Research On Optimal Collocation Method Of Multi-type Distributed Generation Considering Uncertainties

With the increasing of environmental pollution and energy depletion,distributed power generation technology has been paid more and more attention by the governments of various countries.Distributed power supply access to distribution network has changed the power supply structure and system operation mode.It has great influence on relay protection measures,system power supply reliability and network loss,and the influence degree is closely related to the access position and configuration capacity of distributed power supply.If distributed power generation planning can improve the operation of the system,otherwise it may have a negative impact.It is of great theoretical value and practical significance to study the distribution network planning with distributed generation.This paper focuses on the multi-objective planning of distributed generation in distribution network.The main contents of this study are as follows:(1)The power flow of distribution network considering the uncertain factors of source load side is stochastic.Firstly,the probability model of wind turbine,photovoltaic unit output force and load fluctuation is established,and then combined with the relevant knowledge of mathematical statistics,The power flow of distribution network is calculated by semi-invariant and Gram-Charlier series expansion.Finally,the simulation calculation of IEEE33 node distribution network system is carried out.(2)Universal gravitation algorithm is an excellent heuristic intelligent optimization algorithm proposed in recent years.It has the advantages of fast searching speed and high convergence precision.In order to make the algorithm have the ability to solve multi-objective optimization problems.In this paper,a multi-objective universal gravity algorithm is proposed to solve the proposed model by introducing the non-dominated sorting operations,elite reservation operations and crowding distance operations in the fast non-dominated genetic algorithm into the algorithm calculation process.(3)By analyzing the influence of different load nodes on the active power loss of the system,a method is proposed to determine the location of distributed power supply based on the sensitivity of active power loss.Considering the influence of various uncertain factors on the source load side,a multi-objective configuration model is established based on the chance constraint programming method,which considers the pollutant gas emissions,the voltage deviation index and the network loss synthetically.A multi-objective universal gravity algorithm with embedded probabilistic power flow is used to solve the model to determine the optimal configuration capacity.The PG&E69 node distribution system is taken as a simulation example to verify the validity and rationality of the algorithm and model.