Overvoltage Correction in Active Distribution Grids using Smart Inverters and Load Control: A Comparison

Abstract

Active distribution systems, which include significant amounts of distributed energy resources (DERs), are often more reliable and resilient. Paradoxically, these systems are also prone to power quality problems such as harmonics, under-voltages and overvoltages due to reverse power flows and the intermittent nature of most DERs. A major solution to most of these challenges is the use of smart inverters. However, for electric utilities and cooperatives operating demand response (DR) programs, flexible loads could also be used to address some of these power quality problems in addition to peak load reduction purposes. This paper compares the usage of smart inverters and flexible loads for specifically addressing overvoltages in a distribution grid due to the integration of solar photovoltaic (PV) resources. The overvoltage phenomenon is simulated using a modified IEEE 13-bus test system within the OpenDSS simulation tool. The use of flexible loads and smart inverters for correcting the observed overvoltages is simulated and analyzed. Finally, the results obtained from both approaches are compared from both performance and cost perspectives.