An automated impedance estimation method in low-voltage distribution network for coordinated voltage regulation

Abstract

Internode line impedance values are essential information for achieving coordinated voltage regulation with distributed energy devices. However, in a low-voltage distribution system, these values are difficult to acquire, especially when the devices are installed in an ad hoc manner by individual users. This paper proposes a novel method for automated impedance estimation based on practically available parameters at the terminal nodes. The distributed energy devices measure and transmit the terminal parameters to a host device. Then, the host device estimates the line impedances based on its impedance model and the collected parameters. For practical implementation, the proposed method is built under several assumptions. For example, it is assumed that the phases of terminal voltages are not synchronized owing to communication latency. Instead, only the magnitude value is incorporated during the impedance estimation. The proposed method is verified via a simulation that assumes a realistic environment.