分布式光伏对配电网谐波特性的影响研究

Study of the Impact of Distributed PV on Distribution Network Harmonic Characteristic

分析了分布式光伏的谐波特性、并网点负荷阻抗、电容器组投切等对配电网谐波特性的影响。通过在PSCAD/EMTDC中搭建的分布式光伏与配电网络模型,进一步验证了理论分析的正确性。仿真结果表明:在仅考虑谐波问题时,分布式光伏更适于在PCC点并网;此外并网点的负荷阻抗过高将不利于分布式光伏接入;电容器组投切引起的谐波阻抗变化对节点电压畸变率影响明显。研究结果对降低分布式光伏引起的谐波问题具有一定参考价值。

In order to investigate the distribute network harmonic characteristic of distribufed PV, this paperanalyzed different scenarios, including distributed PV harmonic characteristics, load impedance, capacitor bankswitching, and multiple access situation and so on. Based on building distributed photovohaic power generation systemand the radiation power distribution network model in PSCAD/EMTDC software, through multiple sets of numericalexample it verifies the correctness of above theoretical analysis. The simulation results show that, when onlyconsidering harmonic problem,distributed photovohaic（PV） is more suitable for the PCC access to grid;in addition,high load impedance of access point will go against distributed photovohaic access; capacitor banks switching thatcausing harmonic impedance change has obvious influence on the node voltage distortion rate. The study results has acertain guiding significance for reducing harmonic problems caused by the distributed photovohaic.