Analysis and Experimental Study in a Load Break Switch for a Smart Distribution System

Abstract

This paper presents an analysis and experimental study in a load break switch (LBS) using the smart microgrid of Khun Pae Village, Chiang Mai province, Thailand as the testbed location. An LBS can be automatically controlled by various signaling arrangements that are incorporated with a feeder remote terminal unit (FRTU), current transformer (CT), and voltage transformer (VT). Sometimes the metering CTs are used to detect fault currents. This can be saturated during a heavy fault. Thus, this paper proposed the simplified equivalent circuit to study the CT saturation in an LBS for a smart distribution system. The simulation was conducted by the DigSilent Power Factory and PSCAD simulation tools for verification of the proposed method. The results of the simulation software and experimental testing by using a current source transformer and on-site testing showed that there were slightly different secondary current values of these case studies. In this paper, the proposed analysis and experiment provided modeling and a measuring method of CT saturation testing in an LBS for a smart distribution system.