Integrated Electric And Heat Optimal Schedule For Wind Consumption

Integrated energy system(IES)with multiple energy scheduling is an effective way to relieve the shortage of fossil energy,reduce environmental pollution,and improve energy efficiency.During winter,CHP units are the main sources for electrical systems and thermal systems,and then enhanced coupling between electric and heat.Due to the constraint of CHP units,the safety decreases during the valley load,which leads to reduce wind consumption.Therefore,research on the electric-heat optimal strategy is of great significance for the wind consumption,economic operation and energy efficiency.This paper studies the three aspects:"mathematical modeling and energy flow calculation method of electric-heat integrated energy system(EHIES)","optimal dispatch strategy of EHIES" and "real-time stochastic optimal energy flow(SOEF) calculation method for EHIES ",as follows:(1)Mathematical modeling and energy flow calculation methods for EHIES.Firstly,the structure,hydraulic and thermal characteristics of the thermal system are studied,and establish the hydraulic and thermal conditions functions.Establish the AC power flow method,and considers the coupling between the pumps and electric power.The equation of electric-heat energy flow is established,and solved by Newton Raphson(NR)method.IEEE 9 bus power grid and 45 bus thermal network is built as EHIES.It is proved that the proposed energy flow calculation method has good convergence.It provides the basic model for optimal dispatching,optimal energy flow,stochastic energy flow,probabilistic energy flow and risk assessment for EHIES.(2)Study the optimal dispatch strategy of EHIES.Firstly,three optimization targets of "energy consumption"," carbon emission" and "net loss" with constrains are established,and compare the scheduling strategy and indexes under different targets.Secondly,the electric heating(EH)is studied to participate in the optimal dispatching.And compare the influence of EHs with different capacity on scheduling strategy and indexes.The conclusion shows that the participation of EH in optimal dispatching is helpful to promote wind consumption.It provides a strong basis for the development and application of EHs.(3)Study real-time stochastic optimal energy flow calculation method for EHIES considering uncertainty.Firstly,the nonlinear optimization model of EHIES is established,and solved by original dual internal point method.Secondly,a stochastic energy flow calculation method based on clustering segmented linearization is proposed,and obtains probability distribution of state variables in time.Finally,the SOEF model of chance constraint is established,and solved based on optimal energy flow and stochastic energy flow.The results show that the SOEF method proposed in this paper has short calculation time.This method can calculate SOEF online,which is suitable for real-time dispatching of IES.