Method for controlling a pantograph comprising an electric actuator, pantograph and rail vehicle implementing such a method
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- FAIVELEY TRANSPORT TOURS
- Filing Date
- 2024-06-26
- Publication Date
- 2026-05-06
AI Technical Summary
Existing pantograph systems for electric railway vehicles face challenges in regulating force exerted on catenaries, leading to unsatisfactory current capture and complex design and operation, particularly due to the use of pneumatic actuators which make it difficult to control the force effectively.
A method for controlling a pantograph using an electric actuator that measures force exerted on a catenary, determines instantaneous position and compensation forces, and adjusts the actuator to maintain optimal force, accounting for weight, aerodynamic loads, and environmental conditions, thereby enabling direct and safe regulation of the panto-catenary force.
This method allows for precise control of the panto-catenary force, avoiding over- or under-efforts, and ensures reliable contact with the catenary, even at varying speeds and conditions, improving power supply efficiency and simplifying the design and operation of pantograph systems.
Smart Images
Figure FR2024050844_02012025_PF_FP_ABST
Abstract
Description
Description Title: Method for controlling a pantograph comprising an electric actuator, pantograph and railway vehicle implementing such a method TECHNICAL FIELD OF THE INVENTION [1] The field of the invention is that of electric vehicles powered by catenaries, such as electric railway vehicles (trains) or urban passenger transport vehicles (tram, metro, etc.). [2] More specifically, the invention relates to a method for controlling a pantograph comprising an electric actuator, and a pantograph and a railway vehicle implementing such a method. [3] The invention finds applications in particular in the field of electrical power supply for trains equipped with articulated pantographs. STATE OF THE ART [4] The use of articulated pantographs to supply electricity to a vehicle is known from the prior art, via a catenary in contact with the pantograph. [5] Known articulated pantograph systems generally comprise an articulated system, or frame, allowing the raising and lowering of a bow mounted at one end of the articulated system, and intended to come into contact with a catenary. [6] In order to move the articulated system, the latter is generally equipped with an actuator which can be controlled to raise or lower the bow during the operation of the vehicle which is equipped with the pantograph. [7] The actuators used in prior art pantographs are primarily pneumatic actuators, of the type comprising a pneumatic cushion cooperating with the articulated system to cause deployment of the pantograph when the cushion is under pressure. [8] For example, known "CX Pantograph" type pantograph systems include a cam and sling system for applying torque to the lower arm of the articulated system when the cushion is under pressure. [9] In general, the descent of the pantograph is carried out by the purging of the cushion, the articulated system folding under the effect of gravity, possibly supported by the action of a return spring.
[0010] Other known systems involve lifting springs, adapted to deploy the pantograph by the force of a loaded lifting spring.
[0011] In such systems, electric actuators may be provided to drive the pantograph down, working against the action of the up spring.
[0012] The known systems have in common that the regulation of the force exerted by the bow relative to a catenary is particularly complex, even impossible in certain cases.
[0013] This results in unsatisfactory current capture, with significant complexity in terms of design and operation of such systems.
[0014] There is therefore a need for a pantograph which allows the regulation of a force relative to a catenary in a more direct, simple and safe way. STATEMENT OF THE INVENTION
[0015] The present invention aims to remedy all or part of the drawbacks of the state of the art cited above.
[0016] To this end, the invention relates to a method for controlling a pantograph of a railway vehicle, the pantograph being of the type comprising a head comprising a bow, at least one force sensor for measuring a force representative of the force exerted by the bow relative to a catenary, an articulated system for raising and lowering the bow, and an electric actuator capable of exerting a force on the articulated system to raise and lower the bow, the control method comprising the steps of:
[0017] - measure a force representative of the force exerted by the bow relative to the catenary; and
[0018] - determine an instantaneous position of rise / fall of the pantograph; and
[0019] - determine a so-called pantograph weight compensation force value, from the instantaneous raising / lowering position of the pantograph and a first set of data, associating data representative of the force exerted on the actuator by the weight of the pantograph and the pantograph up / down position data; and
[0020] - controlling the electric actuator by a loop controlling the force exerted by the bow relative to the catenary, in response to an instantaneous force setpoint, said instantaneous force setpoint being determined from the so-called compensation force value of the weight of the pantograph and a so-called compensation force value at the head of the pantograph, established prior to the step of controlling the electric actuator.
[0021] Thanks to these arrangements, unlike the known technique, it is possible to take advantage of the knowledge of the position of the pantograph (i.e. the extent to which it is extended / retracted) to control the pantograph force.
[0022] This is made possible by the fact that the pantograph has an electric actuator for raising / lowering the pantograph. It should be noted here that the pantograph does not have a pneumatic actuator, unlike the known technique.
[0023] It should be noted that it is this electric actuator which allows the pantograph to be raised and lowered for its activation or deactivation, and for the regulation of the pantograph-catenary force when it is in operation.
[0024] Controlling the pantograph force as a function of the position of the pantograph is particularly advantageous because it allows for taking into account, in particular, differences in level of the catenary relative to the pantograph, as well as the rotation of these differences in level.
[0025] It is thus possible to avoid over- and under-efforts of the panto-catenary effort.
[0026] The method allows, unlike known techniques and in particular known techniques based on pneumatic actuators, to extend the regulation possibilities by taking into account the operating conditions of the pantograph.
[0027] It should be noted that the so-called compensation force value at the head of the pantograph can be fixed or variable and can be established, i.e. defined or calculated, before determining the instantaneous force setpoint.
[0028] The so-called compensation force value at the head of the pantograph corresponds to a value of a force to be compensated which is exerted at the level of the head of pantograph during the operation of the railway vehicle, which may be due to various factors, in particular external to the pantograph.
[0029] Other particularly advantageous embodiments of the method are described below.
[0030] Preferably, the method further comprises the steps of:
[0031] - determine an instantaneous forward speed of the railway vehicle; and
[0032] - determine a value known as the compensation force at the head of the pantograph, from the instantaneous forward speed of the railway vehicle and a second set of data, combining data representative of the force to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph and forward speed data of the railway vehicle.
[0033] Thanks to these provisions, it is also possible to take into account the forward speed of the railway vehicle, and therefore the aerodynamic load exerted on the pantograph, to control the pantograph force.
[0034] This is particularly advantageous for railway vehicles normally running at high speed (above 200 km / h) and where the aerodynamic load is particularly high, and where it is therefore particularly important that the panto-catenary force can be regulated so as to guarantee satisfactory contact between the bow and the catenary.
[0035] However, these provisions may also apply to railway vehicles usually running at lower speeds, particularly trams.
[0036] Preferably, in the method, the second data set is established from predefined aerodynamic load data according to the forward speed of the railway vehicle.
[0037] Thus, for a given pantograph, in the second dataset, a predefined aerodynamic load value is associated with a vehicle forward speed.
[0038] For example, the aerodynamic load values are predefined in that they come from simulation data or from calculating the aerodynamic load as a function of forward speed.
[0039] In other words, aerodynamic load data is not data determined, measured or calculated in real time during execution of the process, and do not necessarily correspond to a real-time aerodynamic load exerted on the pantograph.
[0040] Preferably, in the method, the second data set is also established from at least one piece of data external to the pantograph, relating to the implementation environment of the pantograph.
[0041] Thanks to these provisions, it is possible to take into account even more fully the operating conditions of the pantograph (other than the forward speed of the vehicle).
[0042] Preferably, in the method, the data external to the pantograph comprises at least one of: the position of the pantograph on the railway vehicle, the type of catenary with which the bow is in contact, a set speed for raising and / or lowering the pantograph, the forward speed of the railway vehicle, the direction of forward movement of the railway vehicle, the wind speed in the environment of the pantograph, the movement and / or the speed of movement of the articulated system, the instantaneous position of raising / lowering of the pantograph, the intensity of the current flowing between the catenary and the pantograph, the presence of the railway vehicle in a tunnel, the coupling of the railway vehicle in multiple units.
[0043] Preferably, alternatively, in the method, the so-called compensation force value at the head of the pantograph is a predefined constant force value.
[0044] Such an arrangement constitutes an alternative to determining an aerodynamic load value exerted on the pantograph, with a constant force value aimed at ensuring sufficient contact of the bow with the catenary.
[0045] This is particularly advantageous for railway vehicles usually running at low speed (less than 200 km / h) and where the aerodynamic load is less significant, and where a predetermined constant force is sufficient for satisfactory panto-catenary contact.
[0046] However, these provisions may also apply to railway vehicles normally running at high speed, and where the greater aerodynamic load may, for example, be compensated by structural means of the pantograph such as ailerons.
[0047] Preferably, in the method, the first and / or the second data set is established prior to an execution of the method.
[0048] Preferably, in the method, the first data set also associates data on the direction of rise / fall of the pantograph with the data representative of the force exerted on the actuator by the weight of the pantograph and with the data on the position of rise / fall of the pantograph, and in which the so-called compensation force value at the head of the pantograph is also determined from an instantaneous direction of rise / fall of the pantograph.
[0049] It is thus possible to take into account the evolution of the operating conditions of the pantograph, and in particular when the difference in level of the catenary relative to the pantograph varies considerably during the movement of the vehicle.
[0050] Preferably, in the method, the instantaneous force setpoint is determined by the addition of the so-called compensation force value of the weight of the pantograph and the so-called compensation force value at the head of the pantograph.
[0051] Preferably, in the method, the instantaneous raising / lowering position of the pantograph is determined from a position value provided by a position encoder of the actuator, and from a predetermined relationship between the position of the actuator and the position of the pantograph.
[0052] Preferably, the method further comprises the step of comparing the value of the measured force with a predetermined maximum force value, and the method comprises a step of emergency lowering of the pantograph which is executed by the method when the value of the measured force is greater than the predetermined maximum force value.
[0053] Preferably, in the method, the pantograph is of the type comprising a first and a second force sensor for measuring a force representative of the force exerted by the bow relative to a catenary, the step of measuring the force representative of the force exerted by the bow relative to the catenary comprising a measurement by the first sensor and a countermeasurement by the second sensor.
[0054] This makes it possible to provide additional security in the event of a measurement anomaly from one of the sensors, and to avoid any over- or under-stressing of the panto-catenary force.
[0055] The invention also relates, in a second aspect, to a pantograph comprising a bow, at least one force sensor for measuring a force representative of the force exerted by the bow relative to a catenary, an articulated system for raising and lowering the bow, a control module of the pantograph, and an electric actuator capable of exerting a force on the articulated system to raise and lower the bow, the pantograph control module being configured to implement the control method as described above.
[0056] Other particularly advantageous embodiments of the pantograph are described below.
[0057] Preferably, the pantograph further comprises a lifting spring capable of exerting an elastic force on the articulated system so as to allow or support the lifting of the bow, the lifting spring and the electric actuator being arranged according to a force association in parallel.
[0058] Preferably, in the pantograph, the step of controlling the electric actuator, implemented by the control module, is a step of controlling a force directly exerted by the electric actuator on the articulated system.
[0059] Preferably, alternatively the pantograph further comprises a lifting spring capable of exerting an elastic force on the articulated system so as to allow or support the lifting of the bow, the lifting spring and the electric actuator being arranged according to a series force association.
[0060] Preferably, in the pantograph, the step of controlling the electric actuator, implemented by the control module, is a step of controlling a position of one end of the lifting spring.
[0061] Preferably, alternatively the pantograph comprises two lifting springs and the electric actuator which are arranged in a double force association both in parallel and in series.
[0062] The invention also relates, in a third aspect, to a railway vehicle comprising a pantograph as described above. BRIEF DESCRIPTION OF THE FIGURES
[0063] Other advantages, aims and particular characteristics of the present invention will emerge from the following non-limiting description of at least one particular embodiment of the devices and methods which are the subject of the present invention, with reference to the appended drawings, in which: - Figure 1 schematically represents a first type of pantograph, with an architecture of the lifting spring and the electric actuator in parallel, in a deployed position of the pantograph; - figure 2 schematically represents the pantograph of figure 1, in a folded position of the pantograph; - Figure 3 schematically represents a second type of pantograph, with an architecture of the lifting spring and the electric actuator in series, in a deployed position of the pantograph; - figure 4 schematically represents the pantograph of figure 3, in a folded position of the pantograph; - Figure 5 schematically represents a third type of pantograph, with an architecture of the lifting spring and the electric actuator in double association both in parallel and in series, in a deployed position of the pantograph; - figure 6 schematically represents the pantograph of figure 5, in a folded position of the pantograph; - Figure 7 is a flowchart of a pantograph control method implemented by a pantograph; - Figure 8 is a functional diagram of an example of a panto-catenary force control loop operating in the method of Figure 7. DETAILED DESCRIPTION OF THE INVENTION
[0064] This description is given without limitation, each characteristic of an embodiment being able to be combined with any other characteristic of any other embodiment in an advantageous manner.
[0065] Please note, from now on, that the figures are not necessarily to scale.
[0066] Figures 1 to 6 schematically represent a pantograph 100, here mounted on the roof 10 of a railway vehicle.
[0067] In the illustrated example, the pantograph 100 comprises a frame 116 which is mounted on the roof 10, for example by means of electrical insulators 20.
[0068] The pantograph 100 is an articulated device which can be in the folded position, in the erected or deployed position. It is in this deployed position, as shown in FIG. 1 in particular, that the pantograph can capture the electric current ensuring the power supply of a motor of the railway vehicle, via a catenary 30 supplied with electricity.
[0069] The pantograph 100 shown is of the “single-arm” type and comprises an articulated frame or system 110 comprising a lower arm 111 and an upper arm 112, connected in an articulated manner.
[0070] On the one hand, the lower arm 111 is mechanically connected by one of its ends to the frame 116 of the pantograph, via a first articulation 113.
[0071] On the other hand, the lower arm 111 is connected by its other end to one of the ends of the upper arm 112, via a second articulation 114.
[0072] The upper arm 112 supports the pantograph head 120 at its other end, via an articulation.
[0073] The pantograph head 120 comprises a bow 121 which rubs on the catenary 30 when the pantograph 100 is in the deployed position. A friction strip (not shown) generally made of carbon is mounted on the upper face of the bow 121, and is adapted to rub on the catenary 30 to capture the electric current which passes there.
[0074] The articulated system 110 thus forms a system for raising / lowering the bow 121.
[0075] Figure 1 shows a deployed position of the pantograph 100, the bow 121 being mounted, in a high position in contact with the catenary 30.
[0076] Figure 2 shows a folded position of the pantograph 100, the bow 121 being lowered, in a low position without contact with the catenary 30.
[0077] The pantograph 100 comprises an actuator for moving from the folded position to the deployed position, and vice versa. The actuator is thus able to exert a force on the articulated system 110 to raise and lower the bow 121.
[0078] In particular, the actuator is an electric actuator 130. In the example illustrated, the electric actuator 130 is an electric linear actuator. An electric actuator is understood to mean an actuator whose main energy source is electrical energy, and which therefore does not depend on a fluid supply network as is the case for a pneumatic or hydraulic actuator. The pantograph 100 is thus devoid of any fluid actuator to exert a force on the articulated system 110 to raise and lower the bow 121.
[0079] However, it is not excluded that the electric actuator 130 can be controlled at least in part by means of a fluid signal.
[0080] The articulated system 110 comprises a lever arm 115 secured to the lower arm 111, and the electric actuator 130 acts on the articulated system 110 by acting on the lever arm 115.
[0081] By exerting a force on the lever arm 115, the electric actuator 130 exerts a moment of force on the lower arm 111, which is thus caused to pivot around the first articulation 113.
[0082] It is specified that the pantograph illustrated schematically in figures 1 to 6 may include other known components, which are not illustrated.
[0083] For example, a single-arm pantograph generally comprises a coupling bar substantially parallel to the lower arm 111, and a guide substantially parallel to the upper arm 112, making it possible to ensure the horizontality of the bow 121 when the latter is raised or lowered. These elements are however neither described nor shown in detail, the design of a single-arm pantograph being known in the art.
[0084] It is also specified that if necessary, the bow 121 can be suspended on the pantograph head via suspensions.
[0085] In addition, the pantograph 100 may also include a double-bow head 120.
[0086] The pantograph 100 shown in Figures 1 to 6 also optionally comprises one or more lifting springs 140. The lifting springs are, for example, helical traction springs.
[0087] In the example illustrated in Figures 1 and 2, the pantograph 100 comprises a lifting spring 140 (dotted) arranged in a force association in parallel with the electric actuator 130.
[0088] By parallel force association is meant that the electric actuator 130 and the lifting spring 140 both act directly on the articulated system 110. The physical arrangement of the electric actuator 130 and the lifting spring 140 is however not necessarily parallel in the geometric sense.
[0089] In the example illustrated in Figures 3 and 4, the pantograph 100 comprises a lifting spring 140 arranged in a series force association with the electric actuator 130.
[0090] By series force association is meant that one of the electric actuator 130 and the lifting spring 140 acts on the other of the electric actuator 130 and the lifting spring 140, which acts directly on the articulated system 110. In the example illustrated, the electric actuator 130 acts on the lifting spring 140, which itself acts on the articulated system 110.
[0091] In the example illustrated in Figures 5 and 6, the pantograph 100 comprises two lifting springs 140 (one of which is shown in dotted lines) arranged in a double force association both in parallel and in series with the electric actuator 130.
[0092] By double force association both in parallel and in series is meant the fact that the system comprises a subassembly with a first lifting spring 140 spring and the electric actuator 130 arranged in series as defined above, and this subassembly and the second lifting spring 140 both act directly on the articulated system 110.
[0093] The presence of a lifting spring 140 is advantageous for supporting the action of the electric actuator 130 during the raising of the pantograph.
[0094] The pantograph 100 may however be without a lifting spring 140 in certain embodiments.
[0095] In addition, the pantograph 100 may in certain embodiments be equipped with an electric actuator 130 other than an electric linear cylinder, for example an electric rotary motor, for example with direct drive.
[0096] The pantograph 100 further comprises at least one force sensor 150. The force sensor 150 is configured to measure a force representative of the force exerted by the bow 121 relative to the catenary 30, that is to say a force representative of the force known as “panto-catenary force”.
[0097] The force sensor 150 can be arranged at the level of the bow 121 in order to directly measure the force exerted by the bow 121 relative to the catenary 30.
[0098] The force sensor 150 can also be arranged at the level of the frame 116, and be configured to indirectly measure the force exerted by the bow 121 relative to the catenary 30, as shown in FIGS. 1 to 6.
[0099] For this, a force at the articulated system 110 can be measured by the force sensor 150, then converted into a panto-catenary force value according to a predetermined relationship.
[0100] The force sensor 150 is connected by a wired or non-wired data link (dotted in the figures) to a control module 160 of the pantograph.
[0101] The control module 160 may be a dedicated module for each pantograph 100 of a railway vehicle on which the pantograph 100 is mounted. It may also be a control module common to several pantographs 100, or a central control unit of the railway vehicle.
[0102] The control module 160 is connected by a data or electrical signal link (not shown) to the electric actuator 130, so as to be able to control its actuation.
[0103] The control module 160 notably comprises a non-volatile data storage memory, and a control unit comprising for example one or more microcontrollers and / or microprocessors (not shown).
[0104] In one embodiment, the pantograph 100 may comprise a second force sensor (not shown), for example arranged in a similar manner to the first force sensor 150, in order to allow a countermeasurement of the force representative of the pantograph-catenary force.
[0105] The operation of the pantograph 100 will now be described in more detail.
[0106] Referring to Figure 2, when the pantograph 100 is in the folded position, the lower arm 111 and upper arm 112 are brought together and the pantograph 100 is in a configuration in which the height of the pantograph 100, from the frame 116 to the bow 121, is minimal or at least minimized.
[0107] Referring to Figure 1, when the pantograph 100 is in the deployed position, the lower arm 111 and upper arm 112 are spaced apart from each other and the pantograph 100 is in a configuration in which the height of the pantograph 100, from the frame 116 to the bow 121, is greater. The height of the deployed pantograph 100 depends on the distance from the roof 10 of the railway vehicle to the catenary 30 and may vary depending on the conditions of implementation of the pantograph.
[0108] The raising spring 140, arranged in a force association in parallel with the electric actuator 130, is in a tensioned state when the pantograph is in the stowed position. Therefore, it tends to drive the pantograph 100 into the extended position, in which the raising spring 140 is in a less tensioned state.
[0109] In the embodiment illustrated in Figures 3 and 4, the operation of the pantograph 100 is similar.
[0110] Here, the electric actuator 130 acts on one of the ends of the lifting spring 140 so as to move it by a determined distance. The elastic force which results from the variation in length of the lifting spring 140 is applied by the lifting spring 140 to the lever arm 115. Here also, the operation is such that the lifting spring 140 is in a state of tension when the pantograph 100 is folded.
[0111] Similarly, in the embodiment illustrated in Figures 5 and 6, the operation of the pantograph 100 corresponds to the combined operation of the embodiments of Figures 1 and 2, and 3 and 4.
[0112] The lifting spring(s) 140, whatever the embodiment, may be sized so as to substantially compensate for the weight of the pantograph 100, however substantially without allowing the application of a contact force on the catenary 30.
[0113] The contact force is applied by the electric actuator 130, which can be precisely controlled. This allows for a smaller dimensioning of the electric actuator 130, the main role of which is the control of the pantograph force, but not necessarily the deployment of the pantograph.
[0114] The lifting spring(s) 140 may in particular be sized so as to exert a force slightly less than the force necessary to compensate for the weight of the pantograph 100, so that, when the pantograph 100 passes from the deployed position to the folded position, the pantograph 100 passes into the folded position under the sole effect of gravity.
[0115] However, it is possible that the electric actuator 130 can also act on the articulated system 110 in order to accelerate the transition to the folded position of the pantograph 100, in particular in the event of an emergency, for example due to an anomaly at the level of the bow 121.
[0116] In the illustrated examples, in the stowed position, the piston of the electric linear cylinder forming the electric actuator 130 is extended. In the deployed position, the piston of the electric linear cylinder forming the electric actuator 130 is further retracted.
[0117] It is thus understood that the electric actuator 130 “pulls” (directly or indirectly via a lifting spring 140) on the lever arm 115 to raise the pantograph (i.e. to move from the position shown in figure 2 to that of figure 1).
[0118] As discussed above, the lifting springs 140 are helical tension springs in the illustrated examples, which also "pull" on the lever arm 115.
[0119] It is however possible for the operation to be reversed, that is to say that the electric actuator 130, and where appropriate the lifting spring(s) 140, “pushes” on the lever arm 115 to raise the pantograph. In such a case, the arrangement of the pantograph 100 is adapted accordingly to allow such operation. In particular, the lifting springs 140 may then be helical compression springs.
[0120] The pantograph 100 is configured to implement a method 200 for controlling the pantograph, illustrated by the flowchart of FIG. 7.
[0121] More specifically, the control module 160 may be configured to implement the method 200, for example by storing in the non-volatile data storage memory instructions leading the control unit to implement the steps of the method 200.
[0122] The method 200 may comprise a preliminary step 201 of verifying that an order to raise, or deploy, the pantograph 100 has been given.
[0123] The climb order can be given, for example, when starting the railway vehicle, automatically or manually, from a control unit remote from the pantograph 100.
[0124] When a raise order is detected, the pantograph 100 is deployed until the bow 121 comes into contact with the catenary 30.
[0125] The method 200 comprises a measurement step 210, in which a force representative of the force exerted by the bow 121 relative to the catenary 30 is measured by means of at least the force sensor 150.
[0126] The force exerted by the bow relative to the catenary may vary depending in particular on the unevenness of the catenary relative to the track on which the railway vehicle is traveling, and / or depending on the force exerted by the electric actuator 130 on the catenary, via the bow 121.
[0127] Step 210 may comprise a countermeasurement of the force representative of the force exerted by the bow 121 relative to the catenary 30, by means of at least one second force sensor.
[0128] When the measurements of the force sensors differ, or their difference exceeds a predefined tolerance margin, the method 200 may comprise sending of alert information to an operator and / or the execution of an emergency lowering step of the pantograph 100.
[0129] The method 200 also comprises a step 220 of determining an instantaneous raising / lowering position of the pantograph.
[0130] Step 220 can be performed for example by reading a position value of the electric actuator 130 from a position encoder of the electric actuator 130, which then comprises such a position encoder (not shown).
[0131] In order to determine the instantaneous raising / lowering position of the pantograph (which may for example correspond to a height of the bow 121 relative to the roof 10 of the railway vehicle, or of the frame 116 of the pantograph 100), a predetermined relationship between the position of the electric actuator 130 and the position of the pantograph 100 is previously established. The instantaneous raising / lowering position of the pantograph is for example determined by a calculation of conversion of the position of the electric actuator 130 into the instantaneous raising / lowering position of the pantograph, via said predetermined relationship.
[0132] The method 200 further comprises a step 230 of determining a so-called pantograph weight compensation force value.
[0133] The pantograph weight compensation force value is determined from the instantaneous raising / lowering position of the pantograph previously determined, and from a first set of data, associating data representative of the force exerted on the actuator by the weight of the pantograph and data on the raising / lowering position of the pantograph.
[0134] In particular, the first data set is determined or established prior to an execution of the method 200.
[0135] The first data set may be stored in the form of a computer table in the non-volatile storage memory of the control module 160. The data entered in the computer table associates a value representative of the force exerted on the electric actuator 130 by the weight of the pantograph with each of the positions of a plurality of predefined pantograph raising / lowering positions.
[0136] In particular, the values representative of the force exerted on the electric actuator 130 by the weight of the pantograph may be values representative of the force exerted on the electric actuator 130 by the weight of the pantograph in the absence of any other external stress.
[0137] The pantograph weight compensation force value is determined or established for example by interpolation, or where appropriate extrapolation, of data representative of the force exerted on the actuator by the weight of the pantograph, for the instantaneous raising / lowering position of the pantograph previously determined.
[0138] It is specified that the weight compensation effort of the pantograph varies as a function of the instantaneous raising / lowering position of the pantograph, in particular due to the geometry of the articulated system 110, but also the dynamics of the pantograph varying the weight “felt” by the electric actuator 130 during the movement of the pantograph 100.
[0139] The “dynamic” weight of the pantograph 100 can vary depending on the direction of actuation of the pantograph.
[0140] Thus, the first data set can also associate data on the direction of rise / fall of the pantograph with data representative of the force exerted on the actuator by the weight of the pantograph and with data on the position of rise / fall of the pantograph.
[0141] During step 230, the pantograph weight compensation force value is then also determined from an instantaneous direction of rise / fall of the pantograph.
[0142] The instantaneous direction of rise / fall of the pantograph can for example be determined by reading an actuation direction value of the electric actuator 130 (for example a binary value) from the position encoder of the electric actuator 130.
[0143] In such a case, the computer table may include two pantograph weight compensation force values per pantograph up / down position, one in the up direction and the other in the down direction.
[0144] Optionally, the method 200 also comprises a step 240 of determining an instantaneous forward speed of the railway vehicle.
[0145] For example, this information may be received from a central control unit, or on-board computer, of the railway vehicle.
[0146] Optionally, when the method 200 comprises the step 240 of determining an instantaneous forward speed of the railway vehicle, the method 200 further comprises a step 250 of determining a value called compensation force at the head of the pantograph which is here a value of compensation force for an aerodynamic load exerted on the pantograph.
[0147] The value of the force for compensating for an aerodynamic load exerted on the pantograph is determined or established from the instantaneous forward speed of the railway vehicle previously determined and from a second set of data, combining data representative of the force to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph and forward speed data of the railway vehicle.
[0148] In particular, the second data set is established or determined prior to an execution of the method 200.
[0149] The second data set may also be stored in the form of a computer table in the non-volatile storage memory of the control module 160. The data entered in the computer table associates a value representative of the force to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph at each of a plurality of forward speeds of the railway vehicle.
[0150] The value of the force for compensating for an aerodynamic load exerted on the pantograph is determined or established, for example, by interpolation, or where appropriate extrapolation, of the data representative of the force to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph, for the instantaneous forward speed of the railway vehicle previously determined.
[0151] It is specified that the compensation force value for an aerodynamic load corresponds to a predefined setpoint value according to the forward speed of the railway vehicle, but not necessarily to a compensation force value for an actual aerodynamic load instantly experienced by the pantograph.
[0152] In particular, the force values to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph may be normative values specifying a minimum force to be exerted relative to the catenary for a given forward speed, in order to avoid any loss of contact with the catenary.
[0153] Furthermore, the second data set can also be determined or established from at least one data item external to the pantograph, relating to the implementation environment of the pantograph.
[0154] More precisely, the force values to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph can depend on the external data, and the force value for compensating for an aerodynamic load is then determined as a function of the forward speed of the railway vehicle and the external data.
[0155] Thus, the context of implementation of the pantograph on a railway vehicle, and / or the type of railway vehicle on which the pantograph is installed, and / or the environment of the track on which the railway vehicle operates can be taken into account. These parameters linked to the environment of the pantograph can in fact have an influence on the minimum force to be exerted relative to the catenary.
[0156] For example, the data external to the pantograph comprises at least one of the following data, and in any possible combination: the position of the pantograph on the railway vehicle, the type of catenary with which the bow is in contact, a speed instruction for raising and / or lowering the pantograph, the forward speed of the railway vehicle, the forward direction of the railway vehicle, the wind speed of the environment of the pantograph, the movement and / or the speed of movement of the articulated system, the instantaneous raising / lowering position of the pantograph, the intensity of the current flowing between the catenary and the pantograph, the presence of the railway vehicle in a tunnel, the coupling of the railway vehicle in multiple units, or not, that is to say the information according to which the railway vehicle comprises a single set of cars or wagons, or several sets of coupled cars or wagons.
[0157] The method 200 also comprises a step 260 of controlling the electric actuator 130.
[0158] During this step, or prior to this step, an instantaneous force setpoint, corresponding to a force setpoint to be exerted by the bow 121 relative to the catenary 30 at a given instant, is determined.
[0159] The instantaneous force setpoint is determined from the pantograph weight compensation force value and the previously established compensation force value at the pantograph head.
[0160] The compensation force value at the head of the pantograph can be established during step 250, and then corresponds to the compensation force value of an aerodynamic load exerted on the pantograph described above.
[0161] Alternatively, in particular when the method 200 does not include the step 240 of determining a forward speed of the railway vehicle, the compensation force value at the head of the pantograph, previously established, may be a constant and predefined force value, for example 100 N. This value is then independent in particular of the forward speed of the railway vehicle.
[0162] For example, the instantaneous force setpoint is determined by adding the pantograph weight compensation force value and the previously established pantograph head compensation force value. Other methods of determining the instantaneous force setpoint, for example by weighted addition, are also conceivable.
[0163] The instantaneous force setpoint is thus a function of the raising / lowering position of the pantograph, and when the method includes steps 240 and 250, of the forward speed of the railway vehicle, as real-time data during the operation of the railway vehicle.
[0164] Step 260 of controlling the electric actuator 130 comprises controlling the electric actuator 130 by a loop for controlling the force exerted by the bow 121 relative to the catenary 30, in response to the instantaneous force setpoint.
[0165] It is specified here that when the pantograph 100 is of the parallel force association type, the control of the electric actuator 130 can be a control of a force directly exerted by the electric actuator 130 on the articulated system 110.
[0166] When the pantograph 100 is of the series force association type, the control of the electric actuator 130 may be a step of controlling a position of one end of the lifting spring 140.
[0167] When the pantograph 100 is of the double force association type in parallel and in series, the control of the electric actuator 130 may be a step of controlling a position of one end of the lifting spring 140 mounted in series with the other lifting spring 140 and the electric actuator 130.
[0168] For example, the control loop is a control loop comprising a "PID" type controller. Such control loops are known in the art and are not described in detail here.
[0169] Figure 8 illustrates in the form of a block diagram an example of a control loop comprising a PID regulator, and also schematically illustrates the determination of the panto-catenary force setpoint at the input of the control loop.
[0170] The parameters of such a control loop can be freely chosen according to the methods for determining parameters known in the art. The control loop should be configured so as to minimize the error between the instantaneous force setpoint and the value of the force exerted by the bow relative to the catenary, measured by the force sensor. It is also appropriate to obtain a control loop with a short reaction time, without however inducing excessive oscillations of the bow 121.
[0171] It is specified that the steps of the method 200 are not necessarily all executed sequentially. In particular, steps 230 and 250 can be executed in parallel, as illustrated in Figure 7.
[0172] More generally, the method 200 can be executed in a loop with a predetermined periodicity, so that the force exerted by the bow 121 relative to the catenary 30 is adapted at regular frequency to the operating conditions of the railway vehicle.
[0173] The method 200 may also comprise a monitoring step (not shown in the flowchart of FIG. 7), in which the force exerted by the bow relative to the catenary is compared to a maximum force value. If the maximum force value is exceeded, the emergency descent of the pantograph may be commanded. The emergency descent may for example be carried out by an accelerated descent using the electric actuator 130, or by any other suitable means capable in particular of overcoming a failure of the electric actuator 130.
[0174] It is recalled more generally that the invention is not limited to the examples described and illustrated.
Claims
Claims 1. Method (200) for controlling a pantograph (100) of a railway vehicle, the pantograph being of the type comprising a head comprising a bow (121), at least one force sensor (150) for measuring a force representative of the force exerted by the bow relative to a catenary (30), an articulated system (110) for raising and lowering the bow, and an electric actuator (130) capable of exerting a force on the articulated system to raise and lower the bow, the control method comprising the steps of: - (210) measure a force representative of the force exerted by the bow relative to the catenary; and - (220) determining an instantaneous position of rise / fall of the pantograph; and - (230) determining a so-called pantograph weight compensation force value, from the instantaneous raising / lowering position of the pantograph and a first set of data, associating data representative of the force exerted on the actuator by the weight of the pantograph and data on the raising / lowering position of the pantograph; and - (260) controlling the electric actuator by a loop controlling the force exerted by the bow relative to the catenary, in response to an instantaneous force setpoint, said instantaneous force setpoint being determined from the so-called compensation force value of the weight of the pantograph and a so-called compensation force value at the head of the pantograph, established prior to step (260) of controlling the electric actuator.
2. The method (200) of claim 1, further comprising the steps of: - (240) determine an instantaneous forward speed of the railway vehicle; and - (250) determining a value known as the compensation force at the head of the pantograph, from the instantaneous forward speed of the railway vehicle and a second set of data, combining data representative of the force to be exerted by the actuator to compensate for an aerodynamic load exerted on the pantograph and forward speed data of the railway vehicle.
3. Method (200) according to claim 2, in which the second data set is established from predefined aerodynamic load data according to the forward speed of the railway vehicle.
4. Method (200) according to claim 3, in which the second data set is also established from at least one data item external to the pantograph, relating to the implementation environment of the pantograph.
5. Method (200) according to claim 4, in which the data external to the pantograph comprises at least one of: - the position of the pantograph on the railway vehicle, - the type of catenary with which the bow is in contact, - a speed instruction for raising and / or lowering the pantograph, - the forward speed of the railway vehicle, - the direction of travel of the railway vehicle, - the wind speed in the pantograph environment, - the movement and / or speed of movement of the articulated system, - the instantaneous position of the pantograph raising / lowering, - the intensity of the current flowing between the catenary and the pantograph, - the presence of the railway vehicle in a tunnel, - coupling the railway vehicle into multiple units.
6. Method (200) according to claim 1, in which the so-called compensation force value at the head of the pantograph is a predefined constant force value.
7. Method (200) according to any one of claims 2 to 5, in which the first and / or the second data set is established prior to an execution of the method.
8. Method (200) according to any one of the preceding claims, in which the first data set also associates data on the direction of rise / fall of the pantograph with the data representative of the force exerted on the actuator by the weight of the pantograph and with the data on the position of rise / fall of the pantograph, and in which the so-called compensation force value at the head of the pantograph is also determined from an instantaneous direction of rise / fall of the pantograph.
9. Method (200) according to any one of the preceding claims, in which the instantaneous force setpoint is determined by the addition of the value called the pantograph weight compensation force and the so-called compensation force value at the head of the pantograph.
10. Method (200) according to any one of the preceding claims, in which the instantaneous raising / lowering position of the pantograph is determined from a position value provided by a position encoder of the actuator, and from a predetermined relationship between the position of the actuator and the position of the pantograph.
11. A method (200) according to any preceding claim, further comprising the step of comparing the measured force value with a predetermined maximum force value, and the method (200) comprising a step of emergency lowering of the pantograph which is performed by the method when the measured force value is greater than the predetermined maximum force value.
12. Method (200) according to any one of the preceding claims, the pantograph being of the type comprising a first and a second force sensor for measuring a force representative of the force exerted by the bow relative to a catenary, the step of measuring the force representative of the force exerted by the bow relative to the catenary comprising a measurement by the first sensor and a countermeasurement by the second sensor.
13. Pantograph (100) comprising a bow (121), at least one force sensor (150) for measuring a force representative of the force exerted by the bow relative to a catenary (30), an articulated system (110) for raising and lowering the bow, a control module (160) of the pantograph, and an electric actuator (130) capable of exerting a force on the articulated system to raise and lower the bow, the control module (160) of the pantograph being configured to implement the control method according to any one of claims 1 to 12.
14. Pantograph (100) according to claim 13, further comprising a lifting spring (140) capable of exerting an elastic force on the articulated system (110) so as to allow or support the lifting of the bow (121), the lifting spring (140) and the electric actuator (130) being arranged according to a force association in parallel.
15. Pantograph (100) according to claim 14, wherein the step (260) of controlling the electric actuator, implemented by the control module, is a step of controlling a force directly exerted by the electric actuator (130) on the articulated system (110).
16. Pantograph (100) according to claim 13, further comprising a lifting spring (140) capable of exerting an elastic force on the articulated system (110) so as to allow or support the lifting of the bow (121), the lifting spring (140) and the electric actuator (130) being arranged according to a series force association.
17. Pantograph (100) according to claim 16, wherein the step (260) of controlling the electric actuator (130), implemented by the control module, is a step of controlling a position of one end of the raising spring (140).
18. A pantograph (100) according to claim 14, and any one of claims 16 and 17, taken in combination, comprising two lifting springs (140) and the electric actuator (130) which are arranged in a dual force association both in parallel and in series.
19. Railway vehicle comprising a pantograph (100) according to any one of claims 13 to 18.