Indonesian Journal of Electrical Engineering and Computer Science Vol. 19, No. 3, September 2020, pp. 1259~1266 ISSN: 2502-4752, DOI: 10.11591/ijeecs.v19.i3.pp1259-1266  1259 Journal homepage: http://ijeecs.iaescore.com Mitigation of overvoltage due to high penetration of solar photovoltaics using smart inverters volt/var control Dilini Almeida 1 , Jagadeesh Pasupuleti 2 , Janaka Ekanayake 3 , Eshan Karunarathne 4 1,2,4 Institute of Sustainable Energy, Universiti Tenaga Nasional (UNITEN), Malaysia 3 Department of Electrical and Electronic Engineering, University of Peradeniya, Sri Lanka Article Info ABSTRACT Article history: Received Feb 1, 2020 Revised Mar 22, 2020 Accepted Apr 13, 2020 The modern photovoltaic (PV) inverters are embedded with smart control capabilities such as Volt/Var and Volt/Watt functions to mitigate overvoltage issues. The Volt/Var control has gained a significant attention in regulating grid voltage through reactive power compensation. However, the reactive power capability of a PV inverter is limited during peak irradiance and could be improved by curtailing the active power generation and by oversizing the PV inverter. This paper analyzes the performance of Volt/Var function of smart PV inverters in mitigating overvoltage issues due to high PV integration and thus increasing the hosting capacity of low voltage distribution networks (LVDNs). The study is conducted on a real Malaysian LVDN considering two different Volt/Var set points under different PV penetration levels. Results demonstrate that the oversized smart PV inverter could enhance the Volt/Var functionality by increasing its reactive power capability than a typical smart PV inverter. Further it reveals that adaptation of sensitive Volt/Var set points with shorter deadbands increase the PV hosting capacity of LVDNs. Keywords: High PV penetration LV distribution network Reactive power capability Smart PV inverter Volt/var control Copyright © 2020 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: Dilini Almeida, Institute of Sustainable Energy, Universiti Tenaga Nasional (UNITEN), Jalan IKRAM-UNITEN, 43000 Kajang, Selangor, Malaysia. Email: dilinialmeida2@gmail.com 1. INTRODUCTION Over recent years, solar power generation has shown a rapid growth compared to the other Distributed Energy Resources (DERs). The declining cost of PV modules and incentives set up in many countries around the world have aided the growth of solar PV to emerge as one of the most widely adopted DER in LVDNs. However, the increased influx of solar PV penetration leads to new technical challenges [1, 2] to the Distribution Network Operators (DNO), who are responsible in maintaining the power quality of LVDNs. Voltage rise, voltage flicker and unbalances, thermal overloads, and higher levels of harmonics are some of the technical issues caused due to high integration of solar PV to LVDNs. Voltage rise has been identified as one of the worst consequences of high solar PV penetration which could substantially limit the number of PV systems connecting to the LVDN. The peak generation and low demand conditions could significantly increase the reverse power flow resulting voltage rise at the end of the feeder [3, 4]. As can be seen in literature, a reasonable number of studies have been published addressing the voltage rise issues and feasible solutions for mitigation. Grid reinforcement, integration of On-Load Tap Changers (OLTC) [5-7], Line Voltage Regulators (LVR), Static VAR Compensators (SVC), Static Synchronous Compensators (STATCOM) [8], capacitor banks [9] and large-scale Battery Energy Storage Systems (BESS) [10, 11] are some of the voltage regulation strategies implemented by DNOs. However, these approaches lead to costly investments and require a