Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/08—Locating faults in cables, transmission lines, or networks
  • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
  • G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
  • G01R31/58—Testing of lines, cables or conductors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
  • G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
  • G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
  • G01N27/83—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
  • G01R31/58—Testing of lines, cables or conductors
  • G01R31/59—Testing of lines, cables or conductors while the cable continuously passes the testing apparatus, e.g. during manufacture
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/0011—Arrangements or instruments for measuring magnetic variables comprising means, e.g. flux concentrators, flux guides, for guiding or concentrating the magnetic flux, e.g. to the magnetic sensor
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
  • G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
  • G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
  • G01R33/07—Hall effect devices
  • G01R33/072—Constructional adaptation of the sensor to specific applications
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G1/00—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines

Definitions

• the present application relates to the field of devices and methods making it possible to detect and locate one or more defects in components comprising at least one ferromagnetic part, and more particularly concerns a magnetic probe for detecting defects in cables comprising a ferromagnetic part.
• a magnetic probe for detecting defects in a ferromagnetic portion of a cable.
• the magnetic probe includes a frame, at least three magnetic circuits, and at least three magnetic sensors.
• the frame has a central axis and a passage for passing the cable through.
• the at least three magnetic circuits are held by the frame, spaced apart from each other. others.
• Each circuit includes a core configured to extend along the cable when the probe is in use (ie, at least one side of the core is substantially parallel to the cable); means for generating a magnetic flux in a section of the ferromagnetic part of the cable; and an air gap located in the core to create a point of zero magnetic field surrounded by a region of low magnetic field, between the core and the central axis.
• Each magnetic sensor is associated with at least one of the at least three magnetic circuits and is located outside the core, in the low magnetic field region.
• the at least three magnetic sensors are capable of measuring a low magnetic flux or a low variation in the magnetic flux caused by defects in the ferromagnetic part of the cable.
• the magnetic probe includes exactly three magnetic circuits and three associated magnetic sensors equidistant from each other.
• two adjacent magnetic circuits are spaced 120° apart around the central axis of the frame.
• the core includes a longitudinal portion extending along the cable, when the probe is in use, and two legs oriented radially toward the central axis; and the means for generating the flux include a first magnet located in a first leg of the two legs and a second magnet located in a second leg of the two legs.
• the magnetic flux generated in the cable is below a magnetic saturation level of the cable when the magnetic probe is in use.
• the air gap of each circuit creates, produces or generates a magnetic field leak in the vicinity thereof and creates a point of zero magnetic field surrounded by an area of weak magnetic field.
• the at least three magnetic sensors are ultrasensitive sensors.
• the at least three magnetic sensors are sensors capable of measuring a magnetic flux of less than 5 mT.
• the at least three magnetic sensors each have an operating range of ⁇ 2.5 mT, and preferably an operating range of at least ⁇ 1 mT.
• the magnetic probe includes one or more control modules, each including acquisition means, processing means and calculation means for acquiring and processing signals captured by the at least three magnetic sensors, and to carry out calculations from the processed signals.
• each control module includes algorithmic means for reducing or eliminating the effect of a magnetic field generated by a current circulating in the cable under inspection, the cable corresponding in this case to an electrical conductor energized by a high voltage transmission line.
• a magnetic field originating from the cable or parasitic is an alternating magnetic field and the algorithmic means for reducing or eliminating the effect of the alternating magnetic field generated by a current flowing in the cable under inspection includes an algorithm for filtering a component at the frequency of a measured signal or to synchronize the reading times of flux measurements with the times when the current circulating in the conductor passes through zero.
• the magnetic probe includes a sensor of the Earth's gravitational field, each control module including algorithmic means making it possible to reduce or eliminate the effect of the Earth's gravitational field on the magnetic flux measurements made by the sensors.
• an opening of the magnetic probe corresponds to a transverse circular section around the central axis capable of receiving the cable between the at least three magnetic sensors of the magnetic probe, the ratio of the radius of the opening of the magnetic probe on the weight of the magnetic probe being of the order of 60 mm/kg. It should be noted that the opening is the circular section in the center of the magnetic probe 20, around the central axis, where the cable 22 will be located during inspection.
• the at least three magnetic circuits and the at least three magnetic sensors are positioned and dimensioned to allow the inspection of connection sleeves of electrical conductors on high voltage transmission lines, the ferromagnetic part including a section in the sleeves connecting the electrical conductors, and a transition zone between the conductors and the sleeves, in which the measurement of the magnetic probe allows the cable to be inserted into the probe and in which the opening of the magnetic probe allows a grip continuous measurement during relative movement between the magnetic probe and the sleeve.
• the frame, the at least three magnetic circuits and the at least three sensors have a total mass of less than 2 kg, making the magnetic probe portable by drone or similar means of transportation.
• the configuration of the passage in the frame allows the probe to be installed on a cable, by drone, without human intervention.
• the at least three magnetic sensors are of the “fluxgate”, Hall effect or magnetoresistance type.
• the measurements carried out by the at least three magnetic sensors have a linear relationship with a geometric parameter of the ferromagnetic part of the cable, facilitating the calibration of the magnetic probe.
• the passage includes a fixed, permanently open gap.
• the core and the legs each include a stack of mild steel strips.
• a method for detecting defects of a ferromagnetic portion of a cable uses the magnetic probe as defined previously.
• a system for detecting defects of a ferromagnetic portion of a cable includes a magnetic probe as defined above and transport means making it possible to move the magnetic probe along the cable so as to collect measurements representative of potential defects in the ferromagnetic part of the cable.
• Figure 1 illustrates continuous poles made of mild steel, and comprising magnets with a strong magnetic field to create a magnetic field.
• Figure 2 is a representation of the “magnetester” device.
• Figure 3 illustrates an example of a conductor.
• Figure 4 illustrates an air gap in a magnetic circuit to create a point of zero magnetic field, in accordance with one embodiment.
• Figure 5 is a side view of a magnetic probe, consistent with one embodiment.
• Figure 6 is a front view of the magnetic probe of Figure 5.
• Figure 7 is an example of a magnetic sensor, in accordance with one embodiment.
• Figure 9 illustrates a magnetic probe, in accordance with one embodiment.
• Figure 10 illustrates a perspective view of the magnetic probe shown in Figure 8.
• Figure 11 illustrates a side view of the magnetic probe shown in Figure 9.
• Figure 12 illustrates a top view of the magnetic probe shown in Figure 9.
• Figure 13 illustrates the magnetic probe shown in Figure 9, into which a cable has been inserted.
• Figure 14 illustrates the ability of the magnetic probe to compensate for frame movement.
• FIGS 15 to 25 illustrate different results obtained with the magnetic probe.
• defects as well as any similar or equivalent expression, will be used in the context of this disclosure to refer to certain types of loss of material or physical integrity in ferromagnetic materials, such as losses steel section (“LMA”), broken steel strands (“LF”) and broken electrical conductor connection sleeves (such as ACSR type electrical conductors).
• LMA losses steel section
• LF broken steel strands
• ACSR ACSR type electrical conductors
• a signal represents a variation of any physical quantity.
• a signal can be analog or digital, and typically carries information.
• a signal can be continuous or discrete and have different characteristics such as, for example and without limitation, a period, an amplitude and a phase.
• an electrical signal can be representative of a potential difference, the intensity of an electric current, the variation in amplitude, the variation of a frequency, the variation of a phase and/or any other relevant physical quantity. It should be noted that the properties of a signal can be measured and during a measurement, a sample represented by a set of data is obtained. The data set is generally representative of the measured signal.
• the “measurement time” represents the duration, generally finished, the acquisition of a sample comprising a set of data. Following its acquisition, the signal (or the sample comprising a set of data representative of the signal) can be processed.
• the “processing” of a signal typically includes a method, a procedure and/or the use of technique(s) making it possible to confirm the presence (or absence) of faults, to locate the location of one or more faults where applicable, and/or to reveal certain physical characteristics relevant to the characterization of these defects.
• the processing of a signal may include operations or a series of mathematical operations.
• signal processing typically makes it possible to obtain a property of a signal which can subsequently be associated with a physical quantity or with the variation thereof, which can in turn be associated with the presence or absence of defects in the ferromagnetic part of the inspected cable.
• Frine resolution will mean that the resolution is less than 1 pT;
• Low offset (or “offset”) will mean an offset of less than 10 pT;
• Low noise level will mean that the spectral density of the noise is less than 10 nT/Hz;
• the apparatus(es), method(s) and system(s) described herein, or at least elements thereof, may be implemented in computer programs executed on programmable computers (eg, a microcontroller), each comprising at least one processor, a data storage system comprising, for example and without limitation, volatile and non-volatile memory elements, at least one input device and at least one output device.
• the programmable computer may be a programmable logic unit, a mainframe, a server and a personal computer, a cloud computing system, a laptop computer, a personal data assistant, a cellular telephone, a telephone smart device, portable device, tablet, smart display device, set-top box or virtual reality device.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=89979615

Family Applications (1)

Country Status (3)

Family Cites Families (4)

• 2022
  • 2022-08-24 CA CA3171364A patent/CA3171364A1/fr active Pending
• 2023
  • 2023-08-24 WO PCT/CA2023/051119 patent/WO2024040349A1/fr not_active Ceased
  • 2023-08-24 CA CA3265338A patent/CA3265338A1/en active Pending
  • 2023-08-24 EP EP23855938.9A patent/EP4577841A1/de active Pending

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