Simulation and experimental results have previously shown that commercially available (ac connected) distance protection relays can provide sufficiently fast-acting backup protection for dc-side faults on medium-voltage dc (MVDC) links. This paper demonstrates, through real-time hardware-in-the-loop simulation, how an R-X coordinate-based setting approach can improve the stability of the solution via a series of fault studies.
To validate the proposed improved protection strategy, the protection algorithm is implemented on a low-cost computing platform to demonstrate the minimal computation effort required to realise the proposed solution. The algorithm could be readily applied to existing commercially available distance protection relays via updates to relay configuration software and relay firmware.
L. Hunter, Q. Hong, C. Booth, 2020 page