Use of Voltage Detection Systems as transducer – Practical return of experience

Abstract

Voltage Detection Systems are more and more used for additional applications besides their historical use for voltage presence indication for the DNO staff. Equipped with a dedicated system which allows to access and measure the voltage at the middle of the capacitive divider inside it, they could be used as transducers for medium voltage measurements.Based on preliminary investigations on the accuracy of VDS for voltage measurements and the potential use cases, two concrete applications have been tested at length and yielded mixed results. The use of VDS as a transducer for PMU measurements in MV cabinets is unfortunately not a valid use case due to the accuracy limit of the phase angle measurements, which is an order of magnitude higher than the observed magnitudes. Their use for directional relays phase angle measurements proved however successful and was validated in various test set-ups. This is due to much larger phase angle shifts expected in case of a fault, the limited accuracy of the phase angle measurements thus being high enough in this case.