Performance of utility interconnected photovoltaic inverters operating beyond typical modes of operation

Abstract

The high penetration of utility interconnected photovoltaic (PV) inverters can affect the utility at the point of common coupling. Today's utility interconnection standards are evolving to allow voltage and frequency support, and voltage and frequency ride-through capability. With multi-MW-sized PV plants and multitudes of small commercial and residential systems coming online each year, the interconnection standards are allowing distributed energy resource equipment to provide reactive power to supplement existing voltage-regulating devices and ride-through voltage and frequency anomalies. These new interconnection requirements, coupled with the high dc-to-ac ratios, are becoming more common with declining PV module costs and are changing the modes of operation for utility-interconnected PV systems. This report investigates the effects these modes of operation have on the inverter performance, array utilization, and power quality while focusing on conversion efficiency.