Testing the Effectiveness of Short-Circuit Current-Limiting Methods and Tools for Medium- and Low-Voltage Grids with Distributed Generation Facilities

Abstract

Large-scale integration of distributed generation (DG) and renewable energy facilities in medium-voltage (MV) and low-voltage (LV) distribution grids causes short-circuit currents (SCC) to rise. Technological redesign and organizational arrangements are needed to limit SCCs if the negative consequences are to be prevented. The paper discusses several types of wind farms to show how REFs can feed SCCs at damage site. It lists the factors that affect the magnitude of SCCs in MV and LV distribution grids in the context of energy efficiency and saving measures. The paper further presents an analytical review of known SCC limiting methods and tools (SCC limiters); it also analyzes the feasibility and effectiveness of implementing them in MV and LV grids. Choice of SCC limiting methods requires a feasibility study that draws upon the knowledge of distribution grids and their operating practices, and takes into consideration the capabilities of cutting-edge power electronics. Any attempt to limit SCCs should bring about more reliable electricity delivery. The paper enumerates measures to be taken for a comprehensive attempt to limit SCCs in MV and LV grids.