Power quality analysis system and method for monitoring from the outside of multiconductor cables
A power quality analysis system is configured to carry out a power quality analysis in an electrical environment. The system comprises one or more power consuming units each electrically connected to a main power supply by a multiconductor (multicore) cable and one or more power quality sensors configured to provide one or more power quality analysis measurements. The one or more power quality sensors are clamp-on power quality sensors configured to provide one or more power quality analysis measurements when the clamp-on power quality sensors are clamped onto the outside of or arranged in the proximity of the multiconductor cable. The clamp-on power quality sensors are configured to provide the one or more power quality analysis measurements without being electrically connected to any of the conductors of the multiconductor cable.
1. A power quality analysis system for carrying out power quality analysis and detecting power quality distortions in an electrical environment, comprising:
one or more power consuming units each electrically connected to a main power supply by a multiconductor cable that comprises a plurality of conductors insulated from each other;
a plurality of clamp-on power quality sensors configured to provide one or more power quality analysis measurements and to detect power quality distortions when the clamp-on power quality sensors are clamped onto an outside of or arranged in proximity of the multiconductor cable, wherein the clamp-on power quality sensors are not electrically connected to any of the conductors of the multiconductor cable;
wherein each of the clamp-on power quality sensors comprises a plurality of sub-sensors selected from coils, Hall-effect sensors, and/or capacitive probes positioned so that different sub-sensors measure different superpositions of combined electromagnetic fields induced by the conductors of the multiconductor cable;
at least one central power quality unit sensor measuring overall power quality;
a calculation unit adapted to use a mathematical statistical model which combines measurements made by the clamp-on power quality sensors and measurements made by the central power quality unit sensor, the mathematical statistical model comprising:
1) a mathematical function component modelling latent mapping from the central power quality unit sensor measurements onto the clamp-on power quality sensor measurements; and
2) a stochastic component modelling measurement noise and a part of each central power quality unit sensor measurement associated with usage not measured by the clamp-on power quality sensors.
2. The power quality analysis system according to claim 1 , further comprising a time synchronization unit that synchronizes the measurements from the clamp-on power quality sensors and the central power quality unit sensor at a predefined frequency.
3. The power quality analysis system according to claim 1 , wherein the clamp-on power quality sensors measure both the magnetic field and the electric field of the multiconductor cable.
4. The power quality analysis system according to claim 1 , wherein the central power quality unit sensor measures both the magnetic field and the electric field of the multiconductor cable.
5. The power quality analysis system according to claim 1 , wherein at least some of the clamp-on power quality sensors and/or the central power quality unit sensor communicate(s) wirelessly with one or more external devices.
6. The power quality analysis system according to one claim 1 , further comprising one or more energy harvesting devices powering at least some of the clamp-on power quality sensors and/or the central power quality unit sensor.
7. The power quality analysis system according to claim 1 , further comprising one or more energy harvesting devices harvesting energy, measuring voltage in the multiconductor cable, or both.
8. The power quality analysis system according to claim 1 , wherein the central power quality unit sensor pre-analyzes the measured data to reduce data load.
9. A method for carrying out a power quality analysis and detecting power quality distortions in an electrical environment, comprising:
providing a power quality analysis system comprising:
one or more power consuming units each electrically connected to a main power supply by a multiconductor cable that comprises a plurality of conductors insulated from each other;
a plurality of clamp-on power quality sensors configured to provide one or more power quality analysis measurements and to detect power quality distortions when the clamp-on power quality sensors are clamped onto an outside of or arranged in proximity of the multiconductor cable, wherein the clamp-on power quality sensors are not electrically connected to any of the conductors of the multiconductor cable;
wherein each of the clamp-on power quality sensors comprises a plurality of sub-sensors selected from coils, Hall-effect sensors, and/or capacitive probes positioned so that different sub-sensors measure different superpositions of combined electromagnetic fields induced by the conductors of the multiconductor cable;
at least one central power quality unit sensor measuring overall power quality; and
applying a mathematical statistical model which combines measurements made by the clamp-on power quality sensors and measurements made by the central power quality unit sensor, the mathematical statistical model comprising:
1) a mathematical function component modelling latent mapping from the central power quality unit sensor measurements onto the clamp-on power quality sensor measurements; and
2) a stochastic component modelling measurement noise and a part of each central power quality unit sensor measurement associated with usage not measured by the clamp-on power quality sensors.
10. The method according to claim 9 , further comprising synchronizing measurements from the clamp-on power quality sensors and the central power quality unit sensor at a predefined frequency.
11. The method according to claim 9 , wherein the clamp-on power quality sensors measure both the magnetic field and the electric field of the multiconductor cable.
12. The method according to claim 9 , wherein the central power quality unit sensor measure both the magnetic field and the electric field of the multiconductor cable.
13. The method according to claim 9 , wherein at least some of the clamp-on power quality sensors and/or the central power quality unit sensor communicate(s) wirelessly with one or more external devices.
14. The method according to claim 9 , wherein at least some of the clamp-on power quality sensors and/or the central power quality unit sensor is/are powered by at least one energy harvesting device.
15. The method according to claim 14 , wherein the at least one energy harvesting device harvests energy, measures voltage in the multiconductor cable, or both.
16. The method according to claim 9 , further comprising pre-analyzing the data measured by the central power quality unit sensor to reduce data load.