Active phase control to enhance distance relay in converter-interfaced renewable energy systems

For the distance protection applied in converter-interfaced renewable energy systems, various AC fault ride-through strategies of converter-interfaced sources will cause a large phase difference between the operating current of the distance relay and the fault current, resulting in the mal-operation of the distance relay. To overcome this issue, this paper proposes an active phase control for the converter-interfaced renewable energy systems to enhance the reliability of the distance relay. This control scheme firstly calculates the phase difference between operating current and fault current by only using local measurements. Then, the phase difference is eliminated via phase angle adjustment. To verify the effectiveness of the proposed control scheme. The performance of the proposed method is tested in a radial three-terminal system and the IEEE 14-bus system in PSCAD/EMTDC