Calibration method and system for pantograph-catenary contact pressure sensor

Abstract

The invention discloses a calibration method and system for a pantograph-catenary contact pressure sensor, and the method comprises the steps: sequentially applying a force with a specified strength at each intersection point of a sliding plate and a support of a pantograph to be measured, respectively measuring the voltage of each intersection point when the force is applied each time, and obtaining a sensitivity coefficient matrix of all intersection point pressure sensors based on the voltages; during application, the actual contact pressure of the pressure sensor is obtained by utilizing the sensitivity coefficient matrix according to the real-time voltage of the to-be-measured pantograph at each intersection point.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor calibration, and in particular to a calibration method and system for a pantograph-catenary contact pressure sensor. Background Art

[0002] The pantograph-catenary contact pressure is an important parameter to measure the current-collecting performance of the pantograph-catenary. Whether it is high-speed railway or urban rail transit, the existing standard policies (such as TB 10761-2013, Jiaobanyun

[2019] No. 17, etc.) clearly stipulate that the contact pressure between the pantograph and the catenary is a necessary item for the detection of the pantograph-catenary relationship. Therefore, the accuracy of the pantograph-catenary contact pressure detection is crucial. The current contact pressure detection method (based on EN50317-2012) generally arranges the contact pressure sensor at the connection between the slide base and the bracket. For the double slide pantograph, a four-pressure sensor arrangement is generally adopted, as shown below Figure 1 shown.

[0003] (1) For the single-row slide, the center load method is to place a fixed kilogram weight at the center of the pantograph single-row slide, and assume that the force on each sensor under the slide is half of the weight of the weight, and then calculate its sensitivity based on the ratio of the sensor output value to the force. However, in actual field problems, since the tooling, sensitivity, and initial values ​​of each pressure sensor are not consistent, the sensitivity values ​​of each sensor obtained by roughly assuming that the force on each sensor is consistent are not accurate, and the mutual influence of the positions of each sensor during the actual operation of the train (the contact line is arranged in a zigzag shape) is ignored, resulting in large errors in the actual detection results.

[0004] (2) In addition, the existing contact pressure calibration method is to use a jack to support the contact network from below, and compare the pressure value detected by the pressure sensor (tensile gauge) in the pantograph system with the actual pressure value obtained by the pantograph system to complete the calibration. However, this method has a comparison error, that is, the actual force of the pantograph system is not necessarily the force detected (tensile gauge force), and this method requires large equipment, such as insulating rods, horizontal bases, etc., and has the problems of complex operation and large measurement errors.

[0005] (3) Another contact pressure calibration method is to use the design of screw motors, pressure sensors, laser displacement sensors, etc., to change the deformation of the contact network, obtain the corresponding relationship between the contact pressure and the deformation, and compare the contact pressure with the contact pressure obtained by the pantograph detection system. However, this calibration method is still relatively cumbersome, and the corresponding relationship between the deformation and the pressure sensor is subject to the influence of many factors, especially in the complex operating environment of the railway, there are large errors, and currently most urban rail transit uses rigid contact networks, which will not cause contact network deformation. This method is not suitable for pressure detection of rigid contact networks.

[0006] In summary, the above methods (2) and (3) are limited by the actual situation and equipment, the calibration process is relatively complicated, and the conditions are relatively harsh. Method (1) is subject to the different initial performance of the pressure sensor. With the increase in the service life of the train, in order to accurately obtain the contact pressure between the pantograph and the catenary, in addition to sensing the sensitivity data of the pressure sensor on the force-bearing side, the sensitivity on the opposite side must also be considered to reflect the mutual influence of the forces on each sensor under actual operating conditions. Summary of the invention

[0007] The object of the present invention is to provide a sensitivity coefficient calibration scheme that can take into account the mutual influence between different sensors in the same pantograph.

[0008] In order to solve the above technical problems, an embodiment of the present invention provides a calibration method for a pantograph-net contact pressure sensor, comprising: applying a force of specified intensity in sequence at each intersection of the slide plate and the bracket of the pantograph to be tested, measuring the voltage of each intersection when the force is applied each time, and based on this, obtaining a sensitivity coefficient matrix for all intersection pressure sensors; when applied, according to the real-time voltage of the pantograph to be tested at each intersection, using the sensitivity coefficient matrix, the actual contact pressure of the pressure sensor is obtained.

[0009] Preferably, the process of generating the sensitivity coefficient matrix includes: constructing a force matrix about the pantograph to be tested according to the intensity and application position of the specified force applied at each intersection; constructing a sensor output voltage matrix about the pantograph to be tested according to the voltage at each intersection when the force is applied each time; and obtaining the sensitivity coefficient matrix according to the force matrix and the sensor output voltage matrix.

[0010] Preferably, in the process of constructing the force matrix, the rows of the matrix represent the number of times the specified force is applied to the corresponding intersection position individually, and the columns of the matrix represent the amplitude of the force applied to each intersection, wherein the force amplitude of the intersection that is not affected by the specified force is zero by default.

[0011] Preferably, in the process of constructing the sensor output voltage matrix, the rows of the matrix represent the number of times the specified force is applied to the corresponding intersection positions, and the columns of the matrix represent the voltage change at each intersection.

[0012] Preferably, the step of obtaining the sensitivity coefficient matrix based on the force matrix and the sensor output voltage matrix includes: first calculating the inverse matrix of the force matrix, and then obtaining the sensitivity coefficient matrix by calculating the product matrix of the inverse matrix of the force matrix and the sensor output voltage matrix.

[0013] Preferably, when there are two intersection points between the slide plate and the bracket of the pantograph to be tested, the force matrix is:

[0014]

[0015] Among them, F M represents the force matrix, F represents the amplitude of the specified force, and the sensor output voltage matrix is:

[0016]

[0017] Among them, U M represents the sensor output voltage matrix, U 11 , U 12 They represent the voltage changes of the two intersections when the specified force is applied to the first intersection alone, U 21 , U 22 They respectively represent the voltage changes of the two intersections when the specified force is applied to the second intersection alone.

[0018] Preferably, the sensitivity coefficient matrix is ​​calculated using the following expression:

[0019]

[0020] Among them, K M represents the sensitivity coefficient matrix, F M represents the force matrix, U M Represents the sensor output voltage matrix.

[0021] Preferably, in the step of obtaining the actual contact pressure of the pressure sensor according to the real-time voltage of the pantograph to be tested at each intersection by using the sensitivity coefficient matrix, it includes: obtaining the voltage change at the corresponding intersection according to the real-time voltage at each intersection, and constructing a sensor dynamic output voltage matrix; according to the sensor dynamic output voltage matrix, using the inverse matrix of the sensitivity coefficient matrix, calculating the dynamic contact pressure matrix that characterizes the real-time contact pressure at each intersection.

[0022] Preferably, the direction of the force applied to each intersection individually is vertically downward, wherein the process of applying the specified force is simulated by sequentially hanging weights having the same strength as the specified force at each intersection.

[0023] On the other hand, an embodiment of the present invention further provides a calibration system for a pantograph-net contact pressure sensor, the calibration system being used to implement the calibration method as described above, wherein the calibration system comprises: a pressure sensor, wherein a corresponding pressure sensor is provided at each intersection of the slide plate and the bracket of the pantograph to be tested, and each pressure sensor is used to measure the voltage at each intersection when a specified force is applied to different intersections separately each time; a specified force applying unit, which is used to apply a specified force to each pressure sensor respectively; and a data management and analysis module, which is used to obtain a sensitivity coefficient matrix of all intersection pressure sensors according to the applied specified force and the voltage of each intersection when the force is applied each time, and in the actual application process of the pantograph to be tested, the actual contact pressure of the pressure sensor is obtained according to the real-time voltage of the pantograph to be tested at each intersection by using the sensitivity coefficient matrix.

[0024] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0025] The present invention proposes a calibration method and system for bow-net contact pressure sensors. The method and system simultaneously observe the output of each sensor under load conditions, determine each sensitivity through tests at different load-bearing points, take into account the mutual influence between the sensors, and comprehensively consider the contribution of each sensor to the force, and use a new calibration method to calculate the sensitivity coefficient of each sensor itself and each other, so as to obtain a more accurate calibration calculation result. In addition, the sensitivity coefficient obtained by performing calibration experiments on each load-bearing point in advance is input into the bow-net relationship detection, so that the bow-net contact pressure of the entire line can be calculated in real time, and the bow-net relationship can be evaluated. In this way, the present invention considers the mutual influence of the forces on each sensor when the force is applied at different points, calculates the contribution of each sensor to the force in turn, and calibrates the sensitivity coefficient of each sensor. It considers more factors and the calculation results are more accurate.

[0026] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 This is a schematic diagram of the arrangement of four pressure sensors of an existing double-slide pantograph.

[0029] Figure 2The diagram is a schematic diagram of the existing pressure calibration method for the arrangement of four pressure sensors of the existing double-slide pantograph.

[0030] Figure 3 Schematic diagram of the steps of a calibration method for a pantograph-catenary contact pressure sensor according to an embodiment of the present application.

[0031] Figure 4 Schematic diagram of the pressure calibration principle in the calibration method for the pantograph-catenary contact pressure sensor according to an embodiment of the present application.

[0032] Figure 5 It is a structural schematic diagram of a calibration system for a pantograph-catenary contact pressure sensor according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0034] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that here.

[0035] The terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "one", "one" and "item" used herein are also intended to include plural numbers. It should also be understood that the terms "include" and / or "comprise" used herein specify the existence of stated features, integers, steps, operations, units and / or components, without excluding the existence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0036] The pantograph-catenary contact pressure is an important parameter to measure the current-collecting performance of the pantograph-catenary. Whether it is high-speed railway or urban rail transit, the existing standard policies (such as TB 10761-2013, Jiaobanyun

[2019] No. 17, etc.) clearly stipulate that the contact pressure between the pantograph and the catenary is a necessary item for the detection of the pantograph-catenary relationship. Therefore, the accuracy of the pantograph-catenary contact pressure detection is crucial. The current contact pressure detection method (based on EN50317-2012) generally arranges the contact pressure sensor at the connection between the slide base and the bracket. For the double slide pantograph, a four-pressure sensor arrangement is generally adopted, as shown below Figure 1 shown.

[0037] (1) For the single-row slide, the center load method is to place a fixed kilogram weight at the center of the pantograph single-row slide, and assume that the force on each sensor under the slide is half of the weight of the weight, and then calculate its sensitivity based on the ratio of the sensor output value to the force. However, in actual field problems, since the tooling, sensitivity, and initial values ​​of each pressure sensor are not consistent, the sensitivity values ​​of each sensor obtained by roughly assuming that the force on each sensor is consistent are not accurate, and the mutual influence of the positions of each sensor during the actual operation of the train (the contact line is arranged in a zigzag shape) is ignored, resulting in large errors in the actual detection results.

[0038] (2) In addition, the existing contact pressure calibration method is to use a jack to support the contact network from below, and compare the pressure value detected by the pressure sensor (tensile gauge) in the pantograph system with the actual pressure value obtained by the pantograph system to complete the calibration. However, this method has a comparison error, that is, the actual force of the pantograph system is not necessarily the force detected (tensile gauge force), and this method requires large equipment, such as insulating rods, horizontal bases, etc., and has the problems of complex operation and large measurement errors.

[0039] (3) Another contact pressure calibration method is to use the design of screw motors, pressure sensors, laser displacement sensors, etc., to change the deformation of the contact network, obtain the corresponding relationship between the contact pressure and the deformation, and compare the contact pressure with the contact pressure obtained by the pantograph detection system. However, this calibration method is still relatively cumbersome, and the corresponding relationship between the deformation and the pressure sensor is subject to the influence of many factors, especially in the complex operating environment of the railway, there are large errors, and currently most urban rail transit uses rigid contact networks, which will not cause contact network deformation. This method is not suitable for pressure detection of rigid contact networks.

[0040] In summary, the above methods (2) and (3) are limited by the actual situation and equipment, the calibration process is relatively complicated, and the conditions are relatively harsh. Method (1) is subject to the different initial performance of the pressure sensor. With the increase in the service life of the train, in order to accurately obtain the contact pressure between the pantograph and the catenary, in addition to sensing the sensitivity data of the pressure sensor on the force-bearing side, the sensitivity on the opposite side must also be considered to reflect the mutual influence of the forces on each sensor under actual operating conditions.

[0041] In order to solve the technical problems in the above-mentioned background technology, the embodiment of the present application proposes a calibration method and system for bow-net contact pressure sensors. Starting from the perspective of the sensor, the method and system consider the mutual influence of the forces on each sensor when the force is applied at different intersections, calculate the contribution of each sensor to the force in turn, and calibrate the sensitivity coefficient of each sensor. Compared with the calibration method in the prior art, the number of sensitivity coefficients required to be counted in the present invention is twice that of the traditional one, and it considers more factors and the calculation results are more accurate.

[0042] Figure 2 The diagram is a schematic diagram of the existing pressure calibration method for the arrangement of four pressure sensors in the existing double-slide pantograph. The existing calibration method is to install the four sensors at the (four) connections between the slide base and the bracket in the double-slide pantograph, record the static voltage of each connection under no-load condition and mark the static voltage as zero. Assume Figure 2 The weight of the middle weight is 5kg, so the force on each sensor is 24.5N, and the difference between the output voltage of each sensor and the zero point is ΔU1, ΔU2, ΔU3 and ΔU4. Furthermore, the sensitivity coefficients of each sensor are K1, K2, K3 and K4, and their expressions are:

[0043]

[0044] Among them, K i represents the sensitivity coefficient of the i-th sensor.

[0045] Figure 3 The following is a schematic diagram of the steps of the calibration method for the pantograph-catenary contact pressure sensor according to the embodiment of the present application. The specific steps of the calibration method according to the embodiment of the present invention are described below.

[0046] In step S310, a force of specified intensity is applied in sequence at each intersection point (i.e., the above-mentioned connection point) of the slide plate and the bracket of the pantograph to be tested, and the voltage of each intersection point when the force is applied is measured respectively, so as to obtain the sensitivity coefficient matrix of the pressure sensors at all the intersection points according to the specified force applied each time and the voltage of each intersection point when the force is applied each time.

[0047] In step S310, a specified force of the same magnitude is applied to each intersection point in turn. The direction of the specified force is vertically downward. Each time a force is applied, the sensor output voltage at each intersection point needs to be measured by a pressure sensor disposed at each intersection point to obtain a voltage change amount at each intersection point compared to the zero-point voltage. In an embodiment of the present invention, the pressure sensor is a piezoelectric sensor.

[0048] In one embodiment, the process of applying the specified force is simulated by sequentially hanging weights having the same strength as the specified force at each intersection.

[0049] Figure 4 Schematic diagram of the pressure calibration principle in the calibration method for the pantograph-catenary contact pressure sensor according to an embodiment of the present application. Figure 4 The pressure calibration principle is demonstrated when there are two intersections between the slide and the bracket of the pantograph to be tested. When the weight is first applied to sensor 1 (a specified force is applied to the first intersection alone), the voltage change (compared to the zero voltage) corresponding to the output voltage of the pressure sensor 1 at the first intersection is U 11 The voltage change (compared to the zero voltage) corresponding to the output voltage of the pressure sensor 2 at the second intersection is U 12 When the weight is applied to sensor 2 (a specified force is applied to the second intersection alone), the voltage change (compared to the zero voltage) corresponding to the output voltage of pressure sensor 1 at the first intersection is U 21 The voltage change (compared to the zero voltage) corresponding to the output voltage of the pressure sensor 2 at the second intersection is U 22 .

[0050] To this end, step S310 also obtains the sensitivity coefficient matrix of the pressure sensors at all intersections according to the position and strength of the specified force applied each time, and the voltage change of each intersection when the force is applied each time. The sensitivity coefficient matrix contains information about the mutual influence of the forces on each sensor when the specified force is applied at different intersections. Specifically, the sensitivity coefficient matrix has characteristic information including the contribution of the sensor at each intersection to the specified force.

[0051] In the process of generating the sensitivity coefficient matrix, first, a force matrix about the pantograph to be tested is constructed according to the strength and application position of the specified force applied at each intersection. Specifically, the rows of the force matrix represent the number of times the specified force is applied to the corresponding intersection position individually, and the columns of the force matrix represent the amplitude of the force applied to each intersection. Among them, the force amplitude of the intersection that is not subjected to the specified force is zero by default.

[0052] In one embodiment, when there are two intersection points between the slide plate and the bracket of the pantograph to be tested, the force matrix is:

[0053]

[0054] Among them, F M represents the force matrix, and F represents the amplitude of the specified force.

[0055] Then, according to the voltage change corresponding to the voltage at each intersection when the force is applied each time, the sensor output voltage matrix of the pantograph to be tested is constructed. Specifically, the rows of the sensor output voltage matrix represent the number of times the specified force is applied to the corresponding intersection position, and the columns of the sensor output voltage matrix represent the voltage change at each intersection. Each element in the sensor output voltage matrix represents the voltage change of the voltage value output by the current position sensor under the action of the specified force applied this time.

[0056] In one embodiment, when there are two intersections between the slide plate and the bracket of the pantograph to be tested, the sensor output voltage matrix is:

[0057]

[0058] Among them, U M represents the sensor output voltage matrix, U 11 , U 12 They represent the voltage changes of the two intersections when a specified force is applied to the first intersection alone, U 21 , U 22 They respectively represent the voltage changes of the two intersections when a specified force is applied to the second intersection alone.

[0059] After the force matrix and the sensor output voltage matrix are constructed, step S310 will also obtain a sensitivity coefficient matrix based on the constructed force matrix and the sensor output voltage matrix. Each element in the sensitivity coefficient matrix represents the influence (contribution) of the voltage output by the current position sensor on the specified force applied at the current time.

[0060] Specifically, the inverse matrix of the force matrix is ​​calculated first, and then the sensitivity coefficient matrix is ​​obtained by calculating the product matrix of the inverse matrix of the force matrix and the sensor output voltage matrix.

[0061] In one embodiment, when there are two intersections between the slide plate and the bracket of the pantograph to be tested, the sensitivity coefficient matrix is ​​calculated using the following expression:

[0062]

[0063] Among them, K M represents the sensitivity coefficient matrix, F M represents the force matrix, U M represents the sensor output voltage matrix, K 11 , K 12 They represent the sensor sensitivity coefficients of the two intersection points when a specified force is applied to the first intersection point alone, K 21 , K 22They represent the sensor sensitivity coefficients of the two intersection points when a specified force is applied to the second intersection point alone. In other words, K 11 K represents the sensitivity coefficient of the input (specified force) of the first intersection to the output (voltage) of the first intersection; 12 K represents the sensitivity coefficient of the input (specified force) of the first intersection to the output (voltage) of the second intersection; 21 K represents the sensitivity coefficient of the input (specified force) of the second intersection to the output (voltage) of the first intersection; 22 It represents the sensitivity coefficient of the input (specified force) of the second intersection to the output (voltage) of the second intersection.

[0064] In essence, the output U1 of the first intersection = the effect of the first intersection input (F1) on the output of the first intersection + the effect of the second intersection input (F2) on the first intersection, and is expressed by the following expression:

[0065] U1=F1×K 11 +F2×K 21 (5)

[0066] The output of the first intersection is the same as that of the pantograph slide to be tested. 11 , K 12 , K 21 and K 22 , we need to solve four known equations with four unknown coefficients. Applying weights at any point can result in two equations, so calibration is required twice.

[0067] In principle, any point can be subjected to a specified force. This is because the force acting on any point can be decomposed into the component forces at the pressure sensors at the two intersections in the pantograph slide to be tested. For the sake of simplicity in calculation, the weight can be placed on one sensor (i.e., a specified force is applied to the first intersection alone). At this time, the force on the sensor at the first intersection is F, and the force on the sensor at the other intersection is 0. Figure 4 shown.

[0068] When a specified force (for example, hanging a weight) is applied at the first intersection, we have:

[0069] U 11 =F*K 11 +0*K 21 (6)

[0070] U 12 =F*K 12 +0*K 22 (7)

[0071] When a specified force (for example, hanging a weight) is applied at the first intersection, we have:

[0072] U 21 =0*K 11 +F*K 21 (8)

[0073] U 22 =0*K 12 +F*K 22 (9)

[0074] Thus, the force matrix can be obtained as:

[0075] F M ×K M =U M (10)

[0076] In this way, the above expression (4) is derived.

[0077] After pressure calibration is completed (i.e., the sensitivity coefficient matrix is ​​calculated), the process proceeds to step S320. The sensitivity coefficient matrix constructed by the present invention considers the mutual influence of the forces on each sensor when the force is applied at different intersections, thereby calculating the contribution of each sensor to the force in turn.

[0078] In the actual application process of the pantograph to be tested, step S320 obtains the actual contact pressure of all pressure sensors in the pantograph to be tested according to the real-time voltage of the pantograph to be tested at each intersection and the sensitivity coefficient matrix constructed in step S310.

[0079] In step S320, first, according to the real-time voltage at each intersection in the pantograph to be tested, the voltage variation at the corresponding intersection is obtained, and the sensor dynamic output voltage matrix is ​​constructed. The sensor dynamic output voltage matrix can be: U t-r =[U t-1 U t-2 ],U t-r represents the real-time output voltage matrix of the sensor at time t, U t-1 represents the voltage change at the first intersection at time t, U t-2 represents the voltage change at the second intersection at time t.

[0080] Then, according to the above-constructed sensor dynamic output voltage matrix, the inverse matrix of the sensitivity coefficient matrix obtained in step S310 is used to calculate the dynamic contact pressure matrix F representing the real-time contact pressure at each intersection. t-r Among them, each element in the dynamic contact pressure matrix represents the real-time contact pressure exerted on the sensor at different intersection positions.

[0081] In one embodiment, the dynamic contact pressure matrix is ​​expressed as follows:

[0082]

[0083] Among them, F t-r represents the dynamic contact pressure matrix.

[0084] In addition, based on the above calibration method, an embodiment of the present invention further provides a calibration system for a pantograph-catenary contact pressure sensor.

[0085] Figure 5 FIG. 1 is a schematic diagram of the structure of a calibration system for a pantograph-catwalk contact pressure sensor according to an embodiment of the present application. Figure 5 As shown, the calibration system described in the embodiment of the present invention includes: a pressure sensor 501, a specified force applying unit 502 and a data management and analysis module 503.

[0086] A corresponding pressure sensor 501 is provided at each intersection of the slide plate and the bracket of the pantograph to be tested. The number of pressure sensors 501 is preferably two. Each pressure sensor 501 is used to measure the voltage at each intersection when a specified force is applied to different intersections separately each time during the pressure calibration stage.

[0087] The specified force applying unit 502 is used to apply a specified force to each pressure sensor 501. In one embodiment, the specified force applying unit 502 is implemented by hanging a weight.

[0088] The data management and analysis module 503 is used to obtain the sensitivity coefficient matrix of all intersection pressure sensors according to the applied specified force and the voltage of each intersection when the force is applied each time. The data management and analysis module 503 is also used to obtain the actual contact pressure of the pressure sensor according to the real-time voltage of the pantograph at each intersection during the actual application of the pantograph to be tested, using the constructed sensitivity coefficient matrix.

[0089] The present invention discloses a calibration method and system for bow-net contact pressure sensors. The method and system simultaneously observe the output of each sensor under load conditions, determine each sensitivity through tests at different load-bearing points, take into account the mutual influence between each sensor, and comprehensively consider the contribution of each sensor to the force, and use a new calibration method to calculate the sensitivity coefficient of each sensor itself and each other, so as to obtain a more accurate calibration calculation result. In addition, the sensitivity coefficient obtained by performing calibration experiments on each load-bearing point in advance is input into the bow-net relationship detection, so that the bow-net contact pressure of the entire line can be calculated in real time, and the bow-net relationship can be evaluated. In this way, the present invention considers the mutual influence of the forces on each sensor when the force is applied at different points, calculates the contribution of each sensor to the force in turn, and calibrates the sensitivity coefficient of each sensor. It considers more factors and the calculation results are more accurate.

[0090] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any person familiar with the technology within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0091] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0092] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0093] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0094] The "one embodiment" or "embodiment" mentioned in the specification means that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment" or "embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0095] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A calibration method for a pantograph-catenary contact pressure sensor, characterized in that: include: Apply a force of a specified strength at each intersection of the slide plate and the bracket of the pantograph to be tested, measure the voltage of each intersection when the force is applied each time, and based on this, obtain the sensitivity coefficient matrix of the pressure sensors at all intersections; When applied, the actual contact pressure of the pressure sensor is obtained according to the real-time voltage of the pantograph to be tested at each intersection using the sensitivity coefficient matrix.

2. The calibration method according to claim 1, characterized in that: The process of generating the sensitivity coefficient matrix includes: According to the strength and application position of the specified force applied at each intersection, a force matrix about the pantograph to be tested is constructed; According to the voltage at each intersection when the force is applied each time, constructing a sensor output voltage matrix of the pantograph to be tested; The sensitivity coefficient matrix is ​​obtained according to the force matrix and the sensor output voltage matrix.

3. The calibration method according to claim 2, characterized in that: In the process of constructing the force matrix, The rows of the matrix represent the number of times the specified force is applied to the corresponding intersection position individually, and the columns of the matrix represent the amplitude of the force applied to each intersection, wherein the force amplitude of the intersection that is not subjected to the specified force is zero by default.

4. The calibration method according to claim 3, characterized in that: In the process of constructing the sensor output voltage matrix, The rows of the matrix represent the number of times the specified force is applied to the corresponding intersection position, and the columns of the matrix represent the voltage change at each intersection.

5. The calibration method according to any one of claims 2 to 4, characterized in that: The step of obtaining the sensitivity coefficient matrix according to the force matrix and the sensor output voltage matrix includes: The inverse matrix of the force matrix is ​​first calculated, and then the sensitivity coefficient matrix is ​​obtained by calculating the product matrix of the inverse matrix of the force matrix and the sensor output voltage matrix.

6. The calibration method according to claim 4, characterized in that: When there are two intersection points between the slide plate and the bracket of the pantograph to be tested, the force matrix is: Among them, F M represents the force matrix, F represents the amplitude of the specified force, and the sensor output voltage matrix is: Among them, U M represents the sensor output voltage matrix, U 11 , U 12 They represent the voltage changes of the two intersections when the specified force is applied to the first intersection alone, U 21 , U 22 They respectively represent the voltage changes of the two intersections when the specified force is applied to the second intersection alone.

7. The calibration method according to claim 5, characterized in that: The sensitivity coefficient matrix is ​​calculated using the following expression: Among them, K M represents the sensitivity coefficient matrix, F M represents the force matrix, U M Represents the sensor output voltage matrix.

8. The calibration method according to any one of claims 1 to 7, characterized in that: The step of obtaining the actual contact pressure of the pressure sensor by using the sensitivity coefficient matrix according to the real-time voltage of the pantograph to be tested at each intersection includes: According to the real-time voltage at each intersection, the voltage change at the corresponding intersection is obtained, and the dynamic output voltage matrix of the sensor is constructed; According to the dynamic output voltage matrix of the sensor and using the inverse matrix of the sensitivity coefficient matrix, a dynamic contact pressure matrix representing the real-time contact pressure at each intersection is calculated.

9. The calibration method according to any one of claims 1 to 8, characterized in that: The direction of the force applied to each intersection individually is vertically downward, wherein the process of applying the specified force is simulated by sequentially hanging weights having the same strength as the specified force at each intersection.

10. A calibration system for a pantograph-catenary contact pressure sensor, characterized in that: The calibration system is used to implement the calibration method according to any one of claims 1 to 9, wherein the calibration system comprises: Pressure sensor, wherein a corresponding pressure sensor is provided at each intersection of the slide plate and the bracket of the pantograph to be tested, and each pressure sensor is used to measure the voltage at each intersection when a specified force is applied to a different intersection each time; a designated force applying unit for applying a designated force to each pressure sensor respectively; and A data management and analysis module is used to obtain the actual contact pressure of the pressure sensor based on the sensitivity coefficient matrix of all intersection pressure sensors according to the applied specified force and the voltage of each intersection when the force is applied each time. During the actual application of the pantograph to be tested, the actual contact pressure of the pressure sensor is obtained according to the real-time voltage of the pantograph to be tested at each intersection by using the sensitivity coefficient matrix.

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