A New Formulation of Distribution Network Reconfiguration for Reducing the Voltage Volatility Induced by Distributed Generation

Volatile voltage profiles in distribution systems caused by the fluctuating nature of renewable distributed generation (DG) are attracting growing concern. In this paper, we develop a new formulation of network reconfiguration to mitigate voltage volatility. It provides new insights into the voltage regulation problem in distribution systems with high renewable penetration, which is commonly addressed by power electronic controllers. From the linear DistFlow equations, we first propose a novel index that measures the voltage volatility of each bus in the system. This index is a function of distribution network parameters that characterizes the role of network structure in voltage volatility. Then, we formulate a new reconfiguration model that minimizes the network loss and restricts the voltage volatility indices with the coordination of switched capacitor banks. A Benders decomposition-based approach is designed to solve the problem using mixed-integer quadratic programming. The simulations on the IEEE 69-bus system show that the reconfiguration scheme is able to: first, minimize network loss when DG outputs are as predicted; and second, significantly reduce the risk of voltage violations when DG outputs deviate from the prediction. The proposed formulation unleashes the distinctive power of network reconfiguration in reducing voltage volatility, by which the cost of power electronic controllers can be saved.