System and method for electrical power and/or energy metering on multiple channels
A system ( 10 ) for power and/or energy consumption metering on an AC powerline network ( 1 ) supplying a plurality of channels (C 1 , C 2 , . . . , C n ) with a respective electrical load (L 1 , L 2 , . . . , L n ), comprising: A central unit ( 11 ) connected to the AC powerline network ( 1 ), comprising a single central voltmeter ( 110 ) supplied by a power supply unit ( 112 ); A plurality of clamped-on units ( 12 ), distributed over each channel (C 1 , C 2 , . . . , C n ) to be measured, each clamped-on unit ( 12 ) being clipped around existing cables, and comprising a current transformer ( 120 ) in order to measure current values The plurality of clamped-on units ( 12 ) are connected to the central unit ( 11 ) for data transmission and synchronization, and for power supply by the power supply unit ( 112 ).
1. System for power and/or energy consumption metering on an alternating current (AC) powerline network, said network supplying a plurality of channels with a respective electrical load, the system comprising:
A central unit connected to said AC powerline network, said central unit comprising a single central voltmeter and a power supply unit, said central voltmeter being supplied by the power supply unit;
A plurality of clamped-on units, distributed over each channel to be measured, each clamped-on unit being clipped around existing cables of said AC powerline network, and comprising a current transformer in order to measure current values,
wherein said plurality of clamped-on units are connected to the central unit for data transmission and synchronization, and for power supply by said power supply unit,
wherein a wireless link is provided between the plurality of clamped-on units and the central unit, wherein said clamped-on units are mounted on an electrical panel, and wherein an induction coil is further provided around said electrical panel for power transmission to said clamped-on units, and data transmission to and from said clamped-on units.
2. System for power and/or energy consumption metering on an AC powerline network according to claim 1 , wherein said AC powerline network supplies one, two or three-phase electrical power, and said single central voltmeter is a voltage analog-to-digital converter (ADC) system sampling voltage values, for each phase, at frequencies over 100 Hz, preferably over 1 KHz, and wherein said clamped-on units sample current values at the same frequency.
3. System for power and/or energy consumption metering on an AC powerline network according to claim 1 , wherein said central unit further comprises at least one communication interface.
4. System for power and/or energy consumption metering on an AC powerline network according to claim 1 , wherein each of said clamped-on units are fitted with an embedded digital signal processor for dedicated local computation of the energy consumption of each channel.
5. System for power and/or energy consumption metering on an AC powerline network according to claim 1 , wherein said central unit is fitted with a central digital processor for centralized computation of the energy consumption of each channel.
6. Method for power and/or energy consumption metering on an AC powerline network using the system according to claim 1 , wherein voltage values are first measured at the central unit, then current values are measured at the clamped-on units for each channel, yielding instant power values, and eventually energy consumption is then derived by a digital signal processor integrating synchronised voltage and current values, wherein a wireless link is provided between the plurality of clamped-on units and the central unit, wherein said clamped-on units are mounted on an electrical panel, and wherein an induction coil is further provided around said electrical panel for power transmission to said clamped-on units, and data transmission to and from said clamped-on units.
7. Method for power and/or energy consumption metering on an AC powerline network according to claim 6 , wherein voltage values are sampled at a frequency higher than 100 Hz, and preferably over 1 kHz, by a voltage ADC system at the central unit, and current values are also sampled at a frequency higher than 100 Hz, and preferably over 1 kHz, by a current ADC at each clamped-on unit.
8. Method for power and/or energy consumption metering on an AC powerline network according to claim 7 , wherein said sampled voltage values are broadcasted to every clamped-on unit, and power and/energy consumption for each channel is subsequently computed by an embedded digital signal processor of each clamped-on unit based on sampled current values and received said sampled voltage values.
9. Method for power and/or energy consumption metering on an AC powerline network according to claim 7 , wherein said sampled current values are transmitted back to the central unit, and power and/or energy consumption is subsequently computed by a central digital signal processor of the central unit based on the centrally sampled voltage values.
10. Method for power and/or energy consumption metering on an AC powerline network according to claim 6 , wherein a preliminary binding process is foreseen to assign a unique identifier to specific channels.
11. Method for power and/or energy consumption metering on an AC powerline network according to claim 10 , wherein contextual information can be provided to each clamped-on unit upon installation and then imported to said central unit.