Research On The Effects Of Distributed Photovoltaic (pv) Grid-connected Power Generation For Power Distribution Network

In the dual pressures of environment and energy, distributed PV systems penetrate into the distribution system. With electric power customer demand for power quality and safety of power supply reliability, a series of status quo.which is produced by distributed photovoltaic (pv) grid power generation system for the user side’s power quality,is getting more and more people’s attention.Distributed photovoltaic (pv) grid power generation system is of great significance for the stable operation of distribution network, and its grid-connected position and injection capacity has a direct impact on distribution network’s network loss and voltage distribution operation. The paper studies distributed photovoltaic power generation, composition’s principle, classification, model and structure.And from the voltage stability, power flow and power quality, network losses, system reliability,the thesis analyzes the affection of distributed PV and power generation systems for distribution network.This paper studies and summarizes particle swarm optimization, forward and backward substitution algorithm, puts forward a improved particle swarm algorithm,and realizes simulation and analysis for it. The improved algorithm for line voltage increasing, decreasing network loss, improving the system stability has important significance.Meanwhile, under the premise of forward and backward substitution algorithm,the paper presents a new theory based on the smallest losses algorithm, so that it can be applied to any multi-branch distribution network load.lt studies the regular pattern of distribution network node voltage changes as variation of distributed photovoltaic power generation system’s network location and injection capacity, and realizing reactive power compensation in a distributed grid-connected PV systems and network simultaneously. The improved algorithm is applied to IEEE33 simulation and it achieves flow calculation in the node distribution network power.When the single PV and PV group are connecting network, reactive power compensation is realizing, so the distribution of each node’s voltage can reach above 10.17kV and 10.2kV respectively.Then, after PV group grid-connected network and realizing reactive power compensation,the active and reactive power losses reduce to 1/3 of the original distribution network loss. This result verifies the improved minimum network loss theory based on the backward sweep algorithm,by which to adjust distributed photovoltaic system interconnection and to achieve reactive power compensation, it improves stable operation of the distribution network significantly.