Development of a Full-Scale Switched Reactor Fault Current Limiter for Distribution System

Abstract

The aerial distribution systems are vulnerable to extreme weather events induced by global warming and climate change. This vulnerability is evident in the growing frequency of faults caused by lightning strikes, direct contact with trees, and equipment failures. Also, wind and PV solar inject power variability into the system. Consequently, reclosers and transformers in the substations are experiencing overstress. In this context, this work presents the tests of a developed Solid-State Fault Current Limiter (SS-FCL) for installation in a medium voltage distribution substation. The developed equipment is composed of the solid-state switch with insulated-gate bipolar transistors (IGBTs), the maneuver and protection cubicle, and air core reactors. As it is equipment that involves software and hardware, it is necessary to mitigate errors in the coordination of the equipment for safe operation. In preparation for future testing in medium voltage, this research focuses first on troubleshooting the proposed solid-state system at reduced voltage (220 V). The following tests were carried out at the equipment manufacturer’s facilities: hardware tests (Intermittent test and Open switch test) and software tests or detection tests (Load switching test, single-phase and three-phase short-circuit test with and without downstream impedance). The goals of these tests are to analyze the performance of the computational algorithm in the detection of the short circuit and evaluate the supportability of the solid state switches in terms of voltage and current. These tests validate the equipment for the medium voltage test stage, which will be the next step of this work.