ASSESSMENT AND ALLEVIATION OF VOLTAGE SAG-INDUCED ECONOMIC LOSSES IN MODERN INDUSTRIAL DISTRIBUTION SYSTEM

Abstract

Modern Industrial Distribution networks consist of Solar PV and power electronics-based loads, such as variable frequency drives (VFD). PV and VFD could be used to ride through voltage sags and prevent costly load interruption. Hence, this thesis first proposes a method to assess annual economic loss for an industrial network consisting of PV and dynamic loads due to probable voltage sag events. Secondly, the proposed method is extended to identify PV inverter sizing and placement to alleviate the economic impact of voltage sags. Finally, the impact of load type change to VFD on the cost of load loss and modification of VFD DC link capacitor to reduce this cost is studied. The PV and VFD installation-based strategies show reasonable reductions in voltage-sag-induced economic losses compared to the conventional STATCOM-based method. Network designers can use them to decide the most effective voltage-sag mitigation strategy for their networks.