| In recent years,there are more and more penetration of distributed generations(DGs)in traditional distribution network,which makes traditional distribution network transform into active distribution network(ADN).With the rapid development of electrothermal coupling elements,the interconnection between ADN and district heating network(DHN)gradually becomes tighter.The application of DGs and electrothermal coupling components is an effective way to promote the utilization of renewable energy,which needs to be incentivized by price signals.Therefore,each energy network needs a suitable market clearing strategy to promote the circulation of each energy market,to achieve the optimal clearing result of each energy market.On this basis,for the bidirectional power flow between the transmission network and the distribution network,the study of the district electricity-heat integrated energy market provides an opportunity for DGs and electrothermal coupling elements to coordinate energy pricing and trading with transmission system operator(TSO).Based on the above research background,this paper mainly completes the following research work:1)This paper introduces the research status quo of integrated energy market,and gives the optimal power flow model of distribution network and district heating network.This paper expounds the relationship between the market clearing model and optimal power flow model,and according to the characteristics of electrothermal coupling components(this paper refers to the CHP unit and electric boiler),to build the structure of district electricity-heat integrated energy market,reveals the coupling and interconnection relationship between the energy market at the district level.2)Considering the Stackelberg game relationship between the distribution system operator(DSO)and TSO,a bi-level optimization model for distribution market clearing and distribution location marginal prices(DLMPs)calculation is proposed.Firstly,the Stackelberg game relationship between DSO and TSO is determined,and the market clearing framework of the cooperation between transmission and distribution network considering the Stackelberg game is further established.Secondly,according to the proposed market clearing framework,a bi-level optimization model is established,in which the upper level is the distribution market clearing and DLMPs calculation model,and the lower level is the transmission market clearing and LMPs calculation model.Then,the proposed bi-level market clearing model is transformed into a singlelevel model using the Karush–Kuhn–Tucker(KKT)condition.Finally,a coupling system composed of a PJM 5-bus transmission system and an IEEE 33-node distribution system is taken as an example to verify the effectiveness of the proposed model.The proposed model can reduce DLMPs and improve the economic benefits of the distribution network and transmission network,and the interaction between DSO and TSO is shown.3)According to the structural characteristics of the district electricity-heat integrated energy system,and based on the Stackelberg game relationship of transmission and distribution network analyzed above,a bi-level market clearing model of district electricity-heat integrated energy market considering the cooperation between transmission and distribution is established.Firstly,according to the characteristics of the electrothermal coupling element,the district electricity-heat integrated energy market clearing model is established,and the model is determined as the upper level.The lower level is the transmission market clearing model.Then,the proposed model is transformed into a mathematical programming model with equilibrium constraints(MPEC)by using primal-dual counterpart conditions.In order to facilitate the solution,the MPEC model is linearized,and the equilibrium point of DSO and TSO is obtained.A testing system of IEEE 30-bus transmission network with a district electricity-heat integrated energy system comprised of a33-node ADN and a 32-node DHN is used to verify the rationality of the proposed model.Using the proposed model can reduce DLMPs and improve the economy of ADN and DHN,and a solution to the imprecise relaxation of second order cone is proposed. |
