Copula Theory-Based Typical Scenario Generation of Photovoltaic Joint Output for Power Systems

The uncertainty of photovoltaic output threatens the stability of power systems. However, there is still a lack of research on the photovoltaic joint output and its temporal difference. To this end, a method for generating typical scenario set of photovoltaic joint output based on the Copula function is presented. Firstly, the scenario analysis to generate a large number of photovoltaic output scenarios is presented to address the uncertainty problem of photovoltaic power generation. After that, multiple joint output models of photovoltaic power plants based on Copula theory are built for 24 time periods separately, taking the temporal variation of photovoltaic output into account. And the goodness-of-fit analysis is presented to assess various types of Copula models. Then, Copula models and K-means algorithm are utilized to realize scenario sampling and typical scenario set generation. Finally, case studies on the historical photovoltaic output data in a regional grid are conducted, to verify the advantage of the proposed model, and it is shown that the proposed method can be applied to power system optimization models.