Research on Photovoltaic Penetration Limits in Mid-Voltage Distribution Network Considering Output Uncertainty

The intermittence and fluctuation of output are the key factors when dealing with photovoltaic (PV) access capacity in distribution network planning. After taking the random characteristics of PV output and its relevance to load into account, the effective utilization of PV power generation capacity can be realized. This paper first adopts a Gaussian mixture model (GMM) to address the uncertainty issue of PV generation. Then, with consideration of the network structure and the temporal-spatial distribution characteristics of the load, a practical model for the evaluation of PV penetration limits is established. The effectiveness of the proposed model is validated through a case study, in which several factors that affect PV penetration are examined. This model is currently applied in an area in China for the determination of the penetration limits applied to existing and new solar farms.