Research On Optimal Configuration Of Distributed Generation Based On Voltage Quality Analysis

Following the development of new energy and the increasing penetration of Distributed generation(DG),the influence of this new strategy on power quality grows to be more and more significant.Since a reasonable configuration of the DG scheme can effectively reduce access costs and improve power quality,thus the methods of optimization have attracted the attention of many scholars.This paper mainly study on the influence of DG grid-connection on the voltage quality and line loss of distribution network,and proposes a method for optimizing the configuration of DG grid-connection scheme.Firstly,through the theoretical analysis,It's concluded that the main factors that influence the voltage quality of distribution network are DG access location,access capacity,access number and node type,and analyzed the effect and law of its influence.Then introduces the basic working principle of photovoltaic power generation system,battery and super capacitor,and set up the models of photovoltaic power generation system,hybrid energy storage system through the DIg SILENT software,and a simple simulation to verify the correctness of the models.Then built the distribution network model to simulate the influence and law of the voltage amplitude,the harmonic voltage distortion rate and the line loss of the distribution network under the condition of different location,capacity,node type and multiple DG grid-connection scheme.Then analyze the effect of the measured PV output data on the voltage fluctuation of the node.It‘s found that the increasing of the PV output will cause the voltage deviation of the node is qualified while the voltage fluctuation exceeds limit.Therefore,it is necessary to connect the energy storage device to compensate the PV output,stabilize the voltage fluctuation to improve the DG access capacity,and verify the effectiveness of the energy storage device by simulation.Finally,Summarize the influence rule of DG access distribution network,found that DG access has a great influence on voltage quality and line power loss of distribution network.Considering that the hybrid energy storage system can well compensate for voltage fluctuations.Therefore,this paper studies the optimal configuration method of DG access based on voltage deviation and line power loss.By normalizing the reference index and setting up the fitness function,and find out the optimal access scheme in the case of different DG grid-connection scheme in the 18-nodes distribution network by genetic algorithm.