SUPPORT FOR A MEASURING SYSTEM FOR AT LEAST ONE PARAMETER OF AN ELECTRICAL CABLE

Abstract

This support, designed to be removably positioned around an electrical cable, contains a system for measuring at least one cable parameter. The measurement system comprises measuring devices and measurement processing devices connected to them. It is made of two parts, each housing at least partially the measuring devices. Each part has a first and a second end. The two parts are joined at their first end by a hinge along a first axis of the support. Both parts of the support also house at least partially the processing devices. The support includes at least one element for holding the processing devices in position relative to the support. The two parts of the support do not come into contact with each other in a region extending from the hinge to and including the second ends, along a second axis of the support perpendicular to the first axis.Figure for the abridged version: Fig. 1.

Description

Title of the invention: SUPPORT FOR A MEASURING SYSTEM FOR AT LEAST ONE PARAMETER OF AN ELECTRICAL CABLE

[0001] The present invention relates to a support for a measurement system for at least one parameter of an electrical cable.

[0002] The invention relates to the field of electrical cables intended for power transmission and / or data transmission. It is particularly applicable to the optimization of power distribution in buildings. The support of the present invention can, for example, be used as a support for a device for simultaneously measuring the instantaneous current intensity in each phase or in each conductor of an alternating or direct current, single-phase, multi-conductor, or polyphase electrical cable.

[0003] A device for measuring currents in the conductors of a sheathed cable of a polyphase network is known from document EP 2 776 853 B1.

[0004] This prior art measuring device is in the form of a measuring ring designed to surround a section of the sheathed cable. The ring comprises two articulated parts fixed to each other by a clasp that holds the ring in position on the cable.

[0005] For current measurement, this known measuring device comprises at least three magnetic sensors arranged around a central orifice through which the cable to be measured passes when the measuring ring surrounds the cable. The ring comprises a number of magnetic sensors greater than the number of conductors whose current is to be measured.

[0006] This known device further comprises a calculation device configured to: access a library of matrices [K] and [K]+, with [I] = [K]+.B for a given cable configuration and a given angular position of the sensors around this given cable, [I] being a current vector through the cable having the given configuration when a magnetic field vector [B] is measured on the sensors and [K]+ being a pseudo-inverse matrix of the matrix [K]; form a vector [B] including a magnetic field measurement of each of the sensors; for different cable configurations and different angular positions of the sensors relative to these cables, calculate a residual vector [R] = [K].[K]+.[B] - [B]; select the matrix [K]+ for which the norm of the vector [R] is minimal; calculate [I] = [K]+ .B, where [K]+ is the selected matrix.

[0007] This known measuring device has several drawbacks.

[0008] On the one hand, its use requires the creation and maintenance of a matrix library and the management of access to this library, which consumes in particular time for the creation and updating of the library, storage space to store the library and electrical energy to carry out all the operations related to the existence and use of the library.

[0009] On the other hand, the quality and repeatability of the measurement are not guaranteed: document EP 2 776 853 B1 does not in fact mention any means of holding in position specifically concerning the electronic means of processing the magnetic field measurements carried out on the cable, when the measuring device is positioned around this cable, nor any means of protecting these electronic processing means, either against degradations related to the conditions of the environment in which the device is located, for example due to weather conditions, or against degradations due to mechanical action such as deformation under pressure, or even crushing.

[0010] Other known devices for measuring the instantaneous current intensity in each conductor of a polyphase, or multi-conductor cable, generally consist of successively measuring, by means of a current clamp, the current intensity in each of the conductors.

[0011] These operations are time-consuming and generally provide inaccurate results.

[0012] Therefore, there is no practical technical solution on the market for measuring one or more parameters of an electrical cable quickly and with high measurement quality, i.e. not only accurately, but also with a reduced risk of damage to the measuring device.

[0013] The present invention aims to remedy the aforementioned drawbacks of the prior art.

[0014] To this end, the present invention proposes a support containing a measurement system for at least one parameter of an electrical cable, this support being adapted to be positioned around the cable in a removable manner, the measurement system comprising at least one device for measuring at least one parameter and at least one device for processing measurements of at least one parameter, the at least one processing device being connected to the at least one measuring device; the support being made in a first and a second part, each of which houses at least one part of at least one measuring device; the first and second parts of the support each having a first end and a second end, the first and second parts being assembled at their first end by means of a joint along a first axis of the support, the joint making the first and second parts of the support mobile around the first axis; the support being remarkable in that: - the first and second parts of the support each also house at least one part of at least one processing device; - the support also includes at least one element for holding in position at least one processing device relative to the support; and - the first and second parts of the support do not come into mutual contact in a region extending from the joint to the second inclusive ends, along a second axis of the support perpendicular to the first axis.

[0015] The present invention makes it possible to improve the quality of the measurement performed.

[0016] Indeed, on the one hand, measurements of high precision and of a excellent repeatability thanks to the maintenance in position of the measurement processing device(s) relative to the support and on the other hand, the risk of damage to this processing device(s) is reduced thanks to the fact that the first and second parts of the support never come into contact, i.e. there is always a free space between the two parts of the support, whether the latter is in open or closed position.

[0017] This free space effectively prevents mechanical contact between the first and second parts of the support in the closed position, whether this closed position is assumed when the measuring device is not in use and is, for example, stored or transported, or whether it is assumed when the measuring device is placed around a cable for which at least one parameter is to be measured using the measuring device. Thus, the processing device presents a very low risk of deformation and crushing when the support is closed.

[0018] Moreover, the support according to the invention presents an easy installation around the cable, because it is not necessary in particular to install each measuring device individually.

[0019] The invention offers numerous applications, such as the identification of unbalanced current distributions sometimes indicative of a faulty power supply, the anticipation of cable failures when a conductor reaches an excessive temperature or the reduction of electrical energy consumption in an installation.

[0020] In a particular embodiment, the element for holding at least one processing device in position relative to the support is a locking clip.

[0021] However, this embodiment is not limiting, because any other mechanical system that ensures this holding in position can be used.

[0022] In a particular embodiment, at least one measuring device includes at least one magnetic field sensor and at least one measurement processing device includes at least one integrated circuit board, known in English as a PCB (“Printed Circuit Board”), at least one parameter being, in this particular embodiment, the intensity of an instantaneous current flowing in the cable.

[0023] In this particular embodiment, by way of non-limiting examples of use of the support: when the cable is single-phase, at least one measuring device is adapted to measure the intensity of the instantaneous current flowing in the phase of the cable; when the cable is a multi-conductor cable, at least one measuring device is adapted to simultaneously measure the intensities of the instantaneous currents flowing respectively in all the conductors of the cable; and when the cable is polyphase, at least one measuring device is adapted to simultaneously measure the intensities of the instantaneous currents flowing respectively in all the phases of the cable.

[0024] In this particular embodiment, at least one measurement processing device may, for example, comprise two integrated circuit cards housed respectively in the first and second parts of the support, and the two integrated circuit cards may be in mechanical contact with each other. Thus, the positioning of the measurement processing device relative to the support is even better.

[0025] By way of non-limiting example, if the measuring device includes several magnetic field sensors, these sensors can, for example, be arranged on the integrated circuit boards, for example, in a distributed manner. If, for example, the first and second parts of the support are semicircles, the sensors can be distributed in each of the first and second parts along the circumference of a semicircle. In such a non-limiting embodiment, the mechanical contact between the two integrated circuit boards when the support is in the closed position allows the magnetic sensors to form a perfect circle, which further increases the measurement accuracy.

[0026] In this particular embodiment, the element for holding in position at least one processing device relative to the support ensures that the two integrated circuit cards remain in mutual mechanical contact.

[0027] In this particular embodiment where at least one measuring device includes at least one magnetic field sensor and at least one measurement processing device includes at least one integrated circuit card, at least one parameter being the intensity of an instantaneous current flowing in the cable, the first and second parts can be surrounded by electromagnetic shielding.

[0028] This shielding prevents the penetration of electromagnetic interference that could distort the measurement; such interference could be due, for example, to to the permanent Earth's magnetic field and to possible sources of electromagnetic fields located near the cable and sensors.

[0029] In a particular embodiment, the support further comprises at least one additional magnetic field sensor adapted to measure the Earth's magnetic field.

[0030] This allows the value of the Earth's magnetic field to be taken into account, which can thus be subtracted when processing the magnetic field values ​​collected by the sensors.

[0031] According to a particular feature, at least one additional sensor can be housed in the support, which makes it possible to better protect this sensor against degradation and to obtain a compact support.

[0032] Alternatively, at least one additional sensor can be arranged on the support and outside the support, making it more accessible.

[0033] According to a particular feature, at least one additional sensor may be removable, which allows the user of a single support to opt on a case-by-case basis for a version of the support with or without this additional sensor.

[0034] In a particular embodiment, the joint is a hinge.

[0035] In the particular embodiment where the processing device comprises two integrated circuit cards housed respectively in the first and second parts of the support, the hinge, which implements a pivot link allowing rotation but blocking translation, ensures mutual mechanical contact between the two integrated circuit cards.

[0036] Alternatively, the joint can be a ball joint, which offers more degrees of freedom to the first and second parts of the support and facilitates their positioning around a cable.

[0037] In a particular embodiment, the first and second parts are half-rings, the annular shape being particularly suitable for positioning the support around a cable.

[0038] This configuration allows for quick installation of the support around the cable, which is therefore housed in the center of the circular opening formed by the joining and closing of the two half-rings, thus forming a ring through which the cable to be measured passes in its center.

[0039] In a particular embodiment, the support further comprises a communication device adapted to transmit data from at least one measuring device and / or at least one processing device to the outside.

[0040] This makes it possible, for example, to provide the emitted data to various recipients, who may, by reviewing this data and possibly analyzing it, decide what actions to take with regard to the measured cable and the installation served by that cable.

[0041] According to a particular feature, the communication device may include at least one antenna, which is a simple means of transmitting data over the air, for example via radio frequency waves.

[0042] For the same purpose as indicated above, the present invention further proposes an electrical cable arrangement comprising an electrical cable having a plurality of conductors, remarkable in that it also comprises at least one support as briefly described above placed around the cable.

[0043] The cable arrangement according to the invention has the same advantages as the support.

[0044] In a particular embodiment, the cable arrangement comprises a plurality of supports such as that described briefly above, placed around the cable at predetermined intervals from each other.

[0045] This ensures adequate measurement of current intensities in the cable conductors in the event that these conductors are twisted in such a way that they are likely to influence the sensitivity of the current measurement.

[0046] Still with the same objective as indicated above, the present invention also proposes a method for measuring the current intensity in an electrical cable comprising a plurality of conductors by means of at least one measuring device and at least one measurement processing device, the at least one measuring device and the at least one processing device being part of a support as briefly described above, the measuring device comprising a plurality of magnetic field sensors, the method being remarkable in that it consists of simultaneously measuring the current intensity in the conductors of the plurality of conductors, by means of the at least one measuring device and the at least one processing device, by carrying out steps consisting of: place the plurality of magnetic field sensors around the cable, in at least one location on the cable; to simultaneously measure, for each of the conductors, at least one component of the magnetic field produced by the current flowing in the conductor, by means of the plurality of magnetic field sensors; for each of the conductors, determine the angle between the conductor and the magnetic field sensor of the nearest plurality of magnetic field sensors, this angle being defined with respect to the center of the cable and by assimilating the conductors and the sensors to points; The current intensities in the conductors are related to the components of the magnetic field measured by the relation B = kMI where B is the matrix of components of the magnetic field, I is the matrix of current intensities, M is a matrix comprising a plurality of proportionality coefficients depending on the angles between the conductors and the magnetic field sensors and k is a predetermined coefficient, calculate the inverse M 1 of the matrix M, so as to deduce the values ​​of the current intensities I = (po / 2ir).M '.B, where po is an equivalent magnetic permeability which takes into account the presence of insulating materials in the cable, at least one measurement processing device being adapted to receive the values ​​of the components of the magnetic field and to apply the steps of angle determination and inverse matrix calculation to deduce the intensity of the current flowing in each of the conductors.

[0047] The method according to the invention has the same advantages as the support.

[0048] Furthermore, with regard more specifically to measuring the intensity of the current(s) flowing in a cable, the method according to the invention makes it possible, in particular, to measure the current intensity in all the cable conductors in a single operation and to obtain extremely precise results quickly, without having to remove the cable sheath. Moreover, the installation of the magnetic field sensors around the cables is easy and does not cause any damage, marking, or deformation to the cables. In addition, since the position of the magnetic field sensors relative to the cable conductors is unknown, taking into account the angular offset between the sensors and the conductors makes it possible to increase the accuracy of the current values ​​obtained.

[0049] In a particular embodiment, the measurement step consists of simultaneously measuring, for each of the conductors, the tangential component and the radial component of the magnetic field produced by the current flowing in the conductor, by means of the plurality of magnetic field sensors.

[0050] This makes it possible to minimize the error on the intensity values ​​obtained, i.e. to further increase the precision of these values. Brief description of the drawings

[0051] Other aspects and advantages of the invention will become apparent from the following detailed description of particular embodiments, given by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0052] [Fig.1] is a schematic view illustrating an aspect of the technical problem to which the support according to the present invention provides a solution.

[0053] [Fig.2] is a schematic representation of a support according to the present invention, in a non-limiting example of application to the measurement of a five-conductor electrical cable.

[0054] [Fig.3] is a schematic representation of a support and cable arrangement electrical conforming to the present invention, in a particular embodiment.

[0055] [Fig.4] is a schematic representation of an electrical cable arrangement in accordance with the present invention, in another particular embodiment.

[0056] [Fig.5] is a flowchart illustrating steps in a process conforming to the present invention, in a particular embodiment.

[0057] [Fig.6] is a geometric representation illustrating different parameters used in a process according to the present invention, in a non-limiting example where the electrical cable in question comprises five conductors. Description of method(s) of implementation

[0058] Fig. 1 illustrates one aspect of the problem addressed by the present invention: it is a theoretical view which schematically represents a relative position that two parts of measurement processing devices could take, for example two integrated circuit cards 11 and 12, these two integrated circuit cards being adapted to process measurements carried out on an electrical cable 32 comprising a plurality of conductors 34.

[0059] The two integrated circuit cards 11 and 12 are housed in two parts of a support (not shown in [Fig. 1], described in detail later with reference to [Fig. 2]). The two parts of the support close around the cable 32 for taking measurements and processing these measurements of one or more parameters of the cable 32, for example, physical parameters such as the current flowing through it and / or the temperature and / or the degree of humidity and / or any other quantity relating to the cable 32 itself and / or the current flowing through it. The processing of the measurements taken on the cable is performed by the integrated circuit cards 11 and 12.

[0060] As shown in [Fig. 1], which is magnified compared to reality, when the two parts of the support close around the cable 32 and are tightened, an angle R can form between the planes of the two integrated circuit boards 11 and 12. This can induce deformation of one or both boards 11 and 12, or even of the entire support. This can then cause errors in the measurements taken and / or in the processing of these measurements, for example, in determining the intensity of the instantaneous current(s) flowing in the cable 32. The repeatability of the measurements can be compromised. The reliability and quality of the measurements can be significantly affected.

[0061] Fig. 2 shows a support 20 conforming to the present invention providing a solution which resolves in particular this problem.

[0062] The support 20 contains a measurement system for at least one parameter of the electrical cable 32.

[0063] The support 20 is adapted to be positioned around the cable 32 in a removable manner.

[0064] The measurement system comprises at least one device for measuring at least one parameter and at least one device for processing measurements of at least one parameter. The at least one processing device is connected to the at least one measuring device.

[0065] The support 20 is made in a first part 21 and a second part 22. The first part 21 houses at least a part of at least one measuring device and similarly, the second part 22 houses at least a part of at least one measuring device.

[0066] The first and second parts 21, 22 of the support 20 each having a first end (designated on the drawing by reference 210 for the first part 21 and by reference 220 for the second part 22) and a second end (designated on the drawing by reference 230 for the first part 21 and by reference 240 for the second part 22).

[0067] The first and second parts 21, 22 of the support 20 are assembled at their first end 210, 220 by means of a joint 26 along a first axis of the support 20 designated on the drawing by the reference z. The joint 26 makes the first and second parts 21, 22 of the support 20 movable around the first axis z.

[0068] In accordance with the present invention, the first and second parts 21, 22 of the support 20 each further house at least one part of at least one processing device, which in the particular embodiment shown in [Fig.2] is the assembly formed by the integrated circuit cards 11 and 12.

[0069] According to the present invention, the support 20 further comprises at least one element for holding in position at least one processing device relative to the support 20. The element for holding in position at least one processing device relative to the support 20 may, for example, be a locking clip.

[0070] According to the present invention, the first and second parts 21, 22 of the support 20 do not come into mutual contact in a region extending from the joint 26 to the second ends 230, 240 inclusive, along a second axis of the support, designated in the drawing by reference x. The second axis x is perpendicular to the first axis z. In other words, there is always a free space 24 between the first part 21 of the support 20 and the second part 22 of the support 20.

[0071] Fig. 3 illustrates a particular embodiment of the invention in which the measured parameter is the intensity of an instantaneous current flowing in the electrical cable 32.

[0072] The cable 32 can be a single-phase, polyphase, or multi-conductor cable and can carry alternating or direct current. N denotes the number of conductors in the cable. These conductors are not necessarily identical.

[0073] In the non-limiting example of [Fig. 3], the cable 32 is polyphase and the invention is based on the local measurement of at least one component of the magnetic field emitted by the current sources, which are here the N conductors, by means of magnetic field sensors. Thus, at least one measuring device comprises at least one magnetic field sensor 36 and at least one measurement processing device comprises at least one integrated circuit board 11, 12, at least one parameter being the intensity of an instantaneous current flowing in the cable 32.

[0074] In short, given that a polyphase cable has several current densities from its N conductors, we can first calculate the magnetic field produced by the current using the Biot-Savart law, then invert all the local measurements of magnetic field components by determining an inverse matrix, in order to obtain the current intensities from the N current sources.

[0075] Thus, as shown in the flowchart of [Fig. 5], the method according to the invention for measuring the current intensity in an electrical cable comprising a plurality of conductors consists of simultaneously measuring, by means of at least one measuring device and at least one measurement processing device, the current intensity in the conductors of the plurality of conductors 34 by carrying out a first step 11 consisting of placing a plurality of magnetic field sensors 36 around the cable 32, at at least one location on the cable. The at least one measuring device and the at least one processing device are part of a support 20 according to the present invention.

[0076] Step El may for example consist of fixing around the cable 32 one or more supports 20 according to the invention containing the plurality of sensors 36. The support 20 according to the invention is described further below.

[0077] Then a step E2 consists of simultaneously measuring, for each of the conductors 34 of the cable 32, at least one component of the magnetic field produced by the current flowing in that conductor.

[0078] These simultaneous measurements are carried out using the measuring device which includes the plurality of magnetic field sensors 36.

[0079] In a particular embodiment, the plurality of magnetic field sensors 36 can measure for each conductor 34 only the tangential component or only the radial component of the magnetic field.

[0080] Alternatively, for greater accuracy, the plurality of magnetic field sensors 36 can measure for each conductor 34 simultaneously and at the same time the tangential component and the radial component of the magnetic field.

[0081] Then, in step E3, for each of the conductors, the angle α between that conductor and the magnetic field sensor of the plurality of sensors is determined. of the nearest magnetic field. The angle α is defined relative to the center of the cable cross-section, treating the conductors and sensors as points. Indeed, for simplicity, we assume that each conductor has an infinitesimally small cross-section and that the magnetic field detected by each sensor is localized at a point corresponding to the sensor's location.

[0082] Figure 6 schematically illustrates, by way of non-limiting example, a circular cross-section cable comprising five conductors regularly distributed within the cable, which are considered as five points Cl to C5 equidistant from each other on the circumference of a circle T. Only the magnetic field sensor closest to conductor Cl has been shown and is symbolized by point A. The radius of circle T is denoted by r, the distance between conductor Cl and sensor A is denoted by db, the line segment connecting sensor A and the center of circle T is denoted by d'i, the angle at point A between the line segment d'i and the line segment connecting conductor Cl and point A is denoted by [3]. The magnetic field detected by sensor A is represented by the vector BH which is orthogonal to the line segment connecting conductor Cl and point A.

[0083] For a cable comprising N conductors, each producing a magnetic field B, i = 1, ..., N, the component BA of the magnetic field at point A originating from the N conductors is defined as follows:

[0084] [Math.l] 1=1^1 — — ^i= 12?ryd; / / ^im

[0085] where: Bim is the component of the magnetic field coming from the ith conductor captured by the ith sensor; the angles a; and [3; are defined for the ith conductor in a similar way to the angles a and [3 defined above, respectively; d; denotes the distance between the i-th conductor and the nearest sensor; Po is an equivalent magnetic permeability that takes into account the presence of insulating materials in the cable; r is, as defined above, the radius of circle T; and Iim is the value of the intensity of the current flowing in the ith conductor and deduced from the magnetic field measurement carried out by the m1st sensor.

[0086] The number of magnetic field sensors 36 is at least equal to the total number N of conductors 34 of the cable 32.

[0087] Thus, the current intensities in the conductors are related to the measured magnetic field components by the relation B = kMI where B is the matrix

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097] components of the magnetic field measured in all conductors by all sensors, I is the matrix of current intensities flowing in all conductors, M is a matrix comprising a plurality of proportionality coefficients depending on the angles between the conductors and the magnetic field sensors and k is a predetermined coefficient. It follows that I = (po / 2ir).M '.B, where M 1 is the inverse matrix of M. Thus, as shown in [Fig.5], following step E3 of determining the angle a between each conductor and the nearest sensor, a step E4 is carried out consisting of calculating the inverse matrix M4, so as to deduce the values ​​of the current intensities I in all the conductors of the cable. As a non-limiting example, for N = 5 conductors and five sensors of magnetic fields placed respectively at points A, B, C, D and E, the expression The analytical method used to deduce the current intensities in conductors is the next: [Math.2] i-cosW i-œsW i 'cosW t -^( / A) IBa\ bb BC BD \Bei where h, i = 1, ..., 5 denotes the intensity of the current flowing in the i-th conductor and Ba, Bb, Bc, Bd and Be denote the components of the magnetic field respectively measured by the five sensors. The equivalent magnetic permeability po is a macroscopic permeability, which makes the calculation simpler than if we considered the local magnetic permeability. In a particular embodiment, the angle α between this conductor and the magnetic field sensor of the nearest plurality of magnetic field sensors is determined so as to maximize the following function F: [Math.3] where h denotes the intensity of the current flowing in the i-th conductor. There are various known mathematical convergence methods for maximizing F, such as the Levenberg-Marquardt algorithm (also called the LM algorithm) or the Nelder-Mead method.

[0098] As shown in [Fig.3], a support 20 according to the present invention, for measuring the current intensity in an electrical cable 32 comprising a plurality of conductors 34, comprises a plurality of magnetic field sensors 36 (five in the non-limiting example shown) and a processing device comprising integrated circuit cards 11, 12, the processing device being arbitrarily shown separately to simplify the schematic view of [Fig.3], but being contained in the first and second parts 11, 12 of the support 20 as described above with reference to [Fig.2].

[0099] The processing device is adapted to receive the values ​​of the magnetic field components measured by the plurality of sensors 36 and to apply the angle determination steps E3 and inverse matrix calculation steps E4 of the process described above, in order to deduce the intensity of the current flowing in each of the conductors 34.

[0100] The support 20 further comprises the first and second parts 11,12 containing the plurality of magnetic field sensors 36.

[0101] In the particular embodiment illustrated, the support 20 has a section formed of two half-rings 311 and 312, adapted to the positioning of the support 20 around the cable 32, the two half-rings 311 and 312 defining by their assembly an opening through which the cable 32 passes. In the particular embodiment illustrated, the cable 32 has a circular cross-section and the opening formed by the two half-rings 311 and 312 is also circular and of a diameter slightly greater than that of the cross-section of the cable.

[0102] Once the support 20 is placed around the cable 32, the two half-rings 311 and 312 can be connected to each other for example by means of a hinge or ball joint 26, or be secured to each other for example by means of screws or nuts or other preferably removable fastening means.

[0103] Optionally, the support 20 can also be surrounded by electromagnetic shielding to prevent interference with the sensors from any surrounding sources of electromagnetic waves as well as from the Earth's permanent magnetic field. This shielding can be made, for example, of a specific steel.

[0104] Whether or not such shielding is present, the support 20 can also be equipped with one or more additional magnetic field sensors 37 adapted to measure, in particular, the Earth's magnetic field, in order to subtract its value when processing the values ​​of the magnetic field components measured by the magnetic field sensors 36. The additional sensor(s) 37 can be housed in the support 20, i.e., inside it and / or outside the support 20. At least one additional sensor 37 can be removable, for example, by being removablely inserted into or onto the support and thus being able to be disconnected and not used with the support 20.

[0105] Optionally, the support 20 may also include a communication device adapted to transmit data from at least one measuring device 36 and / or at least one device 11, 12 for processing these measurements to the outside.

[0106] The communication device may include one or more antennas.

[0107] Thus, an electrical cable arrangement according to the present invention comprises the cable 32 and at least one support 20 placed around the cable 32.

[0108] As shown in the particular embodiment of [Fig.4], the electrical cable arrangement can include a plurality of supports 20, placed around the cable 32 at predetermined intervals from each other.

[0109] The processing means 38 may be unique and common to all the media 20. Alternatively, a processing means 38 may be provided for each medium 20 and communication means adapted to communication between the various processing means 38 may optionally be provided.

[0110] In the particular embodiment illustrated, the supports 20 are all identical, each has five magnetic field sensors 36 and are arranged at regular intervals along the cable 32.

[0111] Such a configuration makes it possible to guarantee a measurement of the current intensities of high quality including in the case where the conductors 34 are twisted, for example due to manufacturing conditions and / or specific constraints, which could affect the sensitivity of the measurement of magnetic fields.

[0112] The number of supports 20 to be placed around the cable 32 and the distance between each support 20 are of course to be defined according to the type of cable 32 considered.

[0113] The invention can be applied to many types of cables, such as cables used in buildings, which are designed for voltages generally below 1000 V, and distribution cables, which are designed for voltages generally equal to or greater than 1000 V.

Claims

1. Demands Support (20) containing a measurement system for at least one parameter of an electrical cable (32), said support (20) being adapted to be positioned around said cable (32) in a removable manner, said measurement system comprising at least one device (36) for measuring said at least one parameter and at least one device (11, 12) for processing measurements of said at least one parameter, said at least one processing device (11, 12) being connected to said at least one measuring device (36); said support (20) being made in a first and a second part (21, 22) which each house at least one part of said at least one measuring device; said first and second parts (21, 22) of said support (20) each having a first end (210, 220) and a second end (230, 240), said first and second parts (21, 22) being assembled at their first end (210, 220) by means of a joint (26) along a first axis (z) of said support, said joint (26) making said first and second parts (21, 22) of said support (20) mobile around said first axis (z); - the said first and second parts (21, 22) of said support (20) each further housing at least one part of said at least one processing device (11, 12); - said support (20) further comprising at least one element for holding said at least one processing device (11, 12) in position relative to said support (20); said support (20) being characterized in that: - the said first and second parts (21, 22) of the said support (20) do not come into mutual contact in a region extending from the said joint (26) to the said second extremities (230, 240) inclusive, along a second axis (x) of the said support perpendicular to the said first axis (z); - said at least one measuring device (36) comprises at least one magnetic field sensor (36), said at least one parameter being the intensity of an instantaneous current flowing in said cable (32); - said at least one measurement processing device (11, 12) comprises two integrated circuit cards respectively housed in said first and second parts of the support (20) and said two integrated circuit cards are in mutual mechanical contact.

2. Support (20) according to claim 1, characterized in that said element for holding said at least one processing device (11, 12) in position relative to said support (20) is a locking clip.

3. Support (20) according to any one of the preceding claims, characterized in that said first and second parts (21, 22) are surrounded by electromagnetic shielding.

4. Support (20) according to any one of the preceding claims, characterized in that it further comprises at least one additional magnetic field sensor (37) adapted to measure the Earth's magnetic field.

5. Support (20) according to claim 4, characterized in that said at least one additional sensor (37) is housed in said support (20).

6. Support (20) according to claim 4, characterized in that said at least one additional sensor (37) is disposed on said support and outside said support.

7. Support (20) according to claim 4, 5 or 6, characterized in that said at least one additional sensor (37) is removable.

8. Support (20) according to any one of the preceding claims, characterized in that said joint (26) is a hinge.

9. Support (20) according to any one of claims 1 to 7, characterized in that said joint (26) is a ball joint.

10. Support (20) according to any one of the preceding claims, characterized in that said first and second parts (21, 22) are half-rings.

11. Support (20) according to any one of the preceding claims, characterized in that it further comprises a communication device adapted to transmit outwardly data from said at least one measuring device (36) and / or said at least one processing device (11, 12).

12. Support (20) according to the preceding claim, characterized in that said communication device comprises at least one antenna.

13. Electrical cable arrangement comprising an electrical cable (32) comprising a plurality of conductors (34), characterized in that it further comprises at least one support (20) according to any one of the preceding claims placed around said cable (32).

14. Electrical cable arrangement according to claim 13, characterized in that it comprises a plurality of supports (20) according to any one of claims 1 to 12, placed around said cable (32) at predetermined intervals from each other.

15. A method for measuring the current intensity in an electrical cable (32) comprising a plurality of conductors (34) by means of at least one measuring device (36) and at least one measurement processing device (11, 12), said at least one measuring device (36) and said at least one processing device (11, 12) being part of a support (20) according to any one of claims 1 to 12, said measuring device (36) comprising a plurality of magnetic field sensors (36), said method being characterized in that it consists of simultaneously measuring the current intensity in the conductors (34) of said plurality of conductors, by means of said at least one measuring device (36) and said at least one processing device (11, 12), by carrying out steps consisting of: placing (11) said plurality of magnetic field sensors (36) around said cable (32), in at least one location of said cable (32);measure (E2) simultaneously, for each of said conductors (34), at least one component of the magnetic field produced by the current flowing in said conductor (34), by means of said plurality of magnetic field sensors (36); for each of said conductors (34), determine (E3) the angle between said conductor and the nearest magnetic field sensor (36) of said plurality of magnetic field sensors, said angle being defined with respect to the center of said cable (32) and by assimilating said conductors (34) and said sensors (36) to points;the current intensities in said conductors (34) being linked to the components of the magnetic field measured by the relation B = kMI where B is the matrix of said components of the magnetic field, I is the matrix of said current intensities, M is a matrix comprising a plurality of proportionality coefficients depending on said angles between said conductors (34) and said magnetic field sensors (36) and k is a predetermined coefficient, calculate (E4) the inverse M 1 of the matrix M, so as to deduce the values ​​of said current intensities I =; (po / l^.M '.B, where po is an equivalent magnetic permeability which takes into account the presence of insulating materials in said cable, said at least one measurement processing device (11, 12) being adapted to receive the values ​​of said magnetic field components and to apply the steps (E3, E4) of angle determination and inverse matrix calculation to deduce the intensity of the current flowing in each of said conductors (34).

16. Method according to the preceding claim, characterized in that the measurement step (E2) consists of simultaneously measuring, for each of said conductors (34), the tangential component and the radial component of the magnetic field produced by the current flowing in said conductor (34), by means of said plurality of magnetic field sensors (36).

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