Protection schemes form part of the most fundamental components of any power system. They ensure that when faults occur on networks, the effect of the fault is seen only briefly by the wider system and its connections, isolating the faulted infrastructure or generator from the network, hence allowing the healthy elements to continue to operate. By doing so, risks to personnel and risks of damage to the infrastructure of the AC power system are reduced. This article explains how declining system strength presents challenges to confidence over future protection relay operation – and highlights how the HVDC Centre is helping to address these challenges. Click here to read the full briefing note or Download  file below.