unit peaking,but also can enable the thermal power unit to obtain higher profits compared to the benchmark price system.The research results of this paper have certain reference value for the scheduling operation of thermal power unit with heat storage device.