Rooftop Photovoltaic-Battery Systems to Mitigate Overvoltage and Under Voltage in a Residential Low Voltage Distribution System

¹ Green-Smart Energy Technology (G-SET) Research Group, Faculty of Engineering at Sriracha, Kasetsart University Sriracha Campus, Thailand
² Provincial Electricity Authority (PEA), Thailand

^* Corresponding author: umarin@eng.src.ku.ac.th

Abstract

High penetration of rooftop photovoltaic systems in a residential low voltage distribution system has to be controlled in order to maintain stable voltage condition. Energy storage systems, such as batteries, can be used to absorb excess energy of photovoltaic systems and to shave peak load during on-peak time. This paper proposes guiding principles for the incorporation of energy storage systems into a residential low voltage distribution system with high penetration of rooftop photovoltaic systems. Real residential distribution system circuits and all parameters from the Geographic Information System database of the Provincial Electricity Authority in Thailand were used for simulation analysis to study the application of energy storage systems for regulating voltage in a range of the nominal voltage by 10 %. Solar radiation data from the PVGIS were used. The voltage results were simulated by using the DIgSILENT Power Factory program. Based on the simulation, it was found that the overvoltage and under voltage protection and energy loss reduction could be achieved by (i) installing small battery systems in households and (ii) installing battery stations within the vicinity of the transformer or the weakest point of the circuit.