SYSTEM FOR CONTROLLING THE RECHARGE CURRENT OF A RAILWAY VEHICLE'S TRACTION BATTERY AND ASSOCIATED METHOD

Abstract

SYSTEM FOR CONTROLLING THE CHARGING CURRENT OF A RAILWAY VEHICLE'S TRACTION BATTERY AND ASSOCIATED METHOD The invention relates to a method for controlling the charging current of a traction battery of a railway vehicle, said method being characterized in that it comprises: a step E1 of acquiring a plurality of images of a pantograph mounted on said locomotive, at least one image of which is a thermographic image of said pantograph; a step E2 of identifying a pantograph-catenary contact zone from at least one acquired image of a pantograph; a step E3 of measuring the temperature of the identified pantograph-catenary contact zone from said thermographic image, to obtain a first temperature, called the measured temperature, corresponding to the representative temperature of at least one point of the identified pantograph-catenary contact zone.step E4 of controlling the charging intensity of a traction battery as a function of said measured temperature. Figure for the abbreviation: figure 2,

Description

Title of the invention: SYSTEM FOR CONTROLLING THE CHARGING CURRENT OF A TRACTION BATTERY OF A RAILROAD VEHICLE AND ASSOCIATED METHOD Technical field of the invention

[0001] The invention relates to the railway field and more particularly to the recharging of electric batteries in railway vehicles with traction batteries from the overhead lines. The invention further relates to a method and a system for controlling the intensity of such recharging. Technological background

[0002] Faced with current climate challenges, the issue of decarbonizing passenger transport is a top priority. In this regard, stakeholders in the rail sector are currently developing the first rail vehicles equipped with traction batteries to replace conventional diesel-powered rail vehicles on non-electrified lines.

[0003] A railway vehicle, such as a train, generally comprises an electric power unit supplied with current via an overhead contact line (catenary) which includes vertical supports holding a contact wire extending above the rails on which the railway vehicle travels. A pantograph is also installed on the roof of the electric power unit of the railway vehicle to collect the electric current flowing in the contact wire in order to supply the power unit with electrical energy during its movement on the rails, and in particular a battery. This pantograph typically comprises an articulated part supported by the roof of the power unit and a contact arm for receiving the current from the contact wire of the catenary. The traction battery thus stores electrical energy when the power unit passes over electrified sections of track in order to supply the electric motors of said power unit on non-electrified sections of track.

[0004] However, in order to ensure the energy autonomy of battery traction trains, the size of the energy storage means, and moreover, the amount of energy required for recharging, remains substantial.

[0005] This recharging can be done while driving on electrified sections of track or while stopped, particularly at the terminus station, before being able to leave again.

[0006] When the railway vehicle is stopped, the intensity of the current flowing from the catenary to the pantograph will create heating in the catenary at the level from the point of contact between the contact wire and the pantograph bow. This heating phenomenon is known, but nevertheless very limiting for the recharging of the energy storage units of the railway vehicle.

[0007] To overcome this heating phenomenon, the standards in force have evolved in order to define a limit value, regardless of the type of catenary: in particular 300A in direct current supply of 1500V or 80A in alternating current supply of 25kV in order to maintain a temperature less than or equal to 120°C at the point of contact.

[0008] However, the current solution seems insufficient in view of technological advances and the presence of large volume traction batteries for electric trains requires the ability to exceed these electrical power limits without damaging the catenary.

[0009] In addition, charging while stationary is generally slow and not optimized for high energy needs because of the aforementioned heating phenomenon.

[0010] The invention therefore proposes to address these different problems. Objectives of the invention

[0011] The invention aims to provide a system and a method for controlling the intensity of the recharging of a traction battery of a railway vehicle to limit heating in the catenary.

[0012] The invention also aims to provide, in at least one embodiment, a system and a control method enabling the optimization of the charging time of a traction battery of a railway vehicle.

[0013] The invention also aims to provide, in at least one embodiment, a control system and method that makes it possible to overcome current intensity limits in the event of a significant energy requirement.

[0014] The invention also aims to provide, in at least one embodiment, a system and a control method enabling the reduction of the downtime required for recharging the battery of a railway vehicle with traction battery.

[0015] The invention also aims to provide, in at least one embodiment, a system and a control method enabling the energy potential of catenary charging to be exploited without degrading it.

[0016] The invention also aims to provide, in at least one embodiment, a system and a control method enabling the optimization of charging as a function of the speed of the railway vehicle. Description of the invention

[0017] To this end, the invention relates to a method for controlling the charging intensity of a traction battery of a railway vehicle, said railway vehicle comprising a motor and a pantograph, configured to collect an electric current by contact of said pantograph with at least one contact wire of a catenary at the level of a contact zone, called the pantograph-catenary contact zone, so as to be able to electrically supply a traction battery of said railway vehicle with said electric current, said method being characterized in that it comprises: - a step El of acquiring a plurality of images of a pantograph mounted on said motor, of which at least one image is a thermographic image of said pantograph, - a step E2 of identifying a pantograph-catenary contact zone from at least one image of an acquired pantograph, - a step E3 of measuring the temperature of the pantograph-catenary contact zone identified from said thermographic image, to obtain a first temperature, called measured temperature Tm, corresponding to a temperature representative of at least one point of the identified pantograph-catenary contact zone, - a step E4 of controlling the charging intensity of a traction battery as a function of said measured temperature Tm.

[0018] Throughout this text, the term "charging current" refers to the intensity of the electric current required to recharge a traction battery of a railway vehicle. Charging can be a full recharge or a recharge that provides sufficient energy for the railway vehicle to reach the next electrified point.

[0019] It is also understood that the temperature of a point in the pantograph-catenary contact zone may correspond to the temperature of a specific point or to the average of all or part of the temperatures in said contact zone. In particular, the contact zone may be defined by a bounding box or by a coordinate system applicable to an image. In these cases, the calculation of the measured temperature Tm may correspond, for example, to a pixel point randomly chosen in said bounding box, a point representing the centroid of the bounding box, or to a value representative of the distribution of temperatures measured over a plurality of pixels in said bounding box, such as the mean or the median. Furthermore, the measured temperature Tm may be derived from any other suitable methods providing representative information on the temperature of the pantograph-catenary contact zone.

[0020] Thus and according to the invention, the method makes it possible to recharge the battery as quickly as possible in order to limit the immobilization of said railway vehicle.

[0021] Furthermore, the presence of on-board energy storage such as traction batteries results in an increase in the heating phenomenon caused by the intensity of the current going from the catenary to the pantograph at the level of said pantograph-catenary contact zone.

[0022] The method according to the invention thus makes it possible to ensure the rapid recharging of traction batteries within the regulatory limits imposed while avoiding damage to the catenary.

[0023] Such a process makes it possible to overcome the physical temperature limit of the point of contact between the pantograph and a catenary in the context of recharging a traction battery.

[0024] Advantageously and according to the invention, step E1 further includes the acquisition of at least one image in the visible light spectrum, called a non-thermographic image of said pantograph, step E2 of identification of a pantograph-catenary contact zone being carried out from at least one acquired non-thermographic image of the pantograph.

[0025] Advantageously and according to another variant of the invention, step E2 of identifying the pantograph-catenary contact area and step E3 of measuring the temperature of the pantograph-catenary contact area can be carried out from the same thermographic image.

[0026] Advantageously, and according to another embodiment of the invention, step E2 of identifying the pantograph-catenary contact area can be performed using a thermographic image and a non-thermographic image. Thus, according to the invention, such a step makes it possible to obtain a color image that is more easily recognizable by identification algorithms. Furthermore, it is thus easier to identify the pantograph's contact arm or horns from a non-thermographic image.

[0027] Advantageously and according to the invention, the method further comprises a step E201 of tracking said pantograph-catenary contact zone identified from a plurality of images acquired successively.

[0028] Thus and according to the invention, the method makes it possible to follow the pantograph-catenary contact zone as the railway vehicle progresses on the tracks of said vehicle.

[0029] Advantageously and according to the invention, the method further comprises a step E301 of comparing the measured temperature Tm with a second temperature, called the threshold temperature Ts, representative of a maximum permissible catenary temperature, and step E4 of controlling the charging current of a battery. traction controlling said intensity so that the measured temperature Tm is less than the threshold temperature Ts.

[0030] The maximum permissible catenary temperature is understood to be the normalized heating temperature of a catenary, or a temperature representative of the mechanical resistance of the catenary material in order to avoid the latter breaking.

[0031] Thus, according to the invention, the control method makes it possible to adapt the charging current of the traction battery based on a threshold temperature that depends on the infrastructure and the materials used for the catenaries. Furthermore, other parameters such as the temperature of the battery cells and the battery's charging rate can also contribute to adapting the charging current.

[0032] Advantageously and according to the invention, the method further comprises a step E302 of data acquisition relating to the geolocation of said railway vehicle, said geolocation data, said geolocation data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is also carried out according to said geolocation data.

[0033] Thus and according to the invention, the control method makes it possible to adapt the charging intensity according to the location of the railway vehicle, and in particular the presence of infrastructure and specific equipment on the traffic track used by said vehicle.

[0034] Advantageously and according to the invention, the method further comprises a step E303 of acquiring data relating to the state of charge of said traction battery of said railway vehicle, said state of charge data, said state of charge data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is further carried out according to said state of charge data.

[0035] Thus and according to the invention, the control system can take into account the state of charge of the traction battery before carrying out a control of the charging intensity, notwithstanding other intrinsic parameters of said battery.

[0036] Advantageously and according to the invention, the method further comprises a step E304 of acquiring data relating to the speed of said railway vehicle, said speed data, said speed data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is also carried out according to said speed data.

[0037] Thus, according to the invention, the control method makes it possible to adapt the battery charging intensity according to the speed of the railway vehicle and to discriminate between different phases of circulation of said vehicle between stopped phase, low speed circulation phase and cruising speed circulation phase.

[0038] The invention also relates to a system for controlling the charging intensity of a traction battery of a railway vehicle, said system being intended to be mounted on said railway vehicle, said railway vehicle comprising a power car, a pantograph mounted on said power car, said pantograph being configured to collect an electric current by friction with at least one contact wire of a catenary at the level of a contact zone, said pantograph-catenary contact zone, so as to be able to electrically supply a traction battery of said vehicle with said electric current, said system being characterized in that it comprises: • an image acquisition device comprising at least one image acquisition camera configured to be able to acquire a plurality of images of a pantograph mounted on said motor, of which at least one image is a thermographic image of said pantograph, • a module for identifying said pantograph-catenary contact zone configured to identify said pantograph-catenary contact zone from at least one acquired pantograph image, • a temperature measurement module, configured to measure the temperature of the pantograph-catenary contact area identified from said thermographic image and to obtain a first temperature, called measured temperature Tm, corresponding to a temperature representative of at least one point of the identified pantograph-catenary contact area, • a control module for the charging intensity of a traction battery of said railway vehicle configured to control the charging intensity of said traction battery as a function of said measured temperature Tm.

[0039] Advantageously and according to the invention, said image acquisition device comprises an image acquisition camera further configured to be able to acquire an image in the visible light spectrum, said non-thermographic image of said pantograph, said identification module being further configured to identify said pantograph-catenary contact area from said acquired non-thermographic image of the pantograph.

[0040] Advantageously and according to another variant of the invention, the pantograph-catenary contact zone identification module and the pantograph-catenary contact zone temperature measurement module can operate from the same thermographic image.

[0041] Advantageously and according to another variant of the invention, the pantograph-catenary contact zone identification module can operate from a thermographic image and a non-thermographic image.

[0042] Thus and according to the invention, the control system makes it easier to identify the characteristics of the pantograph and in particular the bow and the horns of said pantograph.

[0043] Advantageously, and according to the invention, the identification module comprises a first machine learning model trained to identify pantographs. This first learning model was trained using a first training image bank, referred to as the pantograph bank, comprising images of pantographs with a bow and horns. The pantographs are mounted on a railway vehicle. The first model is trained to categorize images representing pantograph horns and images representing the pantograph bow. According to this aspect, a model trained from images labeled using techniques known to a person skilled in the art is used for the identification step.

[0044] Advantageously and according to the invention, the control system further comprises a pantograph-catenary zone tracking module configured to track the position of said pantograph-catenary contact zone from a plurality of images acquired successively by at least one image acquisition camera of said image acquisition device.

[0045] The function of the tracking module can be activated on demand by the control system, for example it can be provided that this function is executed during the movement of the railway vehicle rather than when it is stopped.

[0046] Thus and according to the invention, the control system makes it possible to monitor the position of a pantograph-catenary contact zone despite the lateral misalignment and the variation in height of the catenary.

[0047] Advantageously and according to the invention, the control module for the charging intensity of said traction battery further comprises a temperature comparison sub-module configured to compare said measured temperature Tm with a second temperature, said threshold temperature Ts, representative of a maximum permissible catenary temperature, said control module being further configured to control said charging intensity so that the measured temperature Tm is lower than the threshold temperature Ts.

[0048] Thus and according to the invention, such a control system makes it possible to avoid damage caused by overheating of the catenary.

[0049] Advantageously and according to the invention, the system further comprises an acquisition unit configured to collect data, referred to as collected data, from among the following data: • data relating to the geolocation of said railway vehicle, referred to as geolocation data, • data relating to the state of charge of said traction battery of said railway vehicle, referred to as state of charge data, • data relating to the speed of said railway vehicle, referred to as speed data.

[0050] Thus, according to the invention, the control system makes it possible to determine the best charging strategy for controlling the charging intensity of a traction battery for each situation. Furthermore, it is understood that the system can choose to use all or part of this collected data.

[0051] Advantageously and according to the invention, the traction battery charging intensity control module is further configured to control the charging intensity of said battery based on at least one of said data collected.

[0052] Thus and according to the invention, the control system makes it possible to control and optimize the charging intensity of a traction battery of the railway vehicle in all circumstances.

[0053] Advantageously, the control system according to the invention is configured to implement the control method according to the invention.

[0054] Advantageously and according to the invention, the control method according to the invention is configured to be implemented by a control system according to the invention. List of figures

[0055] Other objects, features and advantages of the invention will become apparent from the following description, given by way of non-limiting example only, and which refers to the accompanying figures in which: • [Fig. 1] is a schematic view of a railway vehicle including an on-board control system, • [Fig.2] is a functional diagram of the control method according to one embodiment of the invention, • [Fig.3] is a functional diagram of the control system according to one embodiment of the invention, • [Fig.4] represents the heating results of the contact wire of a catenary at the current collection point with the pantograph when the railway vehicle is at rest.

[0056] Detailed description of an embodiment of the invention

[0057] In the figures, scales and proportions are not strictly observed, for the purposes of illustration and clarity. Furthermore, identical, similar, or analogous elements are designated by the same reference numerals in all figures.

[0058] With reference to [Fig. 1] and [Fig. 3], the described control system is a system embedded in a railway vehicle 10. Said system comprises a device acquisition 100 comprising at least one acquisition camera 50 mounted on the roof of a power car of said railway vehicle 10.

[0059] The railway vehicle 10 further includes a pantograph 20 configured to physically connect at least one contact wire 30 of a catenary arranged above a railway track on which said railway vehicle 10 can travel. The pantograph 20 is configured to collect an electric current by friction with at least one contact wire 30 of a catenary at the level of a contact area, referred to as the pantograph-catenary contact area 40, so as to be able to electrically supply, among other things, a traction battery of said railway vehicle 10. The pantograph-catenary contact area may, for example, correspond to the contact area between the pantograph bow 20 and at least one contact wire 30 of a catenary.

[0060] The control system includes, for example, a computer device 101, which should be understood in a broad sense (computer, plurality of computers, virtual server on the internet, virtual server in the cloud, virtual server on a platform, virtual server on a local infrastructure, server networks, etc.). This computer device 101 typically includes one or more computers 102, one or more memories 103 containing instructions for software routines used by the control system, and optionally a human-machine interface 104.

[0061] The control system may also include a database for saving the results of the control of the charging intensity of a traction battery of a railway vehicle and for accessing information relating to previous charging intensity control data, in particular on electrified or non-electrified track sections, or to control laws, or to laws of temperature evolution as a function of time and intensity.

[0062] The calculator 102 is an electronic circuit designed to manipulate and / or transform data represented by electronic or physical quantities in registers of the calculator 102 and / or memories into other similar data corresponding to physical data in register memories or other types of display devices, transmission devices or storage devices.

[0063] As specific examples, the computer 102 includes hardware such as a single-core or multi-core processor (such as a central processing unit (CPU), a graphics processing unit (GPU)) and modules. The computer 102 of the described embodiment is a railway computer designed and adapted to meet railway standards.

[0064] The control system is mounted on a railway vehicle 10 and includes an image acquisition device 100 comprising at least one image acquisition camera 50 configured to be able to acquire a plurality of images of a pantograph 20 mounted on a motor car of said railway vehicle 10, of which at least one image is a thermographic image of said pantograph 20.

[0065] In addition, the device 100 may include several image acquisition cameras 50, at least one of which is configured to acquire a thermographic image of the pantograph 20.

[0066] The image acquisition device 100 may also include one or more cameras configured to acquire two types of images, namely a first image, called a non-thermographic image, whose radiation belongs to the visible light spectrum with a trichromy of the Red Green Blue type, better known by the acronym RGB or by the English name RGB (Red Green Blue) or with a four-color process of the Cyan Magenta Yellow Black type, better known by the acronym CMYK or by the English name CMYK (Cyan Magenta Yellow Black), and a second image, whose radiation does not belong to the visible light spectrum, such as infrared or IR radiation, called a thermographic image. Furthermore, it is also conceivable that a single camera 50 could capture both types of image.

[0067] Throughout this text, the term "module" refers to a software element, a subset of a software program that can be compiled separately, either for independent use or for assembly with other program modules, or a hardware element, or a combination of a hardware element and a software subprogram. Such a hardware element may include an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or any equivalent hardware or combination thereof. Generally speaking, a module is therefore an element (software and / or hardware) that performs a function.

[0068] The control system further includes a module 200 for identifying the pantograph-catenary contact area 40, configured to identify said pantograph-catenary contact area 40 from at least one image of the pantograph 20 acquired by the image acquisition device 100. The identification of the pantograph-catenary contact area by the module 200 can be performed using a thermographic or non-thermographic image, or both.

[0069] In another embodiment, the identification of the pantograph-catenary contact zone 40 can be performed by the module 200 on a succession of images acquired by the image acquisition device 100. This can thus make it possible to obtain for each of the images an encompassing box of the pantograph-catenary contact zone 40.

[0070] Furthermore, it is also possible to provide that the identification module 200 may include a machine learning model trained to identify the pantograph-catenary contact area 40 on the images from the image acquisition device 100. As such, the module 200 may use a detection algorithm to detect on each image the position of the pantograph 20 and more particularly the position of the pantograph bow 20 and the contact wire 30 in order to deduce the pantograph-catenary contact area 40.

[0071] Such an algorithm may be an algorithm whose architecture is specific or pre-designed, for example an algorithm known to a person skilled in the art such as YOLO.

[0072] The control system further includes a temperature measurement module 300, configured to measure the temperature of the pantograph-catenary contact area 40 identified from said thermographic image and to obtain a first temperature, referred to as the measured temperature Tm, corresponding to the temperature of at least one point of the identified pantograph-catenary contact area 40. To this end, when the pantograph-catenary contact area 40 has been identified by the identification module 200, the module 200 allows, for example, the assignment of a bounding box at the level of the pantograph-catenary contact area 40, the point corresponding to a pixel of the image of said pantograph-catenary contact area.

[0073] The temperature measurement module 300 allows the bounding box coordinates assigned to the pantograph-catenary contact area 40 to be used to target a precise area in the obtained thermographic image and extract the associated temperature. Furthermore, the temperature measurement can be performed using a thermal imager such as an IR camera or any other equivalent means for retrieving a temperature, referred to as the measured temperature Tm, from a thermographic image.

[0074] The described control system includes a pantograph-catenary contact zone 40 tracking module configured to track the position of said pantograph-catenary contact zone 40 from a plurality of images acquired successively by at least one image acquisition camera 50 of said image acquisition device 100. For this purpose, the module 300 can use a tracking algorithm enabling it to track, on each image, the position of the pantograph-catenary contact zone 40 identified by the module 200 on each of the successively acquired images.

[0075] Such a tracking algorithm may be an algorithm whose architecture is specific or pre-designed, for example an algorithm known to those skilled in the art such as SORT or DeepSORT.

[0076] In the described embodiment, the control system includes a control module 500, configured to control the charging intensity of a traction battery of said railway vehicle 10 as a function of said measured temperature Tm.

[0077] The control module 500 further includes a temperature comparison sub-module 510 configured to compare said measured temperature Tm with a second temperature, said threshold temperature Ts, representative of a maximum permissible catenary temperature, said control module 500 being configured to control said charging intensity so that the measured temperature Tm is lower than the threshold temperature Ts.

[0078] The comparison sub-module 510 allows, for example, the control module 500 to control the battery charging current according to the following control laws: • If Tm < 0.6 x Ts then the charging intensity will be maximum • If Tm > 0.6 x Ts, then the charging current will be reduced so that T < Tm — -1 s* • If Tm > Ts, then the charging of the traction battery is stopped and the charging current will be zero

[0079] These control laws are given purely for illustrative purposes and the invention is not limited to them. Furthermore, the method and system according to the invention make it possible to exploit the acceptable heating temperature range of the catenary to accelerate the recharging of a traction battery of the railway vehicle as a function of the temperature of said catenary, notwithstanding other parameters (temperature of the battery cells, initial state of charge, target state of charge, etc.).

[0080] The control system may also include an acquisition unit 600 configured to collect data 610 relating to the geolocation of said railway vehicle, referred to as geolocation data, data 620 relating to the state of charge of said traction battery of said railway vehicle, referred to as state of charge data, as well as data 630 relating to the speed of said railway vehicle 10, referred to as speed data.

[0081] All of this data, referred to as collected data, can be processed, notwithstanding other parameters, by the control module 500 in order to determine the charging intensity of the traction battery of the railway vehicle 10 as a function of the measured temperature Tm, the threshold temperature Ts and said geolocation data 610, charge state data 620 and speed data 630.

[0082] It is understood that the control system 500 can use all or any of said data 610, 620 and 630.

[0083] The geolocation data 610 can thus be used by the control module 500 to determine whether the rail vehicle 10 is on an electrified track or not. This can allow the control module 500 to adapt the charging intensity according to the length of the electrified track, for example.

[0084] The battery charge status data 620 can be used by the control module to adapt the charging current of the traction battery of the railway vehicle 10 according to its charge status at the start of charging. Indeed, the control system can take this information into account to command a rapid charge of the traction battery based on the amount of energy required to recharge it.

[0085] In addition, the control module 500 can be powered by data on temperature evolution as a function of time and intensity.

[0086] The speed data 630 can be used by the control module 500 to discriminate between the "stop" phases, corresponding to zero speed of the railway vehicle, the "low speed" phases corresponding to a slow speed of the railway vehicle 10 where the latter is moving at idle speed, and the "movement" phases corresponding to the movement of the railway vehicle 10 at its cruising speed.

[0087] Since the heating of the pantograph-catenary contact area 40 is not equivalent depending on the different phases mentioned above, these speed data 630 can be advantageously used by the charging intensity control system.

[0088] The most efficient recharging takes place when stopped, and heating of the pantograph-catenary contact area 40 linked to the passage of current to allow rapid recharging of a traction battery of the railway vehicle is all the more important when said vehicle 10 is stopped.

[0089] The control system and the method for controlling the charging intensity according to the invention thus make it possible in all circumstances to take full advantage of the potential of charging by catenary while avoiding degradation related to heat.

[0090] According to the embodiment of the invention described, the machine learning model, and in particular a machine learning model adapted to image processing and / or a deep learning model, for example a neural network.

[0091] It is understood that the detection system described is capable of implementing the steps of the process according to [Fig.2].

[0092] Fig. 2 schematically represents a method for controlling the charging intensity of a traction battery of a railway vehicle according to an embodiment of the invention.

[0093] The process starts with a step El of acquiring a plurality of images of a pantograph 20 mounted on the roof of a motor car of a railway vehicle 10.

[0094] Image acquisition is carried out by means of an image acquisition device 100 comprising one or more image acquisition cameras 50 configured to obtain thermographic (IR) and / or non-thermographic (RGB or CMYK) images of the pantograph 20. The acquisition camera 50 is capable of obtaining successive image sequences of the pantograph 20 and may include a wide-angle lens.

[0095] The method includes a step E2 of identifying a pantograph-catenary contact zone from at least one image of an acquired pantograph 20, said step E2 being consecutive to step EL

[0096] Step E2 is performed by an identification algorithm for module 200, which identifies the pantograph-catenary contact area 40. The identification algorithm can be trained to identify and label features of interest in the acquired images, such as the specific shape of the pantograph bow 20 or the bow's horns. Thus, a convolutional neural network can advantageously be used to detect the visual characteristics of the pantograph-catenary contact area 40 and enable bounding box labeling of the areas of interest.

[0097] The method may include a step 201 for tracking the position of the pantograph-catenary contact zone identified in step E2. This step may be carried out using images acquired successively by the acquisition device 100 in order to track the movement of the pantograph-catenary contact zone 40 during the movement of the railway vehicle 10. This makes it possible, for example, to ensure tracking of the zone 40 while taking into account the variation in height of the contact wire 30 and the lateral movement of the zone 40 of interest as a function of the path followed by the railway vehicle 10.

[0098] The process continues with a step E3 following step E2 of measuring the temperature of the pantograph-catenary contact zone 40 identified from a thermographic (IR) image, to obtain a first temperature, called measured temperature Tm, corresponding to the temperature of a point of the identified pantograph-catenary contact zone 40.

[0099] This step is carried out by a temperature measurement module 300, configured to measure the temperature of the pantograph-catenary contact area 40 identified from said thermographic image and obtain a first temperature, said measured temperature Tm, corresponding to the temperature of a point in the pantograph-catenary contact zone 40 identified.

[0100] Module 300 allows extraction of temperature data from the identified pantograph-catenary contact area, notably through the use of a thermal imager.

[0101] The process continues with a step E4 of controlling the charging current of a traction battery as a function of the measured temperature Tm. This step E4 is carried out by a control module 500 comprising a sub-module 510 for comparing the measured temperature Tm with a threshold temperature Ts. The temperature comparison can be performed during a temperature comparison step E301 by the sub-module 510.

[0102] In addition, the control module 500 is configured to process the geolocation data 610, the traction battery charge status data 620 and the speed of the railway vehicle 10, each of said data being acquired during the respective acquisition steps E301, E302 and E304 carried out by an acquisition unit 600 of the control system.

[0103] The control module 500 is thus configured to process all the data mentioned above to control the charging intensity of a traction battery of the railway vehicle 10 as a function of the measured temperature Tm and said data.

[0104] Fig. 4 shows the results of the temperature evolution of a catenary wire as a consequence of the capture of electric current by a pantograph 20 of a railway vehicle 10 equipped with a control system for the charging intensity of a traction battery according to an embodiment of the invention.

[0105] The graph includes four tests representative of the evolution of the temperature of the pantograph-catenary contact area 40 as a function of the intensity called by the railway vehicle 10 when the latter is at rest.

[0106] The threshold temperature predetermined by the sizing of the infrastructure used for the tests is 120°C. This temperature has been reduced to a heating value of 85K (Kelvin) by taking into account the external conditions.

[0107] The measured temperature Tm measurements are also translated into Kelvin heating value and appear on the ordinate axis under the name "measured heating".

[0108] It is then observed that for the four intensities tested (300A, 500A, 800A and 1000A), heating of the catenary pantograph contact area never exceeds the threshold temperature of 85 K.

[0109] The control system therefore makes it possible to control the charging intensity of a traction battery by making the best use of the intensity called for by the infrastructure and in particular when the railway vehicle is stopped.

Claims

Demands

1. A method for controlling the charging intensity of a traction battery of a railway vehicle, said railway vehicle comprising a power car and a pantograph, configured to capture an electric current by contact of said pantograph with at least one contact wire of a catenary at the level of a contact zone, said pantograph-catenary contact zone, so as to be able to electrically supply a traction battery of said railway vehicle with said electric current, said method being characterized in that it comprises: • a step E1 of acquiring a plurality of images of a pantograph mounted on said power car, at least one image of which is a thermographic image of said pantograph, • a step E2 of identifying a pantograph-catenary contact zone from at least one image of a pantograph acquired,• a step E3 of measuring the temperature of the pantograph-catenary contact zone identified from said thermographic image, to obtain a first temperature, said measured temperature Tm, corresponding to a temperature representative of at least one point of the identified pantograph-catenary contact zone, • a step E4 of controlling the charging intensity of a traction battery as a function of said measured temperature Tm.

2. A method according to claim 1, characterized in that step E1 further comprises the acquisition of at least one image in the visible light spectrum, referred to as a non-thermographic image of said pantograph, and in that step E2 of identifying a pantograph-catenary contact zone is carried out from at least one acquired non-thermographic image of the pantograph.

3. A method according to any one of the preceding claims, characterized in that it further comprises a step E201 of tracking said pantograph-catenary contact zone identified from a plurality of images acquired successively.

4. A method according to any one of the preceding claims, characterized in that it further comprises a step E301 of comparing the measured temperature Tm with a second temperature, called threshold temperature Ts, representative of a maximum permissible catenary temperature, the step E4 of controlling the charging intensity of a traction battery controlling said intensity so that the measured temperature Tm is lower than the threshold temperature Ts.

5. A method according to any one of the preceding claims, characterized in that it further comprises a step E302 of acquiring data relating to the geolocation of said railway vehicle, said geolocation data, said geolocation data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is further carried out according to said geolocation data.

6. A method according to any one of the preceding claims characterized in that it further comprises a step E303 of acquiring data relating to the state of charge of said traction battery of said railway vehicle, said state of charge data, said state of charge data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is further carried out according to said state of charge data.

7. A method according to any one of the preceding claims characterized in that it further comprises a step E304 of acquiring data relating to the speed of said railway vehicle, said speed data, said speed data being used in step E4 of controlling the charging intensity of a traction battery so that the control of the charging intensity is further carried out according to said speed data.

8. A system for controlling the charging intensity of a traction battery of a railway vehicle (10), said system being intended to be mounted on said railway vehicle (10), said railway vehicle (10) comprising a power car, a pantograph (20) mounted on said power car, said pantograph (20) being configured to collect an electric current by friction with at least one wire of contact (30) of a catenary at the level of a contact zone, called the pantograph-catenary contact zone (40), so as to be able to electrically supply a traction battery of said vehicle with said electric current, said system being characterized in that it comprises: • an image acquisition device (100) comprising at least one image acquisition camera (50) configured to be able to acquire a plurality of images of a pantograph (20) mounted on said motor, of which at least one image is a thermographic image of said pantograph (20), • a module (200) for identifying said pantograph-catenary contact zone (40) configured to identify said pantograph-catenary contact zone (40) from at least one image of the pantograph (20) acquired, • a temperature measurement module (300), configured to measure the temperature of the pantograph-catenary contact area (40) identified from said thermographic image and obtain a first temperature, called measured temperature Tm, corresponding to a temperature representative of at least one point of the identified pantograph-catenary contact area (40), • a module (500) for controlling the charging intensity of a traction battery of said railway vehicle configured to control the charging intensity of said traction battery as a function of said measured temperature Tm.

9. System according to claim 8, characterized in that said image acquisition device (100) comprises an image acquisition camera (50) further configured to be able to acquire an image in the visible light spectrum, said non-thermographic image of said pantograph, and in that said identification module (200) is further configured to identify said pantograph-catenary contact area (40) from said acquired non-thermographic image of the pantograph.

10. A system according to any one of claims 8 to 9, characterized in that it further comprises a pantograph-zone tracking module (400) catenary (40) configured to track the position of said pantograph-catenary contact zone (40) from a plurality of images acquired successively by at least one image acquisition camera (50) of said image acquisition device (100).

11. System according to any one of claims 8 to 10, characterized in that the control module (500) of the charging intensity of said traction battery further comprises a temperature comparison sub-module (510) configured to compare said measured temperature Tm with a second temperature, said threshold temperature Ts, representative of a maximum permissible catenary temperature, said control module (500) further being configured to control said charging intensity so that the measured temperature Tm is lower than the threshold temperature Ts.

12. A system according to any one of claims 8 to 11, characterized in that it further comprises an acquisition unit (600) configured to collect data, referred to as collected data, from among the following: - data (610) relating to the geolocation of said railway vehicle, referred to as geolocation data, - data (620) relating to the state of charge of said traction battery of said railway vehicle, referred to as state of charge data, - data (630) relating to the speed of said railway vehicle, referred to as speed data,

13. System according to claim 12, characterized in that the traction battery charging intensity control module (500) is further configured to control the charging intensity of said battery as a function of at least one of said data collected (610, 620, 630).

14. A system according to any one of claims 8 to 13, characterized in that the identification module comprises a first machine learning model trained to identify pantographs, this first learning model having been trained using a first training image bank, referred to as the pantograph bank, comprising images representing pantographs including a bow and horns, said pantographs being mounted on a railway vehicle, the said first model being trained to categorize the images representing the pantograph horns and the images representing the pantograph bow.

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