[Studies in Computational Intelligence 481] Artur Babiarz, Robert Bieda, Karol Jędrasiak, Aleksander Nawrat (auth.), Aleksander Nawrat, Zygmunt Kuś (eds.) - Vision Based Systemsfor UAV Applications (2013, Sprin

280 A. Nawrat et al.
• 1-phase electronic meters with PLC modems
• 3-phase electronic meters with PLC modems
• 1-phase electronic meters without modems
• 3-phase electronic meters without modems
• 1-phase inductive meters
• 3-phase inductive meters
The scope of the study covered multiple meters of a single type at all times so that
repeatability of the results obtained could be ascertained. Typical meters that are
commonly used were chosen for the research. Intentionally, however, type markings
were changed.
During measurements the meters were powered by rated voltage, and measurements
of electrical currents were conducted independently in voltage circuits
of each phase. Current circuits of particular phases were not loaded during the
measurements, and therefore powers obtained during the measurements come
from power loss only. All the results were obtained on the basis of representative
measurement series for which both typical and maximum values were defined. To
demonstrate the differences in measurement results fragments from measurement
series for selected 1-phase meters with various communication modems are shown
below.
2.1 Measuring Circuit Used for 1-Phase Meters
Fig. 2 shows a circuit intended for indirect measurements of currents 1-phase meter
voltage circuits, including inductive and electronic meters. In the circuit, a
current/voltage converter was used in the form of a shunt R3, on which voltage
components (active and passive) are measured by means of vector nanovoltmeter
(LIA). Referential voltage Uref is taken from a resistor R2 within a resistance
divider of the voltage supplied from the examined phase feeding the electrical
energy meter. Current circuits were not loaded during loss power measurements,
Zio = ∞. Meter power loss (real power P1h, reactive power Q1h and apparent
power S1h) for feeding phases were calculated on the basis of measured current
components in meter’s input voltage circuits.
Fig. 2. Circuit intended for indirect measurements of currents in 1-phase meter voltage
circuits