Real-World Implementation of Advanced PV Curtailment and Reactive Power Control Using Non-Smart PV Inverter: A Case Study

Solar Energy has experienced the fastest increase of installation around the globe among all the Renewable Energy Sources in recent years. But grid overvoltage and power quality issues, expensive transmission line upgrades, line congestion etc. are standing in the way of larger penetration of solar in the existing century-old distribution grid. The existing grid infrastructure was not designed to regulate the overvoltage issues caused by the intermittent nature of the excess penetration of solar energy. Smart inverters can go a long way in mitigating the overvoltage and undervoltage issues by providing reactive power support, but deploying these inverters require large-scale, expensive system upgradation. This paper deals with this problem in a cost-effective way by implementing real-time active power curtailment and reactive power variation on three already existing, non-smart PV inverters at a real-world microgrid testbed, and validating through real-time data monitoring. The outcomes of the presented control systems are not only in compliance with the new `Rule 21' for smart inverters, UL 1741SA but also saves the expenditure of a new smart inverter and existing line upgrades.