Grid Voltage Control Using Hybrid Control Technologies during Changing Weather Conditions

Residential customers with roof-top smart inverter Photovoltaics (PV) are gradually increasing the penetration levels of Distributed Energy Resources (DER) within secondary systems. Distribution planning and operations engineers wouldn't want to compromise the system integrity and reliability due to high DER penetration. Smart inverters have the capability of maintaining the distribution system integrity, if it is optimally configured with the existing distribution system control device(s). The use case that will be explained in this paper describes the results of combining traditional distribution system control devices such as line voltage regulators, switched capacitors, Integrated Volt-Var Control (IVVC) with varying smart inverter control functionalities to regulate feeder voltages and reduce line regulator tap operations. Changing weather conditions exacerbates the dynamic nature of the distribution system. Hence, varying load profiles, load shapes and solar conditions is needed to clearly analyze secondary systems. A time-series analysis was performed using EPRI developed OpenDSS and OpenDSS-PM tools to determine the overall impact to the distribution feeder as solar PV and load vary independently. The aim of this project was to utilize hybrid control technologies to check the technical impacts of changing the settings of roof top PV with smart inverters connected to secondary systems. Additionally, unconventional metrics to better estimate the overall performance of the distribution power system is introduced in this paper.