Reasons behind this project
Power system restoration plans are designed by Transmission System Operators (TSO) to identify procedures to recover the electrical network after a blackout. Traditionally, restoration cells rely on generators equipped with synchronous or asynchronous machines, while ballast loads are either static loads or pumps. With the high shares of converter-interfaced distributed energy resources that are being installed (and will be installed) in electrical grids, traditional restoration plans might turn out not to be suitable nor optimal to reliably energize the system.
In particular, it is of interest to investigate the potential benefits of converter-interfaced technologies such as large-scale Battery Energy Storage Systems (BESS) connected at the transmission system level. Indeed, BESS four-quadrant capability makes them an ideal candidate for providing various ancillary services, including system restoration. The advanced, fast controllability of modern power converters can undoubtedly be exploited by TSOs for the provision of multiple grid support services.
Extensive literature contributions and technological advancements have proven the capability of static technologies in forming a grid in case of absence of an external primary energy supply system. Such features have been proven to be also suitable to support the operation in case of a system restoration.
Restoration project aims at exploring the potential benefits of BESS within the actuation of power system restoration plans relying on generic and detailed validation models of electrical grids.
More specifically, the project will:
- Analyse the impact and benefits of converter-interfaced controllable components on network restoration strategies. Specific focus on BESS with four-quadrant control and operation.
- Investigate current practices by other TSOs.
- Define control approaches (focus on standard control modes).
- give technical requirements of BESS and resource coordination.
- Identify optimal design features for the size and location of BESS at the high voltage level.
Restoration is a common project, explored in 2023 by Swissgrid, RWTH Aachen, Uni. Ljubljana and RTE.
Picture credits: RTE