Two-stage Optimal Dispatching Method For Distribution Network With Photovoltaic-gas Turbine

In the context of the current power reform and energy crisis,the large-scale utilization of distributed generation(DG)has become the trend of international energy development.Directly connecting DG to the distribution network for local consumption has become the main source of renewable energy.However,due to the randomness and volatility of DG,as its penetration rate in the distribution network gradually increases,the cost of traditional adjustment methods to ensure the stable operation of the system by adjusting the system network structure increases and becomes more and more passive However,the high requirements of the centralized dispatching method in the existing research on the communication facilities and the computing power of the central controller in the distribution network are difficult to implement in the current distribution network environment.Therefore,relying on the active distribution network technology,this paper studies the two-stage fully distributed coordinated and optimized dispatch strategy of the DG distribution network from the perspective of ensuring the safe and stable operation of the distribution network.Aiming at the problem that the source-load output is difficult to match in the distribution network with a high proport ion of distributed power sources,this paper considers the introduction of gas generators into the distribution network and establishes a photovoltaic-gas turbine distributed dispatch model.The strategy is divided into two stages,active power dispatch an d reactive power dispatch.In the active power dispatching stage,the article extracts and clusters the characteristics of the actual area load and photovoltaic output historical data to obtain the output scenario of the high condensing load and the actual time sequence characteristics of the photovoltaic,and realizes the processing of DG and load uncertainty;combined with low voltage The current situation of the development of the distribution network with unsound communication conditions and weak comput ing capacity.The article introduces distributed control algorithms to equate gas generators as intelligent bodies,extracts their marginal costs as variables,and dispatches gas turbines through consistent coordination and optimization.Output,minimize t he amount of active power imbalance in the network while ensuring the optimal dispatch cost,and improve the economics of active power dispatch in the distribution network;in the simulation example which is built in this thesis,the dispatch strategy proposed in this thesis is proved to be valid.Considering that there are still voltage instability problems in the distribution network due to the variable power flow caused by DG access,after utilizing and analyzing the reactive power margin that the DG co ntained in this network still remain,and based on the implementation of distributed active power optimal scheduling,give electrical distance a new definition whis is on the basis of sensitivity,and on the new definition of electrical distance base,the distributed strategy requies network to be partitioned to control the voltage,a two-stage optimal dispatching model for the distribution network of photovoltaic-gas turbine coordinated operation is constructed,and a two-stage optimal dispatching strategy of the network which carries DG inside is further proposed.The simulation is executed on the distribution network model of the classic IEEE33 node,and is compared with the traditional centralized optimization scheduling method based on the intelligent algorithm under ideal conditions.The simulation and analysis of the calculation examples verify that the two-stage fully distributed optimal scheduling strategy proposed in this paper is effective in realizing the active power balance in the network,main taining the stability of the node voltage and reducing the line loss under the condition that only simple communication exists between individual gas generators.It is effective,and at the same time verifies its absolute superiority in scheduling time,an d it is suitable for the development status of my country’s distribution network under the background of high DG penetration.