Photovoltaic Solar Farms Operating in VAR Mode: A Review

Abstract

The PV solar inverter plays a vital role in solar farms for electrical power generation at distribution end. By generating active power, such at lower distributed end results like voltage rise issues and voltage fluctuations which affect power quality standards. Increasing penetration level of distributed generation sources connected to the power system cause increasing reverse power flow when demand is not adequate, which raises the voltage level at point of common coupling at grid connection. For regulation of voltage at such PCC, FACTs devices based on power electronic converter are in practice. During night time or some cloudy days, when PV system is unable to generate active power, photovoltaic inverters are utilized for reactive power support to the grid. Here, various control techniques for utilization of PV inverter operating in VAR mode are reviewed. When active power is not available by PV inverter, various methodologies for reactive power control, voltage regulation and control of load reactive power have been mentioned by useful literature survey. The role of inverter as FACTs device for reactive power compensation is elaborated comprehensively.

Keywords: PV solar farms, FACTs, PV-STATCOM, PCC voltage regulation, VAR compensation