Technique for stability enhancement of microgrids during unsymmetrical disturbances using battery connected by single‐phase converters

Abstract

This study proposes a technique for the enhancement of the stability of microgrids during unsymmetrical temporary faults in the distribution network. In order to enhance the transient stability and the quality of voltage in the microgrid during different disturbances caused by faults in the distribution network, this study proposes a concept with a centralised battery energy storage system. The battery is connected to the network through single-phase converter units which are to be implemented in every phase so that they can inject independently both the active and reactive power in certain phases. The proposed technique enhances the transient stability of microgrids and provides symmetrical operating conditions for consumers and generators in it during all temporary symmetrical and unsymmetrical faults in the distribution network. An innovative concept has been proposed for managing the balance of active and reactive power that uses, as control variables, magnitude and voltage phase angle at the point of connection of the microgrid to the distribution system. The proposed concept and technique have been tested on the IEEE 33 BUS system with additional sources. The dynamic simulations of disturbances and the verification of the proposed technique have been performed in DIgSILENT PowerFactory software.

Battery energy storage systems (BESSs) and the economy-dynamics of microgrids: Review, analysis, and classification for standardization of BESSs applications

“…Currently, the researchers are studying the transient characteristics of the grid-forming and grid-feeding VSCs to ensure stable FRT schemes [197], [198]. Nevertheless, after establishing the suitable models, BESSs would be beneficial to improve the system performance, e.g., by compensating asymmetrical faults components [199]. The critical point in the transient study is the SoC estimation and DC-link performance [68] which demand more investigation for large transients.…”

Battery Energy Storage Systems (BESSs) and the Economy-Dynamics of Microgrids: Review, Analysis, and Classification for Standardization of BESSs Applications

“…Currently, the researchers are studying the transient characteristics of the grid forming and grid feeding VSCs to ensure safe FRT schemes [35], [191]. Nevertheless, after establishing the suitable models, BESSs would be beneficial to improve the system performance, e.g., by compensating asymmetrical faults components [192]. The critical point in the transient study is the SoC estimation and DC-link performance [68] that demand more investigation for large transients.…”

Evaluation of Passive Islanding Detection Methods for Line to Ground Unsymmetrical Fault in Three Phase Microgrid Systems: Microgrid Islanding Detection Method

“…The under/over voltage protection (UVP/OVP) and under/over frequency protection (UFP/OFP) methods are very simple and incorporated in all grid connected inverters and relays connected with DG system protection. In these methods, the voltage and frequency are both constantly monitored at the PCC [1,8], where:…”