Electrical activity sensor device for detecting electrical activity and electrical activity monitoring apparatus

Patent metadata

Field	Value
Publication number	US-2016351994-A1
Application number	US-201615168040-A
Country	US
Kind code	A1
Filing date	May 28, 2016
Priority date	May 29, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

The invention relates to electrical activity sensor attachable to a power cable of an electrical device for detecting an impulse generated in the power cable in response to a change in electrical power state of the electrical device. The electrical activity sensor includes an antenna assembly having an antenna element operable to magnetically couple with an electrical pulse generated in the power cable to induce an electrical signal in response to a change in electrical power state of the electrical device. The antenna element is shaped in a plurality of loops.

First claim

1 . An electrical activity sensor attachable to a power cable of an electrical device for detecting an impulse generated in the power cable in response to a change in electrical power state of the electrical device, the electrical activity sensor comprising an antenna assembly including:
an antenna element operable to magnetically couple with an electrical pulse generated in the power cable in response to a change in electrical power state of the electrical device to induce an electrical signal; wherein at least a part of the antenna element is formed in a plurality of loops for magnetic coupling with the electrical pulse in the power cable

2 . An electrical activity sensor according to claim 1 wherein the plurality of loops are configured to form the shape of the figure 8.

3 . An electrical activity sensor according to claim 1 wherein the antenna element is formed in three or more loops arranged along a common axis.

4 . An electrical activity sensor according to claim 1 wherein the plurality of loops are sized based on the circumference of the power cord.

5 . An electrical activity sensor according to claim 4 wherein the side of each loop of the plurality of loops has an axial length corresponding to half of the circumference of the power cord

6 . An electrical activity sensor according to claim 1 wherein the antenna assembly comprises at least one dipole type antenna configured operate as a half wave dipole in the operating frequency range of the antenna element and to magnetically couple to the antenna element wherein the dipole type conductor is operable to wirelessly transmit data representative of the power state change of the electrical device from the antenna assembly to a remote radio frequency data reader.

7 . An electrical activity sensor according to claim 6 wherein the antenna element is coupled to the dipole type antenna at a coupling distance from one end of the dipole type antenna, the coupling distance being based upon at least one of the input impedance of a radio frequency identification circuit of the antenna element, the radiation resistance of the dipole type antenna.

8 . An electrical activity sensor according to claim 1 wherein the size of the antenna element is adjusted according to the input impedance of a radio frequency identification circuit of the antenna element at the RF operating frequency.

9 . An electrical activity sensor according to claim 1 wherein the distance between the antenna element and the dipole type antenna is adjusted according to the input impedance of the radio frequency identification circuit of the antenna element at the RF operating frequency.

10 . An electrical activity sensor according to claim 1 wherein the antenna element comprises a RFID tag.

11 . An electrical activity sensor device for monitoring the electrical status of an electrical device, the electrical activity sensor device comprising:
a power cable for supplying power to an electrical device, the power cable comprising electrical power wires, wherein at least a part of each electrical power wire is formed in a loop to magnetically couple with an antenna element attached to the power cable to induce a detectable electrical signal when the electrical device changes power state.

12 . An electrical activity sensor according to claim 11 wherein each wire is shaped to form two parallel loops

13 . An electrical activity sensor according to claim 11 wherein each wire is shaped to form a plurality of loops in an axial direction along its length.

14 . An electrical activity sensor according to claim 11 wherein each wire is shaped to form a plurality of loops in a direction perpendicular to the axial length.

15 . An electrical activity monitoring system comprising
at least one electrical activity sensor device attachable to a power cable of an electrical device for detecting an impulse generated in the power cable in response to a change in electrical power state of the electrical device, the electrical activity sensor comprising an antenna assembly including: an antenna element operable to magnetically couple with an electrical pulse generated in the power cable in response to a change in electrical power state of the electrical device to induce an electrical signal; wherein at least a part of the antenna element is formed in a plurality of loops for magnetic coupling with the electrical pulse in the power cable a reader module for reading data received wirelessly from an electrical activity sensor; and a monitor device for determining from the data received by the reader module, if any electrical device of the network has changed electrical power status.

Assignees

• Thomson Licensing

Inventors

• Louzir Ali
• Le Naour Jean-Yves
• Ruee Maxime

Classifications

• H01Q7/00

  Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop · CPC title

• G06K7/10316

  using at least one antenna particularly designed for interrogating the wireless record carriers (antennas in general H01Q1/22) · CPC title

• G01R19/2513

  Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging · CPC title

• G01R15/181

  using coils without a magnetic core, e.g. Rogowski coils · CPC title

• H01Q9/065

  Microstrip dipole antennas (patch antenna H01Q9/0407) · CPC title