2027 Event Agenda

The integration of large exporting inverter-based distributed energy resources onto the distribution system introduces critical voltage regulation challenges. While IEEE 1547 establishes default smart inverter volt-var behaviors to mitigate grid impacts, these standard configurations are tailored to mitigate temporary voltage excursions. Large generators that may rely on non-unity power factor operation to control POI voltage can benefit from active Volt-VAR inverter controls, but the default IEEE 1547 volt-var controls should be tuned to suit the project and utility’s needs.

As Xcel Energy prepares for widespread adoption of active volt-var controls in inverter based DER on their distribution system, the utility is investigating the appropriate settings to optimize system performance and value to developers. This session  will summarize  the risks of implementing autonomously adjusting reference voltage (AAV) in volt-var controls for DER. Limitations of commonly deployed modeling tools to adequately adjust the reference voltage to evaluate inverter behavior when AAV is implemented will be explored. Drawing from these shortcomings, guiding principles for implementing static volt-var controls on large inverter-based systems will be presented, focusing on utility planning criteria. The most impactful scenarios occur when generators are exporting near peak levels of power, but low power export scenarios will be explored as edge cases where volt-var behavior mitigating low voltage conditions may be desired at the POI.