Decoupled probabilistic feeder hosting capacity calculations using general polynomial chaos

Abstract

This paper introduces a decoupled method of calculating the PV hosting capacity of low voltage distribution system (LVDS) feeders for new solar photovoltaics (PV) installations. The hosting capacity calculation of LVDS is a multidimensional stochastic problem. A general polynomial chaos-based probabilistic power flow is used to solve this problem, as it allows for fast computation times without any compromise in accuracy. Two types of uncertainties exist in the hosting capacity calculation problem: planning level uncertainties such as size, location, type, and number of PV installations and operational uncertainties such as consumer load and PV generation. These two types of uncertainties are usually sampled together in probabilistic hosting capacity approaches. In this paper, a decoupled approach is presented where the impact of planning level scenarios on the probability of violation of operational limits is studied. The highest total PV among the planning scenarios inside the probabilistic bound of the operational limit is termed as the hosting capacity of the feeder. The results show that hosting capacity depends upon the planning uncertainties and operational variables, and decoupling them gives a more concise picture of the impact of different uncertainties.