Sampling primary power standard from DC up to 9 kHz using commercial off-the-shelf components

In the framework of the EMPIR project MyRails, METAS developed a primary standard for electrical power using commercial off-the-shelf components. Custom software controls the sampling system and determines amplitude and phase of the different frequency components of voltage and current. The system operates from DC up to 9kHz, even with distorted signals. The power uncertainty is 15 µW/VA at power frequencies and increases to 1.8 mW/VA at 9kHz. The voltage and current channels can also be used independently to calibrate power quality instruments. Thanks to a time-stamping system, the measurement is synchronised to UTC.