Bridging a gap between Low and High Frequency measurements

INRiM’s primary AC-voltage standard is realized by means of a set of AC-DC Thermal Voltage Converters from DC range up to 1 MHz. Above this frequency, an AC-voltage standard has not been normally implemented because of low technical interest. Indeed, in that range, electromagnetic power, a quantity that is always well definable and measurable also at higher frequencies, becomes more interesting than the AC-voltage. Power standard is realized by means of microcalorimetric technique that, however, lacks in precision under 10 MHz. The result is a metrological gap from 1 MHz to 10 MHz, in which any electrical standard exists, at least at INRiM. To fill this gap a new measurement setup is now under development and characterization, which will allow performing AC-DC Transfer Difference measurement up to 100 MHz and realizing a low frequency power standard. In this paper a description of this new setup will be given together with a set of measurements.