Comparative Analysis of Anti-Islanding Requirements and Test Procedures in the United States and Japan

Existing standards require that DGs disconnect from the grid in a short period of time in order to coordinate with protection systems, avoid poor power quality that can cause damage to connected load, and for safety reasons. The goal is to prevent the unintentional formation of an electrical island. Based on industry experience, today's active anti-islanding algorithms are very effective. Consideration of scenarios with high penetration photovoltaic (PV) has renewed interest in anti-islanding performance in certain cases involving multiple inverters of different types, or inverters that incorporate voltage and frequency tolerance or control voltage. This paper describes the results of anti-islanding testing and analysis conducted by Sandia in collaboration with Kandenko Co. Ltd. (Kandenko) and Japan Electrical Safety & Environment Technological Laboratories (JET), to evaluate the performance of existing and new anti-islanding technologies in the multi-inverter case, and to compare anti-islanding requirements and test procedures applicable in the United States and Japan.