Method for monitoring the condition of at least one cable related to the operation of a wheel motor of a vehicle

Abstract

Title: Method for monitoring the condition of at least one cable connected to a wheel motor of a vehicle. This method comprises data acquisition, determining the resistance of at least one cable based on the acquired data, detecting a change in resistance, and determining a maintenance strategy to be applied when a change in the resistance of at least one cable is detected. No figure is provided for the abstract.

Description

Title of the invention: Method for monitoring the condition of at least one cable related to the operation of a wheel motor of a vehicle

[0001] The invention relates to a method for monitoring the condition of at least one cable connected to the operation of a wheel motor of a vehicle, such as an electrical connection cable or a data transmission cable relating to said motor. The invention also relates to a system for monitoring the condition of at least one cable connected to the operation of a wheel motor.

[0002] In the automotive industry, it is common practice to integrate wheel motors into electric or hybrid vehicles. Wheel motors are electrical machines whose stator assembly is fixed to the wheel carrier of at least one wheel, while the rotor is connected to a rim of that wheel. Specifically, the vehicle comprises a plurality of such wheel motors, for example, two or four. Each of these wheel motors is connected by at least one cable, or even a plurality of cables, for example, high- and / or low-voltage power supply cables as well as data transmission cables, for example, data relating to various measurements performed within the motor. Since these cables are connected to at least one moving part of the motor due to its connection to one of the wheels, they therefore comprise at least one dynamic loop.

[0003] Furthermore, the limited space within the vehicle may mean that some of the cables have a small radius of curvature and / or high dynamics. The various cables are then constantly deformed and subjected to stress, particularly in tension, torsion and / or bending, which can promote the progressive wear of said cables.

[0004] A progressive breakage of the internal strands forming the bundle of a cable can then be observed. When the number of active strands decreases, the thermal resistance of the damaged cables increases, leading to a loss of performance and a risk of overheating.

[0005] Also, a progressive degradation of the cable's electromagnetic insulation, also referred to as electromagnetic shielding, can be observed. Breakdown of the electromagnetic shielding is then likely to cause electromagnetic interference in the motor.

[0006] Thus, it is essential to implement diagnostic means capable of detecting damage to wheel motor cables.

[0007] The invention falls within this context and aims to provide a method and system for monitoring the condition of at least one cable related to the operation of a wheel motor capable of detecting damage to wheel motor cables and providing appropriate maintenance strategies.

[0008] The invention relates to a method for monitoring the condition of at least one cable connected to the operation of a wheel motor of a vehicle equipped with a plurality of wheel motors, each of said motors being connected by at least one cable. The method comprises: - a data acquisition step relating to at least two of an intensity, a power and a voltage of at least one electric current flowing in at least one cable connected to one of the wheel motors; - a step of determining at least one resistance of at least one cable on the basis of data acquired relating to at least one electric current and a step of detecting a variation of at least one resistance of said cable with respect to at least one reference value of the at least electrical resistance; - a step to determine a maintenance strategy to be applied when a variation in at least one electrical resistance of at least one cable is detected.

[0009] In particular, the data acquisition step includes the acquisition of data relating to at least one temperature, in particular an ambient temperature, the step of determining at least one resistance of at least one cable being carried out as a function of the at least one acquired temperature.

[0010] According to one embodiment of the method, the vehicle comprises a plurality of electrical circuits, at least one primary electrical circuit being configured to allow the flow of a primary electrical current in a bundle of at least one electrical cable and at least one secondary electrical circuit being configured to allow the flow of a secondary electrical current in an electromagnetic shield, surrounding the bundle, of at least one cable. The steps of data acquisition, determination of at least one resistance of said cable and detection of a variation in said resistance are then performed for at least one primary electrical current and / or at least one secondary electrical current.

[0011] Optionally, the step of determining a maintenance strategy includes a substep of determining a category of variation of at least one determined resistance selected from a plurality of categories of resistance variation each defined by at least one threshold of resistance variation.

[0012] Optionally, the method further comprises: - the recording of at least part of the acquired data and / or at least one determined resistance; and / or - the estimation of a future evolution of at least one resistance of at least one cable based on recorded data and / or an algorithm for learning the evolution of at least one resistance of at least one cable.

[0013] According to one example of implementation, the vehicle includes a control module for at least one component equipping the vehicle, the method further comprising a step of applying at least one defined maintenance strategy including the control of at least one component via the control module.

[0014] Optionally, the method further includes a step of emitting an information message, visual and / or audible, concerning the maintenance strategy to be applied.

[0015] The invention also relates to a monitoring system for at least one cable linked to the operation of a wheel motor of a vehicle, the system comprising hardware and / or software elements implementing the method according to the invention, the hardware elements comprising at least one data processing unit and a measuring device comprising a plurality of sensors.

[0016] Optionally, said system further comprises: - a junction box, common to a plurality of wheel motors, at least one battery, at least one sensor of the measuring device being located on the battery, on the junction box and / or on one of the wheel motors; and / or - a primary electrical circuit configured to allow the flow of a primary electric current within a bundle of at least one cable and / or a secondary electrical circuit configured to allow the flow of a secondary electric current through an electromagnetic shield of at least one cable.

[0017] The invention also relates to a motor vehicle comprising the monitoring system according to the invention.

[0018] The invention can be extended to a computer program product comprising program code instructions recorded on a computer-readable medium to implement the steps of the process according to the invention when said program is running on a computer or a computer program product downloadable from a communication network and / or recorded on a computer-readable and / or computer-executable data medium, comprising instructions which, when the program is executed by the computer, cause the computer to implement the process according to the invention.

[0019] The invention can finally be extended to a computer-readable data recording medium on which is recorded a computer program comprising program code instructions for implementing the method according to the invention or a computer-readable recording medium comprising instructions which, when executed by a computer, lead the latter to implement the method according to the invention.

[0020] Other details, features and advantages will become clearer upon reading the detailed description given below, by way of example and not limitation, in relation to the various embodiments illustrated in the following figures:

[0021] Fig. 1 is a schematic view of an embodiment of a system for monitoring the condition of at least one cable of a vehicle, in particular a cable connected to the operation of a wheel motor of the vehicle.

[0022] Figure 2 is a general flowchart of an example of the execution of a process of monitoring the condition of at least one cable of the vehicle, including a cable connected to the operation of a wheel motor of the vehicle.

[0023] Fig. 3 is a schematic representation of a first example of positioning sensors of a measuring device in the vehicle.

[0024] Figure 4 is a schematic representation of a second example of positioning of sensors of the measuring device in the vehicle.

[0025] Fig. 5 is a schematic representation of a third example of sensor positioning of the measuring device in the vehicle.

[0026] Fig. 6 is a schematic representation of a fourth example of sensor positioning of the measuring device in the vehicle.

[0027] Figure 7 is a schematic representation of a fifth example of positioning of sensors of the measuring device in the vehicle.

[0028] Figure 1 schematically illustrates an embodiment of a motor vehicle 1, in particular a vehicle 1 comprising at least one electric wheel motor. Specifically, the vehicle 1 according to the invention comprises a plurality of electric wheel motors 2, i.e., motors each comprising a stator element mounted, for example, on a wheel hub of the vehicle 1 and a rotor connected, for example, to a wheel rim of the vehicle 1. The wheel motor 2 is thus capable of directly driving the wheel, without requiring intermediate transmission elements, and is partially integrated into the wheel. Optionally, electronic components, particularly power electronics, of the wheel motor are mounted on the body of the vehicle 1 and / or the wheel hub of the wheel in question. Optionally, a reduction gear, not shown, may be integrated into one of the wheels in question, between the wheel motor 2 and the rim of said wheel.As further explained below, vehicle 1 comprises at least one pair of wheel motors 2, for example two or four wheel motors 2, said motors being arranged on a pair of front wheels and / or a pair of rear wheels of vehicle 1. Vehicle 1 is thus either electric or hybrid. Vehicle 1 is, for example, a passenger car, a commercial vehicle, a truck, or a bus. Optionally, vehicle 1 is a connected vehicle or an autonomous vehicle.

[0029] The various wheel motors 2 are each connected by at least one cable 21. In particular, each wheel motor 2 is connected to a plurality of cables 21, including low- and / or high-voltage electrical connection cables 21, related to its operation. For example, such cables 21 are intended for supplying electrical energy or, without limitation, data transmission. The cables 21 are thus connected on the one hand to a fixed element, such as a vehicle battery 3 mounted on the vehicle body, and on the other hand to a moving element, namely the wheel motor 2. For example, the cables 21 extend at least between a mounting point located on one of the wheel motors 2 and a mounting point located, without limitation, on a portion of the vehicle body 1, on the vehicle battery 3, and / or on a junction box 4 of the vehicle 1, as described below. Each cable 21 thus includes a dynamic loop, meaning that a portion of the cable 21 can move and deflect in the vicinity of one of the wheels.

[0030] Throughout the description below, the terms "primary", "secondary", "first" or "second" are intended to distinguish similar elements or principles and not to define a hierarchy.

[0031] The vehicle 1 includes a monitoring system 10 for the condition of at least one cable 21, configured to detect wear or failure in at least one of the cables 21 connected to at least one of the wheel motors 2 of the vehicle 1. Advantageously, the monitoring system 10 is also capable of providing maintenance strategies adapted as needed. The vehicle 1, in particular the monitoring system 10, includes hardware and / or software components capable of implementing a method for monitoring the condition of at least one cable 21 of the vehicle 1 connected to one of the wheel motors 2 as described below. These hardware components include at least one data processing unit 5 and a measuring device 6. Optionally, the monitoring system 10 further includes a control module 7 capable of controlling at least one component of the vehicle 1 and / or an alert module 8.

[0032] The measuring device 6 comprises a plurality of sensors 61 capable of measuring at least one of the following: current intensity, power, and / or voltage. Additionally, optionally, at least one sensor 61 is capable of measuring at least one temperature, in particular the temperature of at least one cable 21, the surface temperature of the cable 21, and / or an ambient temperature, for example, in the vicinity of said cable 21. In particular, the sensors 61 are arranged so as to frame dynamic loops specific to all or part of the various cables 21 of each wheel motor 2, that is to say, they are arranged on either side of said loops. A pair of sensors 61 is thus associated with one or more dynamic loop(s), one of the sensors 61 being arranged upstream of the loop(s) and the other downstream. Note that the same sensor 61 can be common to a plurality of cables 21, and by extension to a plurality of dynamic loops.

[0033] For example, as illustrated in Figures 3 to 7, the sensors 61 are arranged at the level of the battery 3 of the vehicle 1, one of the wheel motors 2, the body of the vehicle 1 and / or at least one junction box 4 to which cables 21 specific to different The wheel motors 2 are connected. According to an embodiment illustrated in [Fig. 3] or 6, the sensors 61 of a pair of sensors 61 are arranged on the battery 3 so as to frame two dynamic loops specific to an associated forward and return cable 21. A similar principle can be applied when the cables are connected to a junction box 4, as shown in [Fig. 4] or 5. According to yet another example, one of the sensors 61 of the pair is arranged on the battery 3 or the junction box 4, while the other is arranged at the wheel motor 2, as shown in [Fig. 7]. It is understood that the different sensor positions indicated above are given by way of example and can be combined; different positions can be applied to different wheel motors 2 within the vehicle 1.

[0034] The processing unit 5 is capable of receiving data from the measuring device 6. It comprises at least one computer with hardware and software resources, more specifically at least one processor or microprocessor, capable of processing said data and executing instructions for the implementation of a computer program. The processing unit 5 includes, or cooperates with, memory elements of the management system or of the vehicle 1. In particular, the processing unit 5 includes a CAN (Controller Area Network) data bus and / or other data bus.

[0035] The control module 7 is configured to receive instructions from the processing unit 5 and to control various components of the vehicle 1 in order to apply a maintenance strategy, such as the wheel motors 2 of the vehicle 1, for example to prevent the vehicle 1 from starting, and / or a Human-Machine interface, including for example a screen, in particular to issue an alert to the driver.

[0036] The alert module 8 is capable of disseminating information, in particular an audio and / or visual message, to a user. For example, the alert module 8 includes the Human-Machine Interface.

[0037] An embodiment of a method for monitoring the status of at least one cable 21 of the vehicle 1 connected to the operation of at least one wheel motor 2 is described below. Such a method can also be considered equivalent to a method for operating the monitoring system 10 equipping the vehicle 1 or for operating the vehicle 1 according to the invention. For clarity, the following description is given with reference to one of the cables 21; however, it is understood that this description applies to all or part of the cables 21 connected to the wheel motors 2 and / or linked to the operation of at least one of the wheel motors 2, the different steps being carried out simultaneously or successively for the different cables 21.

[0038] The monitoring method 100 comprises, initially, a data acquisition step E01 relating to at least two of an intensity Icx, an power Pcx and a voltage Ucx of at least one electric current flowing in at least one cable 21 connected to one of the wheel motors 2 via the measuring device 6 described above. Note that the acquisition of said data can be carried out by direct measurement, via the measuring device 6, and / or by estimation by the processing unit 5 from measurements carried out by the measuring device 6. In particular, said data is acquired by detecting the operation of at least one of the wheel motors 2 and / or its control conditions.

[0039] Optionally but preferably, the data acquisition step E01 further includes the acquisition of data relating to a temperature Tcx as indicated above, in particular an ambient temperature Tcx.

[0040] In particular, the acquisition step E01 includes the acquisition of data relating to electrical currents applied in all or part of the cables 21 connected to the wheel motors 2, in particular for all or part of the cables 21 comprising a dynamic loop, or even for each of the cables 21 connected to one of the wheel motors comprising a dynamic loop.

[0041] The measuring device 6 of the monitoring system 10 is thus capable of measuring and / or estimating in real time or at regular time intervals data specific to one or more of the cables 21 when at least one electric current flows through them, in particular by detecting the operation of at least one of the wheel motors 2 and the control conditions thereof.

[0042] According to a particular embodiment of the method according to the invention, the vehicle 1 comprises a plurality of electrical circuits capable of allowing the circulation of distinct, identifiable electrical currents at different portions of at least one cable 21 in order to allow the detection and localization of damage to at least one cable 21 within it.

[0043] Indeed, in a known manner, the at least one cable 21 comprises a plurality of internal current-conducting strands, in particular made of a metallic material, forming a bundle. When said strands are damaged and break, the reduction in the number of active internal strands forming the bundle and capable of allowing the flow of electric current leads to an increase in the resistance of the at least one cable 21, accompanied by a loss of performance and a risk of overheating.

[0044] Also, at least one cable 21 conventionally includes electromagnetic shielding comprising, in particular, a sheath of plastic or rubber material surrounding the bundle of internal strands and a foil or at least one metallic wire, for example of aluminum or copper, capable of conducting an electric current. Degradation of the electromagnetic insulation of the cable is likely to cause electromagnetic interference with the motor.

[0045] Also, in order to identify whether damage is located in the bundle of at least one cable 21 or in its shielding, the method according to the invention can advantageously be carried out so as to allow the flow of a primary electric current Cx1 within a primary electrical circuit comprising the bundle, in particular the internal strands of the bundle of cable 21, of at least one cable, and / or the flow of a secondary electric current Cx2 through a secondary electrical circuit comprising the electromagnetic shielding of at least one cable 21 at a given time t. Each of said circuits includes a common or separate power supply. Two separate electric currents can then flow separately in the at least one cable, simultaneously or at separate times.

[0046] The data acquisition step E01 as described above then optionally includes the acquisition of data for the different electric currents implemented in the at least one cable 21, and in particular through the electromagnetic shielding and / or the bundle of said cables 21. Such a principle can be applied to all or part of the cables 21 connected to the wheel motors 2. It should be noted that the measurements carried out for the primary electric current Cxl and the secondary electric current Cx2 are then preferably carried out by sensors 61 separate from the measuring device 6 associated with the dynamic loop of the at least one cable.

[0047] Also, the primary electric current Cxl and the secondary electric current Cx2 can flow in at least one cable 21, that is, in one of the cables 21 considered, at the same instant t or at distinct periods. For example, without limitation, the primary electric current Cxl corresponds to an electric current flowing in at least one of the wheel motors 2 when the vehicle 1 is in motion, capable of supplying said motor with electrical energy. Alternatively or additionally, the primary electric current Cxl is an electric current emitted through the at least one cable 21 solely for diagnostic purposes, to monitor the condition of said cable 21. Such a current can then be emitted when the vehicle 1, and the wheel motors 2, are stationary, when the wheel motor 2 is starting, when the wheel motor 2 is stopping, or at any other defined instant.

[0048] Similarly, according to a preferred embodiment, the secondary electric current Cx2 is an electric current emitted through at least one cable 21 solely for diagnostic purposes, monitoring the condition of said cable, when the vehicle 1 is at rest, for example at the start of the wheel motor 2, at the stop of the wheel motor 2 or any other defined instant.

[0049] Also, the acquisition of E01 data relating to at least one cable 21 and / or different portions of said cable 21 can be implemented continuously, in real time, or at predetermined time intervals. The same applies to the implementation primary electrical currents Cxl and secondary electrical currents Cx2 when these only have a diagnostic function.

[0050] As indicated above, when a measurement of the current Icx, voltage Ucx and / or power Pcx cannot be performed, the acquired data are optionally estimated for at least one electric current. This principle also extends to the primary electric current Cx1 and / or the secondary electric current Cx2.

[0051] The method 100 according to the invention then comprises a step E02 of determining at least one resistance Rcx of at least one cable 21 based on data acquired relating to at least one electric current. In particular, the at least one resistance Rcx determined is the resistance of at least the portion of the cable 21 comprising the dynamic loop specific to said cable 21. In this case, the resistance determined is that of the portion of cable 21 located between a pair of sensors 61 of the measuring device 6. Such a principle can be extended to all or part of the plurality of cables 21.

[0052] Conventionally, the at least one resistance Rcx is determined by the processing unit 5 from the acquired intensity data Icx of the at least one electric current as well as from the power data Pcx and / or voltage data Ucx of this same current on the basis of the following formulas: Ucx^

[0054] and / or

[0055] Pcx-Rcx x(lcx)2

[0056] Where: Ucx is the voltage of at least one electric current flowing through at least one cable 21 considered; Rcx is the estimated resistance of at least one cable 21 considered; Icx is the intensity of at least one electric current flowing through at least one cable 21 considered; Pcx is the power of at least one electric current flowing through at least one cable 21 considered.

[0057] Optionally, at least one resistance Rcx of at least one cable 21 is determined based on previously acquired temperature data Tcx, in particular the ambient temperature Tcx. The temperature is then taken into account to correct the estimated, theoretical resistance Rcx of the cable 21.

[0058] Rcx -R0 x (1 + aO x Tcx)

[0059] Where:

[0060] Rcx is the effective resistance, in ohms, of at least one cable 21 considered, estimated, at the measured temperature;

[0061] RO is the resistance in ohms at a temperature of 0°C;

[0062] aO is a temperature coefficient in Kelvins to the power minus one (K1), for example equal to 3.9 x 10³ K1 for copper at 0°C and 3.7 x 10³ K

[0063] Tcx is at least one previously determined effective temperature, in degrees Celsius.

[0064] The determination of at least one resistance Rcx of at least one cable 21 applies mutatis mutandis to the determination of a primary resistance Rcxl specific to the bundle of internal strands of at least one cable 21, determined from data acquired on the basis of the primary electric current Cxl flowing in said cable 21 and / or to the determination of a secondary resistance Rcx2 specific to the shielding of at least one cable 21, determined from data acquired on the basis of the secondary electric current Cx2 flowing in said cable 21. Such a principle can be applied to the different cables 21.

[0065] The method then includes a step of detecting a variation E03 in the resistance Rcx of at least one cable 21. The detection of such a variation is, for example, carried out over time. To this end, it includes comparing the previously calculated resistance Rcx for at least one cable 21 with at least one reference value Rfcx of the resistance of said cable 21. A variation ARx is thus detected when the value of the calculated or estimated resistance Rcx differs from said reference resistance value Rfcx, i.e., when the value of the variation ARx is non-zero. The reference value Rfcx may be a previous resistance value determined at a time tx, in particular during a previous implementation of the method according to the invention.Additionally or alternatively, the reference value of at least one resistance Rfcx is a resistance value entered or recorded on one of the memory elements, for example recorded in a table as a function of current values ​​Icx, voltage Ucx and / or power Pcx of an electric current corresponding to values ​​estimated or measured at the installation of the wheel motors 2.

[0066] It should be noted that such detection of a variation ARx of at least one resistance Rcx can be applied mutatis mutandis to different portions of the cable 21 as described above, in particular so as to detect a variation ARx of the secondary resistance Rcx2 determined for the shielding of said cable 21 and / or of the primary resistance Rcxl of the bundle of internal strands of said cable 21 at a given instant. Each of said resistances of at least one cable 21 is then compared to a reference resistance value Rfcx specific to it, the latter being defined as described above.

[0067] The method then includes, when a variation ARx of the resistance Rcx of at least one cable 21 is detected, a step E04 for determining a maintenance strategy to be applied based on the magnitude of the detected variation ARx of electrical resistance. Such a step is performed as soon as a variation ARx is detected for one of the cables 21 of the plurality of cables 21 connected to at least one of the wheel motors 2. Similarly, such a step is performed as soon as a variation ARx of one of the resistances is detected when, for a given cable 21, the variation ARx of the primary resistance Rcxl and / or the secondary resistance Rcx2 is evaluated.

[0068] By way of non-limiting example, the maintenance strategy to be applied depending on the magnitude of the variation ARx of at least one electrical resistance Rcx of at least one cable 21 detected includes at least one of the following: - the forecast of maintenance within a defined time and / or mileage, in particular estimated or calculated from predefined algorithms; - the expectation of immediate maintenance; - the limitation of the functions of vehicle 1; - the programmed stopping and immobilization of vehicle 1 within a defined time and / or mileage; - immobilizing vehicle 1 to prevent it from starting; and / or - immobilization of vehicle 1 even after restarting.

[0069] In particular, and optionally, the method 100 includes a step E05 of transmitting an informational message, visual and / or audible, to the user regarding the maintenance strategy to be applied. For example, such a message is transmitted via the Human-Machine Interface. Advantageously, such a message informs the user of the planned maintenance strategy, enabling them to understand and anticipate it.

[0070] Optionally but preferably, the determination of a maintenance strategy to be applied includes a substep E041 for determining a variation category ARx of at least one specified resistance Rcx selected from a plurality of variation categories ARx of said electrical resistance. In particular, said categories make it possible to distinguish different levels of importance of the variation ARx of at least one electrical resistance Rcx of at least one cable 21, each defined by at least one variation threshold ARx of at least one electrical resistance Rcx, and / or different types of damage to at least one cable 21, in particular so as to distinguish damage localized at the bundle level from damage localized at the electromagnetic shield level. In other words, the different categories make it possible, for example, to distinguish an variation ARx of at least one resistance resulting from damage of electromagnetic shielding or beam, of damage to electromagnetic shielding and beam, and different degrees of damage for each of these types of damage.

[0071] Determining the maintenance strategy to be applied then involves extracting E042 at least one predefined maintenance strategy associated with the ARx variation category of the at least one electrical resistance Rcx to which the calculated electrical resistance Rcx belongs. The maintenance strategies are thus, for example, associated by degree of urgency with the ARx variation categories of the at least one electrical resistance Rcx of the at least one cable 21, depending on the magnitude of said variation. By way of non-limiting example, a low-urgency maintenance strategy, such as a strategy providing for maintenance within a defined time or mileage interval, is associated with a low ARx variation of the at least one electrical resistance Rcx.Conversely, a high-urgency maintenance strategy, such as one involving immobilization of vehicle 1, is associated with a large variation ARx of at least one electrical resistance Rcx.

[0072] Such a principle extends to a plurality of cables 21, wheel motors 2 and / or applied electric currents, in particular when the primary electric current Cxl and / or the secondary electric current Cx2 are implemented, depending on the time t at which the method according to the invention is applied.

[0073] Optionally, but preferably, the method according to the invention further comprises a step of applying the maintenance strategy defined E06, including controlling at least one component of vehicle 1 via the control unit according to the defined maintenance strategy. By way of non-limitation, the component in question may be the human-machine interface, for example, for the purpose of disseminating a warning message or maintenance reminders, a driver assistance system, for example, to limit the speed of vehicle 1 and / or the wheel motors 2 of vehicle 1, or other, in order to immobilize vehicle 1 or prevent it from starting.

[0074] Optionally but preferably, the method according to the invention further comprises recording E07 at least a portion of the acquired, estimated, and / or calculated data. In particular, the method according to the invention comprises recording E07 at least a portion of the data relating to at least one determined electrical resistance on the memory elements. Additionally or alternatively, a strategy determined on the basis of said data is recorded. The information thus recorded can then be used subsequently, as described above, for the purposes of comparison and determination of the variation ARx of at least one electrical resistance Rcx of at least one cable 21.

[0075] Additionally or alternatively, the method further includes a step of estimating a future evolution E08 of at least one electrical resistance Rcx of at least one cable 21. Such an estimation can be performed from recorded data and / or from predefined algorithms. Optionally, the processing unit 5 is capable of learning the evolution of at least one electrical resistance of at least one cable 21 based on recorded data and / or entered or received data, for example, data from a database or server relating to vehicles of similar or different models, and / or based on vehicle usage conditions, such as temperature or other factors. Also, the processing unit 5 is capable of learning an optimal maintenance strategy based on recorded data.

[0076] Optionally, the estimation of the future evolution of at least one electrical resistance Rcx of at least one cable 21 specific to each wheel motor 2 is defined as a function of driving characteristics of at least one user, entered, measured and / or learned by the monitoring system 10. For example, such characteristics are related to a preferred driving mode, such as a "sport", "comfort", "eco" or other driving mode selected from known driving modes applicable to the vehicle 1.

[0077] Optionally, such an estimation of the future evolution of at least one electrical resistance Rcx takes into account a programmed route for vehicle 1 and / or a location of vehicle 1, for example, defined in a location device. The location device may, in particular, allow the location of vehicle 1 within the road infrastructure. It incorporates, for example, an approximate location system for vehicle 1 and / or a high-definition map of the road infrastructure. Specifically, the approximate location of vehicle 1 may be provided by a GPS-type system (Global Positioning System) that allows the extraction, from a mapping database, of information concerning the road infrastructure around the approximate position of vehicle 1. Alternatively or in addition, the location device may be a location system embedded in vehicle 1.

[0078] The invention thus proposes a method for monitoring the condition of at least one cable connected to a wheel motor of a vehicle, so as to enable the detection of wear on said cable and to provide an appropriate maintenance strategy. The invention thus ensures safer operation of vehicles using wheel motor-type electric motors. Furthermore, the proposed solution is low-cost and easily implemented on existing vehicles.

[0079] However, the present invention is not limited to the means and configurations described and illustrated herein, and also extends to any means or configuration equivalents and to any technically operative combination of such means insofar as they ultimately fulfill the functionalities described and illustrated in this document.

Claims

Demands

1. Method for monitoring (100) the condition of at least one cable related to the operation of a wheel motor of a vehicle (1) equipped with a plurality of wheel motors (2), each of said motors being connected by at least one cable (21), the method comprising: - a data acquisition step (E01) relating to at least two of an intensity (Icx), a power (Pcx) and a voltage (Ucx) of at least one electric current flowing in the at least one cable (21) connected to one of the wheel motors (2); - a determination step (E02) of at least one resistance (Rcx) of at least one cable (21) on the basis of data acquired relating to at least one electric current and a detection step (E03) of a variation (ARx) of at least one resistance of said cable (21) with respect to at least one reference value of the at least electrical resistance (Rfcx);- a determination step (E04) of a maintenance strategy to be applied when a variation (ARx) of at least one electrical resistance (Rcx) of at least one cable (21) is detected.;

2. A monitoring method (100) according to the preceding claim, wherein the data acquisition step (E01) includes the acquisition of data relating to at least one temperature, in particular an ambient temperature, the determination step (E02) of at least one resistance (Rcx) of at least one cable (21) being carried out as a function of the at least one acquired temperature.

3. A monitoring method (100) according to any one of the preceding claims, wherein the vehicle (1) comprises a plurality of electrical circuits, at least one primary electrical circuit being configured to allow the flow of a primary electrical current (Cxl) in a bundle of at least one electrical cable (21) and at least one secondary electrical circuit being configured to allow the flow of a secondary electrical current (Cx2) in an electromagnetic shield, surrounding the bundle, of at least one cable (21), the steps of data acquisition (E01), determination (E02) of at least one resistance (Rcx) of said cable (21) and detection (E03) of a variation (ARx) of said resistance (Rcx) being performed for at least one primary electrical current (Cxl) and / or at least one secondary electrical current (Cx2).

4. Monitoring method (100) according to any one of the preceding claims, wherein the determination step (E04) of a maintenance strategy includes a sub-step of determination (E041) of a variation category (ARx) of at least one determined resistance selected from a plurality of variation categories (ARx) of resistance each defined by at least one resistance variation threshold.

5. A monitoring method (100) according to any one of the preceding claims, comprising: - recording (E07) at least a part of the acquired data and / or at least one determined resistance (Rcx); and / or - estimating a future evolution of at least one resistance of at least one cable (21) as a function of recorded data and / or a learning algorithm of the evolution of at least one resistance of at least one cable.

6. A monitoring method (100) according to any one of the preceding claims, wherein the vehicle (1) comprises a control module (7) for at least one component equipping the vehicle (1), the method further comprising an application step (E06) of at least one defined maintenance strategy comprising the control of at least one component via the control module (7).

7. A monitoring method (100) according to any one of the preceding claims, further comprising a step of emitting (E05) an information message, visual and / or audible, concerning the maintenance strategy to be applied.

8. Monitoring system (10) of at least one cable related to the operation of a wheel motor (2) of a vehicle (1), the system comprising hardware and / or software elements implementing the method according to any one of claims 1 to 7, the hardware elements comprising at least one data processing unit (5) and a measuring device (6) comprising a plurality of sensors (61).

9. A vehicle (1) monitoring system (10) according to the preceding claim, further comprising: - a junction box (4), common to a plurality of wheel motors (2), at least one battery (3), at least one sensor (61) of the measuring device (6) being disposed on the battery (3), on the junction box (4) and / or on one of the wheel motors (2); and / or

10. - a primary electrical circuit configured to allow the flow of a primary electric current (Cxl) within a bundle of at least one cable (21) and / or a secondary electrical circuit configured to allow the flow of a secondary electric current (Cx2) through an electromagnetic shield of at least one cable (21). Motor vehicle (1) comprising the monitoring system according to claim 8 or 9.

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