PV power ramp events probability modeling and assessment in multiple time scales

Photovoltaic (PV) power fluctuations and PV rate events have significant influence on the operation of the grid. In order to analyze PV ramp events in short time scales, the generalized Gaussian mixture model (GGMM) of PV power ramp rate is set up. By comparison with different models under different time scales and weather types, the results show that 3 order GGMM performs best to describe the probability distribution of PV ramp rate under short time scales. Then, based on the proposed model of PV ramp rate, the probability of PV ramp events is assessed in short time scales. Finally, applying the swinging door algorithm, modified score function and defined label vector and so on, PV ramp events are identified under different weather types and it is concluded that ramp duration, ramp speed and ramp magnitude in a long time scales are all in power-law distribution. The distribution of three kinds of indicators under the sunny days and other days is different. © 2019, Editorial Board of Acta Energiae Solaris Sinica. All right reserved.