Small Signal Stability Analysis of Distribution Networks With Electric Springs

Abstract

This paper presents small signal stability analysis of distribution networks with electric springs (ESs) installed at the customer supply points. The focus is on ESs with reactive compensation only. Vector control of ES with reactive compensation is reported for the first time to ensure compatibility with the standard stability models of other components such as the interface inverter of distributed generators (DGs). A linearized state-space model of the distribution network with multiple ESs is developed which is extendible to include inverter-interfaced DGs, energy storage, active loads, etc. The impact of distance of an ES from the substation, proximity between adjacent ESs and the R/X ratio of the network on the small signal stability of the system is analyzed and compared against the case with equivalent DG inverters. The collective operation of ESs is validated through simulation study on a standard distribution network.