K.Y. Shen, J.C. Gu, and T.H. Chen
Ring type distribution systems, pilot relaying systems, dependability, security
This paper proposes a novel protection scheme for ring type distribution systems. Using an intelligent electronic device (IED) equipped with a dedicated communication channel and programmable logic controller (PLC) makes this configuration more feasible. Not only the main protections are presented, but also the backup protections are well introduced in detail whenever the system configuration is ring or radial. This investigation discusses pilot relaying systems, mainly including the permissive overreaching transfer trip (POTT), the directional comparison blocking (DCB) and direct transfer trip (DTT) schemes. Meanwhile, the hierarchical protection scheme of ring type distribution system is adopted in the primary feeder system. This work demonstrates that the proposed protection scheme is extremely well designed so that both the numbers and the durations of interruptions caused by the faults can be minimized. Especially, the most significant advantage of this system is that the service is not interrupted when a fault occurs on the feeder. Based on the above-mentioned novel protection scheme, a trade-off is also made between the dependability and the security of protection system, particularly considering the communication channel conditions. The evaluations of the performances of ring type distribution systems are also described.
Important Links:
Go Back
