Accurate Modeling and Assessing the Time-Domain Operation of Protection Devices in Electrical Distribution Networks

Presence of distributed generation (DG) may cause some disadvantages in the operation of electrical distribution systems. The mal-operation and inconsistency of protection devices are some of the most common issues of DG presence in the distribution grids. In the other words, the mal-operation of protection devices can induce the Electric Energy Not Supplied (EENS) of the grid which cause a reduction in reliability of power system. Thus, accurate modeling of the protection devices e.g., auto-reclosers, sectionalizer, over-current relays, and fuses; and assessing their dynamic operations by time domain simulating can help the grids owners and operators to reduce the EENS. In this study, accurate models for protection devices are presented and, also their time-domain operations are simulated in the DIgSILENT PowerFactory platform by using a part of distribution network of Yazd city, Iran as a case study. Furthermore, a novel approach based on protection devices time-current curves (TCCs) and two pairs of short-circuit currents is presented for protection coordination.

Keywords:

Distributed Generation , Distribution Feeders , Protection Coordination , Protection Devices Modeling , Power System Transients