Nonparametric preventive/corrective voltage stability enhancement of active distribution systems with integrated electric vehicles charging facilities

Abstract

The increasing penetration of electric vehicles (EVs) and renewable energy resources (RESs) have raised concerns about the voltage instability in distribution power systems. Thus, some probabilistic algorithms are needed by decision-makers to quickly yet accurately evaluate the voltage stability margin in smart distribution systems. This paper proposes a nonparametric preventive control to mitigate the risk of voltage instability in the active distribution systems consisting of EVs and RESs. First, a framework is developed to evaluate EVs' degree of participation in preventive control by estimating potential achievable power capacity (PAPC). To estimate the probability density function (PDF) of the system voltage stability margin, Bernstein density estimator (BDE) is utilized due to its capability to handle the boundary effect. Finally, a preventive/corrective control model based on the model predictive control (MPC) is developed considering the dynamic behavior of EVs and RESs. The capability of the proposed algorithm is tested on the modified IEEE 33-node system.