Performance of Smart Revenue Meters Under Bidirectional Active Energy Flows in Energy Communities

Abstract

Bidirectional active energy flows are expected to increase in electrical distribution systems (DSs) worldwide as a result of future incentives to exchange energy within local energy communities. Distributed generation (e.g., solar rooftop photovoltaic systems) in combination with full-cycle pulsewidth regulated loads (e.g., thermal appliances or some energy diverters), battery storage systems, or regenerative loads will result in periodic changes in the energy flow direction. If the regulation periods are close to the aggregation time window of smart revenue meters (RMs), the deviation from the correct readings of export and import registers might be significant. Subsequently, economic transactions that rely on readings from RMs, especially in community grids, might fail. The article presents an overview of the active power and energy metrics that are either already being implemented in static RMs or derived from other applications of active power measurement. A parametric analysis and an experimental case-study demonstrated quantitatively that different metrics and different influencing factors/conditions can lead to large deviations in the readings of RMs in community grids, causing significant technical and financial consequences. Finally, a new testing procedure capable of verifying the susceptibility of RMs to these quickly changing bidirectional energy flows is proposed and experimentally demonstrated with the goal of including it in future updates of the relevant standards.Bidirectional active energy flows are expected to increase in electrical distribution systems (DSs) worldwide as a result of future incentives to exchange energy within local energy communities. Distributed generation (e.g., solar rooftop photovoltaic systems) in combination with full-cycle pulsewidth regulated loads (e.g., thermal appliances or some energy diverters), battery storage systems, or regenerative loads will result in periodic changes in the energy flow direction. If the regulation periods are close to the aggregation time window of smart revenue meters (RMs), the deviation from the correct readings of export and import registers might be significant. Subsequently, economic transactions that rely on readings from RMs, especially in community grids, might fail. The article presents an overview of the active power and energy metrics that are either already being implemented in static RMs or derived from other applications of active power measurement. A parametric analysis and an experimental case-study demonstrated quantitatively that different metrics and different influencing factors/conditions can lead to large deviations in the readings of RMs in community grids, causing significant technical and financial consequences. Finally, a new testing procedure capable of verifying the susceptibility of RMs to these quickly changing bidirectional energy flows is proposed and experimentally demonstrated with the goal of including it in future updates of the relevant standards.