A new relay for interconnected distribution in the UK-design and field experience

Abstract

The design of a new microprocessor based multifunctional relay for use on interconnected 33 kV circuits is described. The relay uses sequence component principles and rented low grade VF communication. It was needed urgently because rented metallic communication circuits, which are in widespread use, are being withdrawn in the UK. The relay development is unusual because of its measurement methods and because it can derive polarising voltage from existing 1 1 kV VTs. The time scales required were such that development, field trials and installation phases overlapped. The field experience is described.

Research about impact of DGs in distribution networks

“…So, because of the high-impedance value of the reactor [6], in line fault, distributed power provided by the significant reduction in short-circuit current, to the point of failure and reduce the arc extinguished distributed power generating units detected the negative sequence current, to ensure the healthy operation of generating units.…”