Measurement Setup for a DC Power Reference for Electricity Meter Calibration

Abstract

In recent years, low-voltage DC (LVDC) grids allow for a more efficient and sustainable integration of renewable energy sources. In order to facilitate such transition, though, several normative and metrological aspects need to be addressed. In particular, the calibration and type-testing of DC power and energy meters shall rely on traceable reference systems, capable of assessing the meters' performance in nominal and distorted conditions. This represents a preliminary yet crucial step towards the actual deployment of LVDC grids in modern power systems. In this paper, we present the design of a DC power reference system and discuss the main implementation challenges. In this regard, we identify the most significant uncertainty sources and propose ad hoc measurement procedures and hardware solutions to minimize their contributions.

Traceability for AC Ripple Over DC Current

“…Nevertheless there is a considerable lack of metrological references for this kind of measurement. Considering current measurements, reference transducers are always calibrated for DC or AC, never for both [14]. To the best authors' knowledge, the CMCs (Calibration and Measurement Capabilities) of the NMIs (National Metrology Institutes) are related to DC-only or AC-only quantities.…”

Power Quality Measurements in a Low-Voltage DC Microgrid in an Open Parking Garage

“…The need for measurements to underpin new definitions of DC PQ is addressed in the European metrology project "20NRM03 DC Grids" [14] by measuring and analyzing the distortions occurring in LV DC microgrids and developing reference systems for the calibration of DC power meters [15] and DC PQ analyzers, and for testing DC equipment such as DC electricity meters in the presence of well-defined distortions [16]. The first measurement campaigns have been executed already in LV DC microgrids in Malaga Smart City in Spain, with micro wind turbines and PV panels at a voltage level of 48 V [17], the Green Village in Delft, the Netherlands, with LED streetlights and PV panels and operated at 350 V [18], and three different public EV charging stations in Germany [19].…”

Power Quality Measurement Results for a Configurable Urban Low-Voltage DC Microgrid

“…Measurement campaigns have been planned for existing LV DC grid trials, such as in Malaga Smart City [27]. Furthermore, initial reference systems for DC power [28] and electricity meter testing in the presence of AC distortions [29] have been developed.…”