The multiple uncertainty impact of large-scale grid-connected PV system on available transfer capability assessment

Solar is a pollution-free green energy, and photovoltaic (PV) generation has been developing rapidly as people are paying increasing attention on energy and environmental issues. However, along with large-scale PV systems connected into the grid, the impact caused by its multiple uncertainties on regional transmission ability has become a serious problem, not only affects its effective consumption, but also presents challenges for system security and economy. Based on the credibility theory, this paper first built models of conventional generators and large-scale grid-connected PV system (LGPVS) according to their randomness and fuzziness features. Then random fuzzy simulation is proposed to be applied. A novel method of available transfer capability assessment which considers both randomness and fuzziness simultaneously is proposed, and the bootstrap method and the multi-core parallel computing technique are introduced to enhance the processing speed. The viability of the models and the method is verified by a simulation in the IEEE-30 bus system. Finally, the multiple uncertainty impact of LGPVS on regional available transfer capability is analyzed by applying the new models and method from aspects such as grid-connected size, access point selection and so on.