The impact of distributed photovoltaic on the distributed network

With the increasing of photovoltaic (PV) penetration in the distribution network recent year, the impact of PV is more and more obvious. This paper first study the mechanism of PV impact on distribution network through the equivalent circuit of grid-tied PV system. Then we establish a typical distributed network model which contain PV generator, the voltage profile is researched from the perspective of PV capacity, power factor, generator location and line parameter. In the end, we propose several ways to enhance the ability of absorbing more distributed PV from the perspective of reducing the effect of PV on the voltage at PCC (point of common coupling). With the continually consumption of fossil energy and increasingly focus on energy security and environmental issues, renewable and clean Energy has raised concern in electrical sector. For now, the research of PV is widely carried out in many countries, the impact of distributed PV generator on the distributed network is mainly generalized in the following two aspects. on one hand, distributed network become complex multi-terminal networks which is different from traditional radial networks, on the other hand, PV belongs to intermittent sources which have significant time-varying characteristics and is susceptible to weather. The varying of power flow will contribute to the change of the node voltage distribution, volatility and time-varying characteristics also cause the change of outputting power, both of them will contribute to limit exceeding in the worst-case scenarios. The paper analyze the mechanism of the impact of PV generator on the distribution network, then establish a typical distribution network model to study the influence of PV in the perspective of voltage. Several factors such as capacity, power factor of PV, network parameters and the integrated way are discussed using the typical model. At the end, the paper put forward several measures to raise the capacity of distributed PV in the point of weakening impact of PV.