The Great Britain system has undergone many changes over the past few years. Specifically, a significant amount of wind generation has been added to the system. As a result, the short circuit levels at the transmission substations have reduced. In addition, a number of conventional generation stations will be retired in future years. This will also significantly impact the short circuit levels at certain substation locations.
The purpose of the proposed study is to investigate the impact of the low short circuit levels on the performance of existing protection relays. The settings of certain types of relays may be more impacted than others. This study aims to identify if generator, transformer and line protection will be impacted due to system changes and identify necessary mitigation measures. The impact of power electronic devices including HVDC on protection performance will also be considered across the analysis of Generator, Transformer and Transmission Line protection.
An area of the network around Mark Hill (high levels of power electronic devices) is tentatively identified as a potential area to be considered in this pilot study. The investigation will be based on simulations on PSCAD/EMTDC platform as well as selected Hardware in the Loop (HIL) testing of relays on the RTDS platform. The National HVDC Centre will collaborate with a team of experts from Manitoba Hydro International (MHI) to meet the objectives of this timely investigation.