Multi-Time Scale Dispatching Strategy For Integrated Energy System Considering Flexible Electric And Thermal Load

Promoting wind power consumption of combined heat and power system is the intersection of promoting clean energy consumption in the internal part and cultivating emerging business in the external part,both of ubiquitous network of things construction.It is also a typical application of multi-energy interconnection.How to alleviate high wind abandonment during the heating season is also a realistic problem to be solved in “the Three Norths” area of China.This dissertation starts from the wind power consumption mechanism of flexible load and fully calls both electric and thermal load,which aims to promote the friendly integration of renewable energy such as wind power and ensure the low-carbon stable operation of the combined heat and power system.Firstly the thermoelectric coupling characteristic of heating units is analyzed and the common strategies of eliminating wind abandonment is summarized.Then give the consumption mechanism of flexible load.The first part also compares those strategies and gets the superiority of flexible load in mitigating wind-heat conflicts and promoting wind power integration.The model of price-based load and incentive-based load are analyzed and introduced into the power generation dispatching as the demand side interactive resource.And according to this,a dispatching strategy with flexible electric load of combined heat and power system is proposed.Then we can obtain the optimized electric load curve.Simulation results show that the use of economic levers can effectively guide users to adjust the power consumption mode,smooth the electric load curve,and both the peak shaving effect and economic benefits are good.However,this method is limited by the responsive ability.For better wind power consumption,it is fine to cooperate with other methods.Heat load resource is considered and the models of heating load and industrial heat load are established respectively.Flexible heat load resource is introduced into power generation scheduling by relaxing heat power real-time balance constraint.And according to this,a dispatching strategy with flexible heat load of combined heat and power system is proposed.Then we can obtain the optimized heat load curve.Simulation results show that using the thermal dynamics of the building can soften the limit of heat demand on heat sources.It can also ease wind-heat conflicts during night without additional investment costs,with good economic returns.However,this method is limited by the users' thermal comfort and has limited adjustment capability.Considering the differences in wind power prediction accuracy and in incentivebased load response ability at different time scales,based on the optimized electric and thermal load curves obtained in the previous simulation,a multi-time scale dispatching model for integrated energy system with flexible electric and thermal load is established,with the aim of minimizing the total operating cost and environmental cost of the system.Simulation results show that with the combination of sources and load under the three time scales of “day-ahead,intra-day,real-time”,various flexible load can be fully invoked to relieve the fluctuation of renewable energy and reduce wind curtailment.The multi-time scale dispatching strategy of integrated energy system considering flexible electric and thermal load proposed in this dissertation has guiding significance for low-carbon and safe operation of combined heat and power system.