Research On Multi-time Scale Scheduling Strategy Of Electro-thermal System Considering Thermal Inertia

Nowadays it has become difficult to rely solely on the power system to consume the wind power that is developing more and more rapidly,while the heat network,as an energy system,has a large energy storage space itself.Therefore,to study the power system to achieve the problem of wind power consumption,we need to consider the heating system at the same time,so that the heating system and the power system become a whole,thus increasing the system’s ability to cut peaks and fill valleys.It can do as much as possible to absorb the constantly fluctuating wind energy,increase the utilization rate of energy,and break the bottleneck of wind power development.In order to solve the abandoned wind phenomenon in winter,this paper starts from both heat network and power grid,and studies the delayed characteristics of input and output temperature changes of heat pipe network,cogeneration units and heat load,and establishes the heat system energy transfer model;Studies the coordinated optimization problem of thermal inertia and demand-side response of pipe network and building,and establishes the demand-side response model considering thermal inertia;studies the electric-thermal system scheduling problem based on the operating cost and environmental cost of the electric-thermal system The problem of electric-thermal system scheduling based on the optimization of electric-thermal system operation cost and environmental cost is studied,and a multi-time scale electric-thermal system scheduling model is established.The research contents of this paper are as follows.（1）Analyze the characteristics of the source-net-load link in the heating system,explore the heat source output,and establish a mathematical model of the heat source.To study the fluid hydrology and heat transfer of heat transfer pipes,heating buildings,heat exchangers and radiators,and to establish thermal models containing inertia for each internal thermal system.The heat storage capacity of the building and the pipe network itself is studied,and the thermal inertia model is used to achieve load leveling and to provide help for wind power consumption and to lay the foundation for subsequent research.（2）Considering the regulating characteristics of electric load,in response to the fluctuation and uncertainty of wind power output,the demand-side response dispatching model is established through certain dispatching mechanism by constantly changing the tariff as well as reaching agreement with users in advance,so as to study the demand-side response dispatching model considering thermal inertia on the basis of the thermal energy transmission model containing inertia,relax the thermoelectric coupling of combined heat and power units（CHP units）,and enhance the flexibility of the electric-thermal system.（3）Considering the different effects of different time scales on the wind power output prediction and demand-side responsiveness,the multi-time scale scheduling strategy of day-ahead-intra-day-real-time is established by setting different scheduling time periods.Taking into account the thermal inertia of heating buildings and heating networks,and considering the relevant thermal constraints,a multi-timescale dispatching model of electricity-heat system considering thermal inertia is established to better realize wind power consumption from both the power system and the heat system.The effectiveness of the model to consume wind power is verified by simulation calculations.