Advancing the European metrology for wideband AC voltage

The 2025 EU guidance on developing “forward-looking electricity networks” highlighted the importance of further investment in electricity grids to replace outdated equipment and respond to emerging needs, such as innovative technologies and the smooth integration of renewables. During recent years, wideband measuring equipment for alternating current (AC) voltage have extended into frequencies in the 100 MHz range in areas such as healthcare, telecommunications and aerospace. As AC in the electricity grid changes direction and magnitude, averaging its effective power would give a zero value. Thus, it is converted to its DC equivalent using radiofrequency DC (RF-DC) digitisers. However, no National Metrology Institute (NMI) in Europe has RF-DC standards available at these frequencies to disseminate traceability and calibrate equipment.

Building on the work of TracePQM, SuperQuant and WAC, this project will bring together NMIs from around Europe to address this lack. It will develop novel RF-DC standards based on calorimetric thermal voltage converters at input voltages from 1 V up to 5 V and frequencies up to 100 MHz with low measurement uncertainties. New measurement setups will be established and validated by interlaboratory comparisons. An automated calibration system will also be developed for these voltages and frequencies and results disseminated to industry through a publicly available user guide and open software tool.

The new calibration services and metrological traceability established by Met4AC will support a wide range of modern advances such as high-precision electronic components, RF power meters, active medical implants, radio navigation, aeronautical communications, broadcasting and many more.