Monitoring system for a pantograph, optical fiber sensor

Abstract

A monitoring system of a pantograph, a fiber sensor, the system comprises: one or more fiber sensors, the fiber sensor is installed on the pantograph, and is used for receiving a laser signal; a processor is coupled with the fiber sensor, and is used for processing a signal collected by the fiber sensor; wherein the fiber sensor has an optical interference cavity, the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and a cavity length of the optical interference cavity satisfies a formula: the present application can avoid signal interference of adjacent wave peaks on the wave peak in the data analysis process, and effectively prevents code stringing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measurement, in particular to a monitoring system of a pantograph and an optical fiber sensor. BACKGROUND

[0002] With the continuous increase of urbanization rate in China, the population flow to the city causes the sudden increase of urban population, and the traffic pressure continues to increase. Compared with other urban transportation modes, rail transit is the most efficient in public transportation mode, and is one of the best ways to solve the urban travel problem. The rail transit represented by high-speed railway and urban subway has become the main means of transportation for people, and the domestic high-speed rail market will gradually improve under the planning of "eight vertical and eight horizontal", and there will be higher demand for high-speed rail vehicles (such as electric passenger cars).

[0003] Specifically, the high-frequency crowd-intensive travel brings serious challenges to the operation safety of the rail transit industry, among which the good working state of the pantograph of the electric passenger car, the working state of the contact line, and the current collection relationship between the pantograph and the contact line are the most important for the operation safety of the electric passenger car.

[0004] However, in an existing monitoring technology, a machine vision sensor is used to monitor the state of the pantograph and the contact line, which has low accuracy and high failure rate.

[0005] In another existing monitoring technology, an electronic sensor is used to monitor the state of the pantograph and the contact line, but due to its large size, large volume and heavy weight, it can easily affect the normal operation of the pantograph. In addition, since the electronic sensor is an active device, the signal transmission cable has safety hazards, and improper installation, wiring process or mechanical damage by external force can cause serious electrical insulation accidents, even the high voltage on the car roof can be introduced to threaten the safety of personnel, and the collected signals are often seriously interfered by electromagnetic interference, which brings great difficulties to the subsequent accurate analysis of data.

[0006] Therefore, there is an urgent need for a monitoring system of a pantograph based on a monitoring element with smaller volume and lighter weight to collect monitoring parameters, thereby avoiding affecting the normal operation of the pantograph and improving the accuracy of real-time collection, analysis and feedback of operation parameters related to the pantograph, the contact line and the pantograph-catenary relationship. SUMMARY

[0007] The technical problem solved by the present application is to provide a monitoring system of a pantograph and an optical fiber sensor, which can avoid the signal interference of adjacent wave peaks on the wave peak in the data analysis process and effectively prevent code stringing.

[0008] To solve the above technical problems, the embodiment of the present application provides a monitoring system of a pantograph, comprising: one or more optical fiber sensors, the optical fiber sensors are installed on the pantograph and used for receiving a laser signal; a processor, which is coupled with the optical fiber sensors and used for processing signals collected by the optical fiber sensors; wherein the optical fiber sensor has an optical interference cavity, the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and the cavity length of the optical interference cavity satisfies the following formula:

[0009]

[0010]

[0011] wherein, l FP represents the cavity length of the optical interference cavity, k mid represents a preset longitudinal mode number of the optical fiber sensor, k mid is a positive integer, and k mid ≥2, W laser represents the bandwidth of a laser used for emitting the laser signal, and λ ctr represents the center wavelength value of the bandwidth of the laser; the optical interference cavity comprises mirrors located at both ends of the cavity, and the cavity length of the optical interference cavity is the spacing between the two mirrors.

[0012] Optionally, the cavity length of the optical interference cavity satisfies the following formula:

[0013]

[0014] wherein, l ctr represents the cavity length of the optical interference cavity.

[0015] Optionally, the optical fiber sensor is a passive sensor.

[0016] Optionally, the optical fiber sensor comprises at least one contact force sensor used for collecting a pressure signal, the pantograph comprises one or more pantograph heads, each pantograph head comprises a pantograph head support; for the pantograph head provided with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support.

[0017] Optionally, the contact force sensors are arranged in pairs, and the contact force sensors arranged in pairs are respectively installed on the pantograph head supports at both ends of the same pantograph head.

[0018] Optionally, the pantograph head supports and the contact force sensors are in one-to-one correspondence, and each pantograph head support has a corresponding contact force sensor installed inside or on the surface thereof.

[0019] Optionally, the contact force sensor is internally embedded with a temperature sensor, or the contact force sensor is coupled with a temperature sensor.

[0020] Optionally, the pressure signal is used to indicate the mass of the carbon strip structure of the pantograph; the processor determines the abrasion amount of the carbon strip structure by using the following formula:

[0021]

[0022]

[0023] ΔG 0,i (t)=G' 0,i (t)-G 0,i

[0024] wherein, G 0,i represents the initial mass of the i-th group of carbon strip structures when not abraded, G' 0,i (t) represents the mass of the i-th group of carbon strip structures at time t, K G,i,j represents the contact force coefficient of the j-th contact force sensor of the i-th group of carbon strip structures, λ D,i,j represents the wavelength value of the j-th contact force sensor of the i-th group of carbon strip structures in the state of no force, λ CS,i,j represents the wavelength value of the j-th contact force sensor of the i-th group of carbon strip structures when the i-th group of carbon strip structures is not abraded, λ' CS,i,j represents the wavelength value of the j-th contact force sensor of the i-th group of carbon strip structures at time t, N S represents the number of contact force sensors on the same group of carbon strip structures, i represents the serial number of the carbon strip structure, and j represents the serial number of the contact force sensor of each carbon strip structure.

[0025] Optionally, the pressure signal is used to indicate the pantograph-pantograph contact force between the pantograph head and the contact wire; the processor determines the pantograph-pantograph contact force between the pantograph head and the contact wire by using the following formula:

[0026] F S,i,j (t)=K S,i,j [λ i,j (t)-λ 0,i,j +k T,i,j (T(t)-T0)]

[0027]

[0028] wherein, F S,i,j (t) represents the contact force value between the contact force sensor on the j-th pantograph head support of the i-th group of carbon strip of the pantograph head and the contact wire at time t, KS,i,j λij(t) is the contact force coefficient of the jth contact force sensor of the ith carbon slide plate i,j (t) is the wavelength value of the jth contact force sensor of the ith carbon slide plate at time t, λ 0,i,j kij is the wavelength value of the jth contact force sensor of the ith carbon slide plate when the pantograph head has no interaction with the contact wire, k T,i,j Tij is the temperature drift coefficient of the jth contact force sensor of the ith carbon slide plate, T(t) is the temperature value at time t, T0 is the temperature value at the initial time, F cp (t) is the contact force value between the pantograph head and the contact wire at time t, N C N is the number of carbon slide plates on the pantograph head S N is the number of carbon slide plates on the pantograph head

[0029] Optionally, the optical fiber sensor comprises at least one acceleration sensor for collecting acceleration signals, the pantograph comprises one or more pantograph heads, each pantograph head comprises carbon slide plates, pantograph head supports respectively connected to two ends of the carbon slide plates, and connecting components for connecting the carbon slide plates and the respective pantograph head supports; for the pantograph head provided with the acceleration sensor, the acceleration sensor is installed at one or more of the following positions: the inside or surface of the pantograph head support, and the connecting component.

[0030] Optionally, the acceleration sensors are arranged in pairs; wherein the acceleration sensors in each pair are respectively installed on the pantograph head supports at the two ends of the same pantograph head, or the acceleration sensors in each pair are respectively installed on the connecting components at the two ends of the same pantograph head.

[0031] Optionally, the pantograph head supports and the acceleration sensors are in one-to-one correspondence, and each pantograph head support has a corresponding acceleration sensor installed inside or on the surface thereof.

[0032] Optionally, the acceleration sensor is an optical fiber three-axis acceleration sensor.

[0033] Optionally, the acceleration sensor has a current sensor embedded therein, or the acceleration sensor is coupled with a current sensor.

[0034] Optionally, the acceleration signals are used to indicate the acceleration of at least one pantograph head in the lateral direction and the acceleration of at least one pantograph head in the vertical direction; and the processor determines the vertical and lateral vibration displacements of the pantograph head by using the following formula:

[0035]

[0036]

[0037] wherein d H (t) is used to represent the displacement value of the pantograph head in the lateral direction at time t, d 0,H is used to represent the initial displacement value of the pantograph head in the lateral direction, v 0,H is used to represent the initial velocity value of the pantograph head in the lateral direction, a H (t) is used to represent the acceleration value of the pantograph head in the lateral direction at time t, d V (t) is used to represent the displacement value of the pantograph head in the vertical direction at time t, d 0,V is used to represent the initial displacement value of the pantograph head in the vertical direction, v 0,V is used to represent the initial velocity value of the pantograph head in the vertical direction, a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t.

[0038] Optionally, the optical fiber sensor further comprises at least one contact force sensor to collect a pressure signal, the pantograph comprises one or more pantograph heads, each pantograph head comprises a pantograph head support; for the pantograph head installed with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support; the pressure signal is used to indicate the pantograph-catenary contact force between the pantograph head and the contact wire; the acceleration signal is used to indicate the acceleration of at least one pantograph head in the lateral direction and the acceleration of at least one pantograph head in the vertical direction; the processor determines the acceleration value of the pantograph head in the vertical direction and the pantograph-catenary contact force between the pantograph head and the contact wire by using the following formula:

[0039] a V (t) = K V [λ V (t) - λ 0,V +k T,V (T(t) - T0)]

[0040] F S (t) = K S [λ S (t) - λ 0,S +k T,S (T(t) - T0)]

[0041] wherein a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t, K V is used to represent the acceleration coefficient of the acceleration sensor in the vertical direction, λ V (t) is used to represent the wavelength value of the acceleration sensor in the vertical direction at time t, λ 0,V is used to represent the wavelength value of the acceleration sensor in the vertical direction in the static state, k T,VF is used to represent the temperature drift coefficient of the acceleration sensor in the vertical direction S (t) is used to represent the contact force value between the contact force sensor and the contact wire at time t, K S λ is used to represent the contact force coefficient of the contact force sensor S (t) is used to represent the wavelength value of the contact force sensor at time t, λ0, S k is used to represent the wavelength value of the contact force sensor when the pantograph head has no interaction with the contact wire T,S T is used to represent the temperature drift coefficient of the contact force sensor, T(t) is used to represent the temperature value T at time t, and T0 is used to represent the temperature value at the initial time.

[0042] Optionally, the optical fiber sensor further comprises at least one contact force sensor for collecting a pressure signal, the pantograph comprises one or more pantograph heads, each pantograph head comprises a pantograph head support; for the pantograph head installed with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support; the pressure signal is used to indicate the pantograph-catenary contact force between the pantograph head and the contact wire; the acceleration signal is used to indicate the acceleration of at least one pantograph head in the longitudinal direction; the processor determines the pull-out value of the contact wire by using the following formula:

[0043]

[0044] Or

[0045]

[0046]

[0047]

[0048] Wherein, Z C (t) is used to represent the pull-out value of the contact wire at time t, Z C is negative, Z C is positive, L S is the distance between the centers of the pantograph head supports with buffer or / and damping systems at both ends of the same group of carbon slides, F S,i,drg and F S,i,gch are respectively used to represent the contact force value between the contact force sensor on the right and left pantograph head supports of the i-th group of carbon slides of the pantograph head and the contact wire at time t, v L (t) is used to represent the speed value of the pantograph head in the longitudinal direction at time t, v 0,L is used to represent the initial speed value of the pantograph head in the longitudinal direction, a L (t) is used to represent the acceleration value of the pantograph head in the longitudinal direction at time t, aL , D L (t) is used to represent the running distance of the train at time t, D 0,L is used to represent the initial running distance of the train.

[0049] Optionally, the acceleration signal is used to indicate the acceleration of the at least one pantograph head in the vertical direction; the processor determines the height of the contact wire using the following formula:

[0050]

[0051]

[0052] wherein v V (t) is used to represent the speed value of the pantograph head in the vertical direction at time t, v 0,V is used to represent the initial speed value of the pantograph head in the vertical direction, a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t, h C (t) is used to represent the height of the contact wire at time t, h Tr is used to represent the height of the roof of the car in which the pantograph is located relative to the ground level, h cp,0 (P A,0 ) is used to represent the height of the upper surface of the carbon slide of the pantograph head relative to the roof when the pressure value of the air bag / cylinder is P A,0 A,0 is used to represent the pressure value of the air bag / cylinder in the static lifting state when the pantograph is in the normal current collection state.

[0053] Optionally, the optical fiber sensor comprises at least one temperature sensor for collecting a temperature signal, the pantograph comprises one or more pantograph heads, each pantograph head comprises a carbon slide, a pantograph support connected to both ends of the carbon slide respectively, and a connecting component for connecting the carbon slide and the respective pantograph support; for the pantograph head provided with the temperature sensor, the temperature sensor is installed at one or more of the following positions: the inside or surface of the pantograph support, and the connecting component.

[0054] Optionally, the optical fiber sensor comprises at least one current sensor for collecting a current signal, the pantograph comprises one or more pantograph heads, each pantograph head comprises a carbon slide, a pantograph support connected to both ends of the carbon slide respectively, and a connecting component for connecting the carbon slide and the respective pantograph support; for the pantograph head provided with the current sensor, the current sensor is installed at one or more of the following positions: the inside or surface of the pantograph support, and the connecting component.

[0055] ​Optionally, the optical fiber sensor comprises at least one load sensor for collecting a load signal, and the pantograph comprises a four-bar linkage structure; the load sensor is installed at one or more of the following positions: an upper arm of the four-bar linkage structure, a lower arm of the four-bar linkage structure, and a lower guide rod of the four-bar linkage structure.

[0056] Optionally, the load sensor is internally embedded with a temperature sensor, or the load sensor is coupled with a temperature sensor.

[0057] Optionally, the load sensor is installed on the same cross-sectional circumference of any cross section of the lower guide rod, and the load signal is used to indicate the tension of the lower guide rod; the processor determines the tension value of the lower guide rod by using the following formula:

[0058]

[0059] wherein F pf (t) represents the tension value of the lower guide rod at time t, N represents the total number of load sensors on the same cross section of the lower guide rod, K pf,n represents the tension coefficient of the nth optical fiber load sensor, λ n (t) represents the wavelength value of the nth load sensor at time t, λ 0,n represents the wavelength value of the nth optical fiber load sensor under no load, k T,n represents the temperature drift coefficient of the nth optical fiber load sensor, T(t) represents the temperature value at time t, and T0 represents the temperature value at the initial time.

[0060] Optionally, the load sensors are installed in pairs on the same cross-sectional circumference of any cross section of the lower guide rod, and the paired load sensors are centrally symmetric, and the load signal is used to indicate the bending moment of the lower guide rod; the processor determines the bending moment value of the lower guide rod by using the following formula:

[0061] M i,i-opp (t) = K M,i {λ i (t) - λ 0,i +k T,i [T(t) - T0]} - K M-opp,i-opp {λ opp,i-opp (t) - λ 0-opp,i-opp +k T-opp,i-opp [T(t) - T0]}

[0062] wherein i = 1, 2, 3, …, I,

[0063] wherein M i,i-opp(t) is used to represent the bending moment value of the lower guide rod at the i, i-opp bending direction at time t, N is used to represent the total number of load sensors on the same cross section of the lower guide rod, I is used to represent the pairing number of two load sensors on the same cross section of the lower guide rod, K M,i is used to represent the bending moment coefficient of the i-th load sensor of the lower guide rod, λ i (t) is used to represent the wavelength value of the i-th fiber load sensor at time t, λ 0,i is used to represent the wavelength value of the i-th fiber load sensor under no load, k T,i is used to represent the temperature drift coefficient of the i-th fiber load sensor, K M-opp,i-opp is used to represent the bending moment coefficient of the fiber load sensor opposite to the i-th fiber load sensor of the lower guide rod, λ opp,i-opp (t) is used to represent the wavelength value of the i-opp fiber load sensor opposite to the i-th fiber load sensor at time t, λ 0-opp,i-opp is used to represent the wavelength value of the i-opp fiber load sensor opposite to the i-th fiber load sensor under no load, k T-opp,i-opp is used to represent the temperature drift coefficient of the i-opp fiber load sensor opposite to the i-th fiber load sensor, T(t) is used to represent the temperature value at time t, T0 is used to represent the temperature value at the initial time.

[0064] Optionally, the fiber sensor comprises at least one strain sensor for collecting a deformation signal, and the pantograph comprises a four-bar linkage structure and a chassis; the strain sensor is installed at one or more of the following: an upper arm of the four-bar linkage structure, a lower arm of the four-bar linkage structure, a lower guide rod of the four-bar linkage structure, and the chassis.

[0065] Optionally, the fiber sensor comprises at least one air pressure sensor for collecting an air pressure signal, and the pantograph comprises an air bag and / or an air cylinder, a pneumatic control box, and an air path pipeline connected to the pneumatic control box; the air pressure sensor is installed at one or more of the following: the air bag and / or the air cylinder, the inside or surface of the pneumatic control box, and the air path pipeline.

[0066] Optionally, the air pressure sensor is internally embedded with a temperature sensor, or the air pressure sensor is coupled with a temperature sensor.

[0067] Optionally, the air pressure signal is used to indicate the air pressure value in the air bag or the air cylinder of the pantograph; the processor determines the air pressure value in the air bag or the air cylinder of the pantograph by using the following formula:

[0068] P A (t) = K A [λ(t) - λ0 + kT (T(t)-T0)]

[0069] Among them, P A (t) represents the pressure value of the airbag / cylinder at time t, K A The pressure coefficient of the air pressure sensor is used to represent the pressure coefficient, λ(t) is used to represent the wavelength value of the air pressure sensor at time t, λ0 is used to represent the wavelength value of the air pressure sensor when the airbag / cylinder is not inflated, and k T The temperature drift coefficient of the pressure sensor is used to represent the temperature value at time t, and T0 is used to represent the temperature value at the initial time.

[0070] Optionally, the pantograph is selected from: spring box pantograph, leaf spring pantograph, and tension spring pantograph.

[0071] Optionally, the installation method of the fiber optic sensor can be selected from: screw fastening, embedding, welding, gluing and implantation.

[0072] Optionally, the processor includes an FPGA and a multiplex analog-to-digital converter module; wherein the FPGA is used to control the multiplex analog-to-digital converter module to complete analog-to-digital signal conversion and spectral analysis, and output the wavelength values ​​of each fiber optic sensor.

[0073] To address the aforementioned technical problems, this invention provides an optical fiber sensor for receiving laser signals. The optical fiber sensor includes an optical interference cavity, where the laser signal enters the optical interference cavity to form a comb-shaped spectrum. The cavity length of the optical interference cavity satisfies the following formula:

[0074]

[0075]

[0076] Among them, l FP k is used to represent the cavity length of the optical interference cavity. mid The preset longitudinal mode number, k, is used to represent the optical fiber sensor. mid The value of k is a positive integer, and k mid ≥2, W laser λ is used to represent the bandwidth of the laser that emits the laser signal. ctr The optical interference cavity is used to represent the center point wavelength value of the bandwidth of the laser; the optical interference cavity includes mirrors located at both ends of the cavity, and the cavity length of the optical interference cavity is the distance between the two mirrors.

[0077] Optionally, the cavity length of the optical interference cavity satisfies the following formula:

[0078]

[0079] wherein, l ctr for representing a cavity length of the optical interference cavity.

[0080] Compared with the prior art, the technical scheme of the embodiment of the present application has the following beneficial effects:

[0081] In the embodiment of the present application, according to the bandwidth of the laser device emitting the laser signal, the center point wavelength value of the bandwidth of the laser device and the preset longitudinal mode number of the optical fiber sensor, the cavity length of the optical interference cavity can be determined by using a formula, so that only a single wave peak in the comb-shaped spectrum output from the optical interference cavity is located within the bandwidth of the laser device, thereby avoiding signal interference of adjacent wave peaks on the wave peak in the data analysis process and effectively preventing code stringing. Further, based on the above cavity length limitation, a small-size and small-volume optical fiber sensor can be formed, thereby facilitating the manufactured sensor chip to realize compact structure and lighter quality on the basis of maintaining good parameter consistency, high sensitivity, large dynamic range, good linearity, stable performance, strong reliability and the like. The monitoring system of the pantograph can realize multi-directional monitoring, real-time accurate collection, analysis and feedback of operation parameters related to the pantograph, the contact wire and the pantograph-catenary relationship.

[0082] Further, by setting the cavity length of the optical interference cavity to satisfy the cavity length formula, not only a single wave peak in the comb-shaped spectrum output from the optical interference cavity is located within the bandwidth of the laser device, but also the wave peak is located at the center position of the bandwidth of the laser device, thereby more easily avoiding signal interference of adjacent wave peaks on the wave peak in the analysis process, further effectively preventing code stringing and further realizing full optical bandwidth measurement of the laser device when the wave peak is located at the center position of the bandwidth of the laser device.

[0083] Further, the optical fiber sensor is a passive sensor, and by using the passive sensor, passive detection of the detection end without electricity can be realized, the electromagnetic resistance can be effectively improved, the danger to passengers of the passenger train caused by power supply can be avoided, the electrification accident can be prevented, the interference caused by detection can be avoided, the normal monitoring can be ensured and the detection accuracy can be improved.

[0084] Further, for the pantograph head provided with the contact force sensor, by setting at least one contact force sensor to be installed in the interior or on the surface of the pantograph head support, the contact wire hard point, the pull-out value, the contact force between the pantograph and the catenary, the impact and the arcing can be monitored.

[0085] Further, the contact force sensors are arranged in pairs, and the pairs of contact force sensors are respectively installed on the bow head supports at the two ends of the same bow head, so as to monitor the contact force between the pantograph and the catenary, the wear amount, wear area and eccentric wear of the carbon slide plate of the pantograph.

[0086] Further, the bow head supports correspond to the contact force sensors one by one, and the corresponding contact force sensors are installed on the inside or surface of each bow head support, so as to monitor all the bow heads and avoid leaving hidden dangers due to missed detection.

[0087] Further, for the bow head provided with the acceleration sensor, the acceleration sensor is installed at one or more of the following positions: the inside or surface of the bow head support, the connecting component, so as to monitor the hard point of the contact wire, the impact and the height value, and effectively distinguish the flexible wire and the rigid wire.

[0088] Further, the acceleration sensors are arranged in pairs, and the pairs of acceleration sensors are respectively installed on the bow head supports at the two ends of the same bow head, or the pairs of acceleration sensors are respectively installed on the connecting components at the two ends of the same bow head, so as to effectively monitor the stability of the same bow head by using the acceleration signals at the two ends of the same bow head.

[0089] Further, for the bow head provided with the temperature sensor, the temperature sensor is installed at one or more of the following positions: the inside or surface of the bow head support, the connecting component, so as to monitor the arc between the pantograph and the catenary according to the temperature signal.

[0090] Further, for the bow head provided with the current sensor, the current sensor is installed at one or more of the following positions: the inside or surface of the bow head support, the connecting component, so as to monitor the arc between the pantograph and the catenary according to the current signal.

[0091] Further, the load sensors are installed at one or more of the following positions of the four-bar linkage: the upper arm, the lower arm and the lower guide rod, so as to monitor the tension and bending moment of the upper arm, the lower arm and the lower guide rod, and further, the load sensor arranged on the lower guide rod can also be used to monitor the jamming of the connecting shaft at the two ends of the lower guide rod.

[0092] Further, the strain sensors are installed at one or more of the following positions: the upper arm of the four-bar linkage structure, the lower arm of the four-bar linkage structure, the lower guide rod of the four-bar linkage structure and the chassis, so as to monitor the fatigue degree of the upper arm of the four-bar linkage structure, the lower arm of the four-bar linkage structure, the lower guide rod of the four-bar linkage structure and the chassis according to the deformation signal.

[0093] Further, the air pressure sensors are installed at one or more of the following positions: the air bag and / or air cylinder, the inside or surface of the pneumatic control box, and the air path pipeline, so as to monitor the pressure of the air bag or air cylinder of the pantograph according to the air pressure signal, and monitor the failure of the lifting pantograph.

[0094] Further, the processor comprises an FPGA and a multi-channel analog-digital conversion module; wherein the FPGA is used to control the multi-channel analog-digital conversion module to complete analog-digital signal conversion and spectrum analysis, and output wavelength values of each optical fiber sensor. Compared with using a digital signal processor to collect and process signals, the FPGA can only be applied to multi-condition processes and multi-algorithm tasks under a lower sampling rate or a low data rate of a system. The FPGA can collect and process high data rate signals (such as Gbps signals or even higher data rates) that the digital signal processor cannot handle. In this way, the FPGA can better collect and process massive sampling data at the same time caused by multi-channel synchronous scanning of a high-speed scanning laser, and can directly output wavelength values. The wavelength value is a wavelength value at which the optical intensity of a comb-shaped spectrum output by the optical fiber sensor is maximum within the bandwidth of the laser. Since only a single wave peak of the comb-shaped spectrum output by the optical fiber sensor in the application is within the bandwidth of the laser, only a single wavelength value at which the optical intensity is maximum is used for output. BRIEF DESCRIPTION OF DRAWINGS

[0095] Figure 1 FIG. 1 is a structural schematic diagram of a monitoring system of a pantograph in an embodiment of the application;

[0096] Figure 2 FIG. 5 is a structural schematic diagram of an optical interference cavity in an optical fiber sensor in an embodiment of the application;

[0097] Figure 3 FIG. 8 is a schematic diagram of a spectrum output from the optical interference cavity in an embodiment of the application;

[0098] Figure 4 FIG. 11 is a schematic diagram of an installation position of an optical fiber sensor in a monitoring system on a pantograph in an embodiment of the application;

[0099] Figure 5 FIG. 14 is a schematic diagram of abrasion amount of a carbon slide plate changing with time in an embodiment of the application;

[0100] Figure 6 FIG. 17 is a time-domain schematic diagram of contact force between a pantograph head and a pantograph net perceived by a contact force sensor at one end of a carbon slide plate in an embodiment of the application;

[0101] Figure 7 FIG. 20 is a time-domain schematic diagram of contact force between a pantograph head and a pantograph net perceived by a contact force sensor at the other end of a carbon slide plate in an embodiment of the application;

[0102] Figure 8 FIG. 23 is a time-domain schematic diagram of vertical acceleration value of a pantograph head perceived by an acceleration sensor on the pantograph head in an embodiment of the application;

[0103] Figure 9is a time-domain variation diagram of a contact line pull-out value of a carbon slide plate in a driving state in an embodiment of the present application;

[0104] Figure 10 is a time-domain diagram of a contact line guide height value in a driving state in an embodiment of the present application;

[0105] Figure 11 is a structural diagram of a four-bar linkage structure in an embodiment of the present application;

[0106] Figure 12 is a position diagram of a load sensor on a same circumferential section of a lower guide rod in an embodiment of the present application;

[0107] Figure 13 is a principle diagram of an optical fiber sensing analyzer of a monitoring system using a pantograph in an embodiment of the present application. DETAILED DESCRIPTION

[0108] As described above, the pantograph working state, the contact line working state, and the current collection relationship between the pantograph and the contact line are the most important for the vehicle operation safety, and need to be effectively monitored. Specifically, the monitoring can be derived from the following contents:

[0109] a. Regarding the pantograph working state: when the vehicle (such as an electric passenger car) is driving, if the pantograph head gravity center is unbalanced or the rotation is not flexible, the carbon slide plate on the pantograph will be abnormally worn; if the hinge system composed of the bearings at both ends of the lower guide rod of the pantograph is stuck, the four-bar linkage mechanism of the pantograph will lose the function of dynamically adjusting the pantograph head height and balance, and there is a risk of the lower guide rod being broken; if the air bag or air cylinder of the pantograph appears air path blockage or escape, etc., the pantograph will not be able to be lifted or will not be able to maintain the current collection height after being lifted, etc., which will cause the contact force between the pantograph and the contact line to be abnormal, and the carbon slide plate and the contact line surface will be excessively worn, or the arcing between the pantograph and the contact line will occur.

[0110] b. Regarding the contact line working state: when the vehicle (such as an electric passenger car) is driving, the pantograph and the contact line are in contact at all times, so the pantograph in high-speed motion will cause the contact line to fluctuate, and the dynamic contact line pull-out value and guide height value are formed. If the geometric parameter indicators of the contact line, such as the pull-out value and the guide height value, exceed the design error on the vehicle driving route, it may cause abnormal wear of the carbon slide plate on the pantograph, or even cause the contact part of the contact line and the pantograph to deviate from the carbon slide plate to the horn area, and there is a risk of pantograph scraping the contact line. In addition, the unevenness of the contact line, and the contact line hard points generated by arcing will seriously impact the pantograph on the driving vehicle which is currently collecting current, and will cause the carbon slide plate on the pantograph to be burned, chipped and peeled, or even cause the pantograph to lose balance and even be severely damaged after being hit and separated from the roof of the vehicle.

[0111] c.The relationship between the pantograph and the contact wire: when a vehicle (such as an electric passenger car) is running at high speed, if the pressure between the pantograph and the contact wire is too large, the pantograph may break the contact wire or the contact wire may hit the pantograph; if the pressure is too small, the pantograph may not be able to collect electricity well, and even an arc may occur between the pantograph and the contact wire. Therefore, during the running of the train, there must be a reasonable contact force between the pantograph and the contact wire, so that the pantograph can safely introduce the current from the contact wire into the traction converter system in the vehicle body, thereby providing continuous and effective power for the vehicle.

[0112] However, in the existing monitoring technology, there are problems such as low accuracy, high error rate, and easy influence on the normal operation of the pantograph.

[0113] Specifically, with the popularization of unmanned metro technology in recent years and the rapid increase in passenger flow density, the traditional maintenance mode based on manual inspection cannot meet the real-time and safety requirements. Therefore, the rail transit industry gradually deepens the research on factors affecting the operation effect of the pantograph and contact wire, and with the continuous development of visual imaging technology, industrial cameras have been widely used in the field of vehicle-mounted pantograph operation measurement. The machine vision pantograph monitoring system has become the mainstream technology, which can measure the contact wire geometric parameters and pantograph operation parameters such as arc, and has a certain monitoring effect. However, from the application value and promotion benefit, there are still considerable limitations.

[0114] The inventors of the present application have found that, first of all, visual imaging is a non-contact measurement method, which cannot effectively detect and feedback the dynamic characteristics of the pantograph and contact wire (such as pantograph hard points and contact pressure), cannot realize real-time perception of pantograph body damage, component failure and operation abnormalities, cannot effectively measure the wear of the slide plate and the eccentric wear of the front and rear slide plates, and can only play a role in video review after the operation of most pantographs and contact wires.

[0115] Secondly, the machine vision pantograph monitoring system has special requirements for the vehicle type, roof space layout and internal cabinet, and a large amount of design coordination and drawing will be involved during installation, increasing the cost of vehicle modification. At the same time, in order to realize real-time video analysis and alarm for important operation parameters, high-cost hardware configuration and complex machine vision algorithms are required. At present, there are limited professional research personnel in this field in China, and many technical and application bottlenecks need to be broken through.

[0116] Finally, most of the visual sensor core components in the pantograph monitoring system created by industrial cameras rely on imports, are expensive, have a fast upgrade, and the service life and failure rate of electrical components often cannot meet the safety operation and maintenance cost requirements of rail transit vehicles. In order to ensure the shooting effect, fine daily maintenance is also required in the later stage.

[0117] In summary, from the comprehensive consideration of procurement cost, operation and maintenance cost, and actual monitoring effect, the machine vision method for monitoring the pantograph and pantograph-catenary system has low cost performance and insufficient accuracy.

[0118] On the passenger line detection vehicle and the freight line locomotive, electronic sensors are installed on the pantograph to obtain the contact force between the pantograph and the catenary, the pull-out value of the contact wire, and the height value of the guide, etc. by contact measurement. Compared with the machine vision pantograph-catenary monitoring system, it collects more complete operation parameters of the contact wire and the pantograph-catenary relationship, but cannot collect any parameters of the pantograph itself, so it is not widely applied to passenger vehicles due to the following main reasons:

[0119] a. The electronic sensor is seriously affected by electromagnetic interference, which brings great difficulties to subsequent data analysis;

[0120] b. The electronic sensor is not tailor-made for the pantograph, and may affect the normal operation of the pantograph due to size, volume, weight, etc.

[0121] c. The performance stability and service life of the electronic sensor do not meet the requirements of vehicle operation life cycle monitoring and operation management;

[0122] d. The signal transmission cable of the electronic sensor has safety hazards, and improper installation, wiring process or mechanical damage by external force may cause serious electrical insulation accidents, and even introduce high voltage on the vehicle roof to threaten personnel safety.

[0123] Referring to Table 1, Table 1 is a comparison table of measurement effects of electronic sensors and machine vision sensors.

[0124] Table 1

[0125]

[0126]

[0127] According to Table 1, a feasible monitoring technology and intelligent operation scheme are needed for safe operation of the vehicle to solve the bottleneck of the pantograph-catenary monitoring system in application value and promotion benefit.

[0128] In the embodiment of the present application, a monitoring system for a pantograph is provided, comprising: one or more optical fiber sensors installed on the pantograph for receiving a laser signal; a processor coupled to the optical fiber sensor for processing the signal collected by the optical fiber sensor; wherein the optical fiber sensor has an optical interference cavity, the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and the cavity length of the optical interference cavity satisfies a preset formula, and the optical interference cavity includes a mirror at both ends of the cavity, and the cavity length of the optical interference cavity is the distance between the two mirrors.

[0129] With the above scheme, the cavity length of the optical interference cavity can be determined according to the bandwidth of the laser that emits the laser signal, the center point wavelength value of the bandwidth of the laser, and the preset longitudinal mode number of the optical fiber sensor, so that only a single wave peak in the comb-shaped spectrum output from the optical interference cavity is located within the bandwidth of the laser, thereby avoiding signal interference of adjacent wave peaks on the wave peak in the analysis process and effectively preventing code stringing. Further, based on the above cavity length limitation, a small-size and small-volume optical fiber sensor can be formed, thereby facilitating the manufactured sensor chip to realize compact structure and lighter quality on the basis of maintaining good parameter consistency, high sensitivity, large dynamic range, good linearity, stable performance, strong reliability and the like. The sensor chip is helpful to be installed on the roof or inside of a vehicle (such as an electric passenger car), and compared with the electronic sensor in the prior art, the electronic sensor cannot be installed on the electric passenger car due to large volume and heavy weight, but can only be installed on a detection vehicle, an engineering vehicle or a freight locomotive. With the technical scheme in the embodiment of the present application, the monitoring system of the pantograph not only avoids affecting the normal operation of the pantograph, but also can realize multi-directional monitoring, real-time accurate collection, analysis and feedback of operation parameters related to the pantograph, the contact wire and the pantograph-catenary relationship.

[0130] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0131] Reference Figure 1 , Figure 1 is a structural schematic diagram of a monitoring system of a pantograph in an embodiment of the present application. The monitoring system of the pantograph can include a first optical fiber sensor 101, a second optical fiber sensor 102 to an Nth optical fiber sensor 103, and can further include a processor 110.

[0132] Among them, the first optical fiber sensor 101, the second optical fiber sensor 102 to the Nth optical fiber sensor 103 can be installed on the pantograph.

[0133] The processor 110 can be coupled with the first optical fiber sensor 101, the second optical fiber sensor 102 to the Nth optical fiber sensor 103, and the processor 110 is used to process the signals collected by the optical fiber sensor.

[0134] It should be pointed out that the processor 110 can also include a signal demodulation module (not shown in the figure), which demodulates and processes the first optical fiber sensor 101, the second optical fiber sensor 102 to the Nth optical fiber sensor 103.

[0135] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0136] The optical fiber sensor can have an optical interference cavity, the laser signal enters the optical interference cavity and outputs to form a comb-shaped spectrum, and the cavity length of the optical interference cavity satisfies the following formula:

[0137]

[0138]

[0139] Wherein, l FP The cavity length of the optical interference cavity is represented by k mid The preset longitudinal mode number of the optical fiber sensor is represented by k mid The value range of k mid ≥2, W laser The bandwidth of the laser that emits the laser signal is represented by λ ctr The center wavelength value of the bandwidth of the laser; the optical interference cavity includes mirrors at both ends of the cavity, and the cavity length of the optical interference cavity is the distance between the two mirrors.

[0140] With reference to Figure 2 And Figure 3 , Figure 2 is a structural diagram of an optical interference cavity in an optical fiber sensor in an embodiment of the application, Figure 3 is a spectrum output from the optical interference cavity in an embodiment of the application.

[0141] It can be understood that when a beam of light enters the optical interference cavity, the incident light and the reflected light interfere with each other, and after multiple reciprocating reflections on the two end mirrors, multiple beams of light will interfere to form a standing wave.

[0142] As Figure 2The optical interference cavity shown can include a mirror 21 and a cavity 22, the mirror 21 is located at both ends of the cavity, and the light waves are reflected back and forth via the mirror 21 to provide light energy feedback.

[0143] The cavity length of the optical interference cavity is the distance L between the two mirrors.

[0144] In one specific embodiment of the present application, the optical fiber sensor can include a probe head, and the probe head contains one or more optical interference cavities.

[0145] In Figure 3 In the spectrum diagram shown, the spectrum of the transmitted light or the inverse spectrum of the reflected light of the optical interference cavity forms a comb-shaped spectrum with a certain peak-to-peak distance, and the distance between the peaks is called the peak-to-peak distance.

[0146] Wherein, the spectrum output from the optical interference cavity can be a transmission spectrum or an inverse spectrum of a reflection spectrum, specifically, the spectrum output after transmission from the other side of the light source input side of the optical interference cavity (such as the right side without arrows in Figure 2 ) is a transmission spectrum, and the transmission spectrum is Figure 3 The comb-shaped spectrum shown with a certain peak-to-peak distance can be directly analyzed for the transmission spectrum; the spectrum output after reflection from the light source input side of the optical interference cavity (such as the left side with arrows in Figure 2 ) is a reflection spectrum, and the inverse spectrum of the reflection spectrum can be obtained, and the inverse spectrum is Figure 3 The comb-shaped spectrum shown with a certain peak-to-peak distance is further analyzed for the inverse spectrum.

[0147] It should be noted that the laser emitting the laser signal can be a wavelength scanning laser, and the laser can have a fixed scanning bandwidth. For example, a laser with a bandwidth of 40nm, the output wavelength continuously scans in the range of 1520nm to 1560nm, and the peak signal in the comb-shaped spectrum that meets the range of 1520nm to 1560nm is scanned.

[0148] Wherein, the bandwidth of the laser can also be referred to as optical bandwidth, scanning bandwidth or working bandwidth, and the width of the bandwidth can be determined according to the full width at half maximum (FWHM).

[0149] From the above, it can be calculated that the bandwidth of the laser is 1560nm-1520nm=40nm, and the center point wavelength value of the bandwidth of the laser is (1520nm+1560nm) / 2=1540nm.

[0150] It should be noted that in the application scenario of the pantograph, the collected sensor signals often have the characteristics of changing extremely fast, such as the values of parameters such as pantograph-catenary impact and contact force are constantly changing. For the case of fast-changing variable parameters, the code string problem is particularly serious, resulting in reduced accuracy of analysis results.

[0151] In the embodiment of the present application, in order to reduce the code string, only a single peak in the spectrum output from the optical interference cavity is located within the bandwidth of the laser, such as Figure 3 The scanning bandwidth shown is only a single peak. Further, in order to achieve only a single peak in the spectrum output from the optical interference cavity within the bandwidth of the laser, the cavity length of the optical interference cavity can be limited after the scanning bandwidth has been determined.

[0152] Specifically, the following steps can be used to calculate the cavity length of the optical interference cavity in the embodiment of the present application.

[0153] First, according to the fact that only a single peak in the spectrum output from the optical interference cavity is located within the bandwidth of the laser, the following formula is used to calculate different k mid Corresponding l FP .

[0154]

[0155]

[0156]

[0157] Wherein, l FP is used to represent the cavity length of the optical interference cavity, k mid is used to represent the preset longitudinal mode number of the fiber sensor, k mid is a positive integer, and k mid ≥2, W laser is used to represent the bandwidth of the laser that emits the laser signal, λ ctr is used to represent the center wavelength value of the bandwidth of the laser.

[0158] λ FP is used to represent the wavelength value of the peak within the bandwidth of the laser, that is, the wavelength value at which the comb-shaped spectrum output by the fiber sensor has the maximum intensity within the bandwidth of the laser. It can be understood that, since there is only a single peak in the comb-shaped spectrum output by the fiber sensor in the present application and located within the bandwidth of the laser, there is only a single wavelength value at which the intensity is maximum.

[0159] Secondly, according to the fact that the adjacent peaks cannot be located within the bandwidth of the laser, the following formula is used to exclude unsuitable k midand its corresponding l FP .

[0160]

[0161]

[0162] Again k st = k mid + 1, k ed = k mid - 1, substituting into the above formula, we have:

[0163]

[0164] Let Δλ ed-st ≥ 2W laser

[0165] We can get

[0166] Where, λ st , λ ed respectively represent the wavelength value corresponding to the adjacent wave peak, k st , k ed respectively represent the longitudinal mode number of the adjacent wave peak.

[0167] It should be pointed out that after the cavity length is calculated and the optical fiber sensor is made by using the preset longitudinal mode number (such as k mid = 20) and the preset bandwidth of the laser, the wave peak obtained by scanning the optical fiber sensor with the laser within the bandwidth W laser must be the comb wave peak of the longitudinal mode number k mid = 20, at this time according to k st = k mid + 1, k ed = k mid - 1, we can know that k st = 21, k ed = 20.

[0168] In the embodiment of the present application, according to the bandwidth of the laser device emitting the laser signal, the center wavelength value of the bandwidth of the laser device, and the preset longitudinal mode number of the optical fiber sensor, the cavity length of the optical interference cavity can be determined by using a formula, so that only a single peak exists in the comb-shaped spectrum output from the optical interference cavity within the bandwidth of the laser device, thereby avoiding the signal interference of adjacent peaks on the peak in the analysis process, and effectively preventing code stringing. Further, based on the above cavity length limitation, a small-size and small-volume optical fiber sensor can be formed, thereby facilitating the manufactured sensor chip to realize compact structure and lighter quality on the basis of maintaining good parameter consistency, high sensitivity, large dynamic range, good linearity, stable performance, strong reliability, and the like. Compared with the electronic sensor in the prior art, since the volume is large and the quality is heavy, the electronic sensor cannot be installed on the electric passenger car, but can only be installed on the detection vehicle, the engineering vehicle, or the freight locomotive. By using the technical solution in the embodiment of the present application, the monitoring system of the pantograph can not only avoid affecting the normal operation of the pantograph, but also can realize multi-directional monitoring, and accurately collect, analyze, and feed back the operation parameters related to the pantograph, the contact line, and the pantograph-catenary relationship in real time.

[0169] It should be noted that the cavity length of the optical interference cavity obtained by using the above content is as follows: Figure 3 The peak shown can be located at any position within the bandwidth of the laser device. When the peak is located at the edge position of the bandwidth of the laser device, the adjacent peaks before and after the peak can enter the bandwidth of the laser device due to manufacturing errors and the like, thereby causing code stringing.

[0170] Further, the cavity length of the optical interference cavity can satisfy the following formula:

[0171]

[0172] wherein, l ctr is used to represent the cavity length of the optical interference cavity.

[0173] It should be noted that l FP and l ctr are both used to represent the cavity length of the optical interference cavity, and the cavity length l FP can be selected from a plurality of values satisfying the condition, and the cavity length l ctr can be a further cavity length preferred value.

[0174] Specifically, the cavity length of the optical interference cavity in the embodiment of the present application can be calculated by using the following steps, so that the peak can be located at the center position within the bandwidth of the laser device, that is, λ FP = λ ctr .

[0175] Let λ FP = λ ctr ,

[0176]

[0177]

[0178] Again k st = k mid + 1, k ed = k mid - 1, into the above formula, we get:

[0179]

[0180] Let Δλ ed-st ≥ 2W laser

[0181]

[0182] In the embodiment of the present application, by setting the cavity length of the optical interference cavity to satisfy the above formula, it can be ensured that in the comb-shaped spectrum output from the optical interference cavity, not only a single wave peak is located within the bandwidth of the laser, but also the wave peak is located at the center position of the bandwidth of the laser, so that in the analysis process, it is easier to avoid the signal interference of adjacent wave peaks on the wave peak, further effectively prevent code string, and further, when the wave peak is located at the center position of the bandwidth of the laser, full-bandwidth measurement of the laser can be realized, and the measurement effect is improved.

[0183] In a specific implementation, taking the optical bandwidth of 40nm between the wavelength of 1520nm to 1560nm of the laser bandwidth and the designed center wavelength of 1540nm as an example, at this time, the longitudinal mode number k mid ∈ [2, 3, 4, … 38], that is, there are 37 cavity lengths satisfying the above condition.

[0184] Further, the fiber sensor can be selected from: a Micro-Electro-Mechanical System (MEMS) fiber sensor, a Micro-Opto-Electro-Mechanical System (MOEMS) fiber sensor, and a Micro-Opto-Mechanical System (MOMS) fiber sensor.

[0185] Taking the MEMS fiber sensor as an example, the MEMS fiber sensor technology is a 21st century frontier technology based on micron / nanometer mechanics and optics. The mass, elastic support, optical reflection mirror, and light incidence and emission waveguide system of the technology are directly integrated on a micro chip, and the all-optical detection and transmission of vibration, pressure, current, temperature and other signals are truly realized. The manufactured MEMS chip has the advantages of compact structure, integrated packaging, good parameter consistency, high sensitivity, large dynamic range, good linearity, stable performance, reliability and the like.

[0186] The silicon-based sensitive structure of the MEMS chip is integrated and manufactured by using micro-electro-mechanical technology, and the signal is detected and read by using fiber detection technology, so that the MEMS sensor technology and the fiber sensor technology have the common advantages. The MEMS fiber sensor technology overcomes the mutual restriction of "wide frequency" and "high precision" of the existing sensor technology, and has the characteristics of passivity, wide temperature, miniaturization, anti-electromagnetic interference, lightness, easy networking and maintenance-free, so that long-term accurate measurement can be realized, and the complexity and cost of intelligent operation and maintenance system are reduced. Therefore, the MEMS fiber sensor technology is very suitable for real-time monitoring of the pantograph, the contact wire and the relationship therebetween.

[0187] It should be pointed out that the MOEMS fiber sensor and the MOMS fiber sensor in the embodiment of the present application can have the advantages of the MEMS fiber sensor.

[0188] It should be pointed out that in the embodiment of the present application, the monitoring system can further include a fiber grating sensor and other appropriate sensors, which can provide a strong supplement to the above-mentioned fiber sensor containing an optical interference cavity.

[0189] For example, the fiber grating sensor can be a Fiber Bragg Grating (FBG) sensor, for example, a chirped FBG fiber grating sensor.

[0190] Further, the fiber sensor can be a passive sensor.

[0191] In the embodiment of the present application, by using a passive sensor, passive detection without electricity at the detection end can be realized, the anti-electromagnetic capability can be effectively improved, the danger to passengers caused by power supply can be avoided, electrical accidents can be avoided, the interference caused by detection can be avoided, the normal monitoring can be ensured, and the detection accuracy can be improved.

[0192] Further, according to the type of the signal to be collected, the fiber sensor can include multiple types of sensors.

[0193] Reference Figure 4 , Figure 4Fig. 1 is a schematic diagram of the installation position of an optical fiber sensor in a monitoring system on a pantograph according to an embodiment of the present application.

[0194] Figure 4 The pantograph shown can include a chassis 31, a four-bar linkage structure, and a pantograph head 34, and can also include a pneumatic control box 35.

[0195] The pantograph head 34 can include a carbon slide plate 341 and a pantograph head support 342.

[0196] In Figure 4 The pantograph shown can include two carbon slide plates 341 and four pantograph head supports 342 for each pantograph head 34, and each pair of pantograph head supports 342 can be arranged on both sides of a single carbon slide plate 341. It should be noted that the pantograph head can also include other numbers of carbon slide plates and pantograph head supports, and the present embodiment does not limit the number and positional relationship of the carbon slide plates and pantograph head supports.

[0197] Figure 4 The pantograph shown can include two carbon slide plates 341 and four pantograph head supports 342 for each pantograph head 34, and each pair of pantograph head supports 342 can be arranged on both sides of a single carbon slide plate 341. It should be noted that the pantograph head can also include other numbers of carbon slide plates and pantograph head supports, and the present embodiment does not limit the number and positional relationship of the carbon slide plates and pantograph head supports.

[0198] Further, the optical fiber sensor can include at least one contact force sensor to collect pressure signals, the pantograph can include one or more pantograph heads 34, and each pantograph head 34 can include a pantograph head support 342; for the pantograph head 34 installed with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support 342.

[0199] In the present embodiment, for the pantograph head 34 installed with the contact force sensor, by arranging at least one contact force sensor inside or on the surface of the pantograph head support 342, it is possible to monitor the contact line hard point, the pull-out value, the pantograph-catenary contact force, the impact, and the arcing.

[0200] Further, the contact force sensors can be arranged in pairs, and the contact force sensors in each pair are installed on the two ends of the same bow head 34.

[0201] In the embodiment of the present application, the contact force sensors are arranged in pairs, and the contact force sensors in each pair are installed on the two ends of the same bow head 34, so as to monitor the contact force between the pantograph and the contact wire, the abrasion amount, the abrasion area and the eccentric abrasion of the carbon slide plate 341 of the pantograph.

[0202] In the embodiment of the present application, the contact force sensors are arranged in pairs, and the contact force sensors in each pair are installed on the two ends of the same bow head 34, so as to monitor the contact force between the pantograph and the contact wire, the abrasion amount, the abrasion area and the eccentric abrasion of the carbon slide plate 341 of the pantograph.

[0203] In a specific embodiment of the present application, the pressure signal can be used to indicate the mass of the carbon slide plate structure of the pantograph, wherein the carbon slide plate structure can include the carbon slide plate (and its base) and the two horns.

[0204] In combination with the above Figure 4 and Figure 5 , Figure 5 is a schematic diagram of the abrasion amount of the carbon slide plate changing with time in the embodiment of the present application.

[0205] Specifically, the processor can use the following formula to determine the abrasion amount of the carbon slide plate structure:

[0206]

[0207]

[0208] ΔG 0,i (t)=G' 0,i (t)-G 0,i

[0209] wherein G0,i G' for representing the initial mass of the i-th carbon slide structure when it is not worn 0,i (t) for representing the mass of the i-th carbon slide structure at time t, K G,i,j for representing the contact force coefficient of the j-th contact force sensor of the i-th carbon slide structure, λ D,i,j for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure when it is not subjected to any force, λ CS,i,j for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure when the i-th carbon slide structure is not worn, λ' CS,i,j for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure at time t, N S for representing the number of contact force sensors on the same carbon slide, i for representing the serial number of the carbon slide structure, and j for representing the serial number of the contact force sensor of each carbon slide structure.

[0210] In one specific embodiment of the present application, the N S may also be used to represent the number of arch supports at both ends of the carbon slide structure, which can be set to 2.

[0211] It can be understood that the initial mass of the carbon slide structure can be measured when it is not worn, such as when it is to be installed or newly installed, to obtain G 0,i .

[0212] Regarding the eccentric wear of the carbon slide plate 341, when the vehicle is running, since the contact wire is in a "Z" shape on the running track, two contact force sensors on each carbon slide plate 341 can respectively sense the pressure from the contact wire, which periodically changes with the change of the pull-out value of the contact wire, so that the trajectory of the contact point between the contact wire and the carbon slide plate 341 of the pantograph is in a "Z" shape within the main wear area of the carbon slide plate 341 with a length L. In the normal working condition, the wear area of the carbon slide plate 341 is within the length L of the carbon slide plate 341 and is symmetrically distributed about the center line of the carbon slide plate 341, which is called the main wear area. When the pull-out value of the contact wire on the track exceeds the deviation range, or / and the pantograph head is laterally unstable, the trajectory of the contact point between the contact wire and the carbon slide plate 341 will exceed the main wear area on one side of the center line of the carbon slide plate 341, causing the wear amount on one side of the carbon slide plate 341 (bounded by the center line of the carbon slide plate 341) to be greater than that on the other side, and even causing the phenomenon of horn wear. In addition, in the state of falling pantograph or in the state of natural lifting pantograph without pressure from the contact wire on the pantograph, the measurement value sensed by the contact force sensor integrated on the pantograph head support at each end of each carbon slide plate 341 is about half of the total mass of the carbon slide plate 341. If the measurement value of the contact force sensor at one end of the same carbon slide plate 341 is much greater than that of the contact force sensor at the other end, there is a possibility of eccentric wear of the carbon slide plate 341.

[0213] Further, the pantograph head supports 342 can correspond to the contact force sensors one by one, and each pantograph head support is internally or externally provided with a corresponding contact force sensor.

[0214] In the embodiment of the present application, the pantograph head supports 342 correspond to the contact force sensors one by one, and each pantograph head support 342 is internally or externally provided with a corresponding contact force sensor, so that all the pantograph heads can be monitored to avoid hidden dangers due to missed detection.

[0215] Further, the contact force sensors can be internally embedded with temperature sensors, or the contact force sensors can be coupled with temperature sensors.

[0216] In the embodiment of the present application, by providing the temperature sensors, temperature compensation and sensing real-time temperature can be realized.

[0217] Combined with reference to Figure 4 , Figure 6 and Figure 7 , Figure 6 is a time-domain schematic diagram of the contact force between the pantograph head and the pantograph net in the embodiment of the present application when the pantograph is running, Figure 7 is a time-domain schematic diagram of the contact force between the pantograph head and the pantograph net sensed by the contact force sensors at both ends of the same carbon slide plate in the embodiment of the present application when the pantograph is running.

[0218] It should be noted that, Figure 6 The pantograph head shown in the figure is the force perceived by the pantograph head when the train is running. The force is the force perceived by the pantograph head as a whole. Figure 7 The forces perceived by the two end contact force sensors on the same carbon slide rail are the forces perceived by the contact force sensors themselves when the train is running.

[0219] For the contact force between the pantograph and the catenary, when the train is running, in order to enable the pantograph to normally draw current from the contact wire, a certain contact force must be maintained between the pantograph and the catenary. The size of the contact force depends on the structure of the pantograph. Generally, the contact force between the pantograph and the catenary is a certain value, for example, 80 N or 120 N.

[0220] In the specific implementation, each set of carbon slide rails 341, carbon slide rail bases, and horns are supported by two pantograph head supports 342, and the contact force sensors are integrated on the damping / buffer system of the pantograph head supports 342. The damping / buffer system of different types of pantograph heads is different, such as spring box type, plate spring type, and tension spring type. The contact force sensor simultaneously embeds a temperature sensor inside as a temperature compensation or / and to perceive the instantaneous temperature during arcing.

[0221] First, when the contact wire and the pantograph head 34 are not in contact, the contact force sensor only perceives the gravity of the components such as the carbon slide rails 341, carbon slide rail supports, and horns supported by the pantograph head 34; then, the measured value of the contact force sensor when not in contact with the contact wire is zeroed for the contact force between the pantograph and the catenary; finally, when the contact wire is in contact with the pantograph head 34 and a certain force is generated, the sum of the measured values of each contact force sensor is the contact force between the pantograph and the catenary. Moreover, since the contact point between the contact wire and the carbon slide rail 341, i.e., the pull-out value of the contact wire, is a "Z" shape change, the measured values of the contact force sensors at both ends of the same carbon slide rail 341 are also a "Z" shape change. When the train is stopped, the measured value of each contact force sensor on a single carbon slide rail 341 is not changed, and the time domain curve is flat; when the train is running, the measured value of each contact force sensor on a single carbon slide rail 341 is changed, and the time domain curve is sawtooth-shaped. However, the contact force borne by a single carbon slide rail 341 is the sum of the measured values of the contact force sensors at both ends, and the contact force between the pantograph and the catenary is the sum of the contact forces borne by all carbon slide rails 341.

[0222] It should be noted that the contact force between the pantograph head and the contact line also fluctuates within a certain range during the operation of the vehicle, such as 120N±5N, and the contact force is considered abnormal if it exceeds the fluctuation range. If the contact force is lower than the normal contact force working range, the pressure between the pantograph head and the contact line is too small, and frequent arcing will occur, which will cause excessive electrical wear of the carbon slide plate 341. If the contact force is higher than the contact force working range, the pressure between the pantograph head and the contact line is too large, and the impact vibration between the pantograph head and the contact line is abnormal, which will cause excessive mechanical wear of the carbon slide plate 341.

[0223] In a specific embodiment of the embodiment of the application, the pressure signal is used to indicate the contact force between the pantograph head and the contact line; and the processor can determine the contact force between the pantograph head and the contact line by using the following formula:

[0224] F S,i,j (t)=K S,i,j [λ i,j (t)-λ 0,i,j +k T,i,j (T(t)-T0)]

[0225]

[0226] Wherein, F S,i,j (t) is used to represent the contact force value between the contact force sensor on the jth pantograph head support of the ith group of carbon slide plates of the pantograph head and the contact line at time t, K S,i,j is used to represent the contact force coefficient of the jth contact force sensor of the ith group of carbon slide plates, λ i,j (t) is used to represent the wavelength value of the jth contact force sensor of the ith group of carbon slide plates at time t, λ 0,i,j is used to represent the wavelength value of the jth contact force sensor of the ith group of carbon slide plates when the pantograph head has no mutual force with the contact line, k T,i,j is used to represent the temperature drift coefficient of the jth contact force sensor of the ith group of carbon slide plates, T(t) is used to represent the temperature value at time t, T0 is used to represent the temperature value at the initial time, F cp (t) is used to represent the contact force value between the pantograph head and the contact line at time t, N C is used to represent the number of carbon slide plates on the pantograph head, N S is used to represent the number of pantograph head supports on the same group of carbon slide plates.

[0227] Continuing to refer to Figure 4Further, the optical fiber sensor can comprise at least one acceleration sensor for collecting acceleration signals, the pantograph can comprise one or more pantograph heads 34, each pantograph head 34 can comprise a carbon slide 341, a pantograph head support 342 connected to two ends of the carbon slide 341 respectively, and a connecting component for connecting the carbon slide 341 and the pantograph head support 342; for the pantograph head 34 provided with the acceleration sensor, the acceleration sensor can be installed at one or more of the following positions: the inside or surface of the pantograph head support 342, and the connecting component.

[0228] In the embodiment of the present application, for the pantograph head 34 provided with the acceleration sensor, the acceleration sensor can be installed at one or more of the following positions: the inside or surface of the pantograph head support 342, and the connecting component, so as to monitor the hard point of the contact wire, the impact, the height value of the guide, and effectively distinguish the flexible net and the rigid net.

[0229] Further, the acceleration sensor can be provided in pairs; wherein the acceleration sensors in pairs can be respectively installed on the pantograph head supports 342 at two ends of the same pantograph head 34, or the acceleration sensors in pairs can be respectively installed on the connecting components at two ends of the same pantograph head 34.

[0230] In the embodiment of the present application, the acceleration sensors are provided in pairs, wherein the acceleration sensors in pairs can be respectively installed on the pantograph head supports 342 at two ends of the same pantograph head 34, or the acceleration sensors in pairs can be respectively installed on the connecting components at two ends of the same pantograph head 34, so as to effectively monitor the stability of the pantograph head 34 by using the acceleration signals at two ends of the same pantograph head 34.

[0231] In the specific implementation, the dynamic stability of the pantograph head 34 can be monitored in real time by respectively performing second-order integration on the transverse acceleration value and the longitudinal acceleration value of the three-way acceleration sensor integrated on both sides of the single carbon slide 341. If the dynamic transverse offset value generated by the vibration of the pantograph head 34 exceeds the deviation value specified by the center line of the vehicle operation line, there is a condition of transverse instability of the pantograph head 34; if the dynamic vertical amplitude value generated by the vibration of the pantograph head 34 perceived by the acceleration sensor on one side of the single carbon slide 341 is much larger than the vertical amplitude value perceived by the acceleration sensor on the other side of the same carbon slide, there is a condition of vertical instability of the pantograph head 34 caused by fatigue of the buffer or / and damping system of the pantograph head 34. In addition, the stability of the pantograph head can also be evaluated by the dynamic trajectory of the contact wire at the contact point of the carbon slide 341, or / and by comparing the measurement values of the contact force sensors on both sides of the single carbon slide 341 in the state of the pantograph falling or in the state of the pantograph naturally rising without pressure applied to the pantograph by the contact wire.

[0232] During train operation, the vibration trajectories of the two ends of the carbon slide of the pantograph head can be drawn in the "vertical-horizontal" plane by the displacement values at each time, and the dynamic stability of the pantograph head can be judged by comparing the vibration amplitudes of the two ends of the same set of carbon slides. In the free and static state of the pantograph head, the static stability of the pantograph head can be judged by comparing the values of the contact force sensors on the head supports of the two ends of the same set of carbon slides.

[0233] The pantograph head state generally includes four states: a falling pantograph state, a pantograph head not in contact with a contact wire in a rising pantograph state, a state in which the pantograph head is in contact with the contact wire and generates mutual interaction force in the rising pantograph state, and a motion state in which the pantograph head is in contact with the contact wire and generates mutual interaction force in the rising pantograph state. The free and static state can be used to indicate the falling pantograph state and the state in which the pantograph head is not in contact with the contact wire in the rising pantograph state.

[0234] Specifically, the acceleration signal can be used to indicate the acceleration of at least one pantograph head in the lateral direction and the acceleration of at least one pantograph head in the vertical direction; and the processor can determine the vertical and lateral vibration displacements of the pantograph head by using the following formula:

[0235]

[0236]

[0237] wherein d H (t) is used to represent the displacement value of the pantograph head in the lateral direction at time t, d 0,H is used to represent the initial displacement value of the pantograph head in the lateral direction, v 0,H is used to represent the initial velocity value of the pantograph head in the lateral direction, a H (t) is used to represent the acceleration value of the pantograph head in the lateral direction at time t, d V (t) is used to represent the displacement value of the pantograph head in the vertical direction at time t, d 0,V is used to represent the initial displacement value of the pantograph head in the vertical direction, v 0,V is used to represent the initial velocity value of the pantograph head in the vertical direction, a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t.

[0238] Furthermore, the head supports 342 and the acceleration sensors can correspond one by one, and each head support 342 has a corresponding acceleration sensor installed inside or on the surface.

[0239] In the embodiment of the present application, the bow head supports 342 correspond to the acceleration sensors one by one, and each of the bow head supports 342 is internally or externally provided with a corresponding acceleration sensor, so that all the bow heads can be monitored, and hidden dangers due to missed detection can be avoided.

[0240] Further, the acceleration sensor can be an acceleration sensor integrating multiple direction measurement functions, and the acceleration sensor can further include multiple sub-sensors, and each of the sub-sensors is used for measuring an acceleration signal in a single direction.

[0241] Further, the acceleration sensor can be a fiber-optic three-axis acceleration sensor, so as to accurately and conveniently collect three-axis acceleration signals, wherein the three-axis acceleration signals can include acceleration signals in a horizontal direction, a vertical direction and a longitudinal direction, and any two of the three directions are orthogonal.

[0242] Further, the acceleration sensor can be internally embedded with a current sensor, or the acceleration sensor can be coupled with a current sensor.

[0243] In the embodiment of the present application, the current sensor can be provided, so as to realize the functions of real-time current measurement and the like.

[0244] In one specific embodiment of the embodiment of the present application, a contact force sensor and an acceleration sensor can be used to determine the contact line hard point.

[0245] With reference to Figure 4 , Figure 6 and Figure 8 , Figure 8 is a time-domain schematic diagram of a vertical acceleration value of the acceleration sensor located at the bow head during driving.

[0246] For the contact line hard point, the vertical acceleration value or / and the longitudinal acceleration value of the acceleration sensor integrated on the bow head 34 of the pantograph can be used to monitor the hard point on the contact line in real time. Generally, when the vehicle (such as an electric passenger car) is running, the bow head 34 of the pantograph will vibrate up and down in the vertical direction, and according to the driving speed, and the height and type of the contact line, the bow head 34 of the pantograph will vibrate within a certain range, for example, ±2g. With reference to Figure 8 If the bow head 34 of the pantograph hits the hard point on the contact line, an impact of ±100-200g will be generated instantaneously, and in combination with the train information management system, the position of the contact line hard point can be located, so as to facilitate the maintenance of the contact line.

[0247] In addition, the hard point of the contact line can also be monitored by the contact force sensor on the pantograph head 34. When the pantograph head 34 hits the hard point on the contact line, the head 34 impacted by the hard point will be instantaneously separated from the contact line. At this time, there is no force transmission between the pantograph and the catenary due to the mutual separation, and thus the value detected by the contact force sensor is 0 or even a negative value slightly lower than 0. Then, the head 34 and the contact line will rebound in opposite directions and collide again. Referring to Figure 6 At this time, the value of the contact force between the pantograph and the catenary monitored by the contact force sensor will be abnormally large, which can also be regarded as a basis for judging the hard point of the contact line.

[0248] Specifically, the optical fiber sensor can further include at least one contact force sensor for collecting a pressure signal. The pantograph includes one or more heads 34, and each head 34 includes a head support 342. For the head 34 provided with the contact force sensor, the contact force sensor is installed inside or on the surface of the head support 342. The pressure signal is used to indicate the contact force between the head 34 and the contact line. The acceleration signal is used to indicate the acceleration of at least one head 34 in the lateral direction and the acceleration of at least one head 34 in the vertical direction. The processor can determine the acceleration value of the head 34 in the vertical direction and the contact force between the head 34 and the contact line by using the following formula:

[0249] a V (t) = K V [λ V (t) - λ 0,V +k T,V (T(t) - T0)]

[0250] F S (t) = K S [λ S (t) - λ 0,S +k T,S (T(t) - T0)]

[0251] wherein a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t, K V is used to represent the acceleration coefficient of the acceleration sensor in the vertical direction, λ V (t) is used to represent the wavelength value of the acceleration sensor in the vertical direction at time t, λ 0,V is used to represent the wavelength value of the acceleration sensor in the vertical direction in the static state, k T,V is used to represent the temperature drift coefficient of the acceleration sensor in the vertical direction, F S (t) is used to represent the contact force value between the contact force sensor and the contact line at time t, K Sλ is used to represent the contact force coefficient of the contact force sensor S (t) is used to represent the wavelength value of the contact force sensor at time t, λ0, S k is used to represent the wavelength value of the contact force sensor when the pantograph head has no interaction with the contact wire T,S T is used to represent the temperature drift coefficient of the contact force sensor, T(t) is used to represent the temperature value T at time t, and T0 is used to represent the temperature value at the initial time.

[0252] For the definition of the pantograph-wire contact force and more, please refer to the foregoing description, which will not be repeated here.

[0253] Referring to Figure 9 , Figure 9 is a time-domain variation diagram of the contact wire pull-out value of the carbon slide plate during driving in an embodiment of the present application.

[0254] For the contact wire pull-out value, assuming that the longitudinal center line of the pantograph coincides with the center line of the track line, the dynamic pull-out value of the contact wire during the driving of the vehicle can be obtained by calculating the pantograph-wire contact force value measured by the contact force sensors at both ends of the single carbon slide plate 341 of the pantograph, and combining the running speed of the vehicle (the running speed of the train can be obtained by integrating the longitudinal acceleration value detected by the acceleration sensor on the head, or can be obtained by the train information management system).

[0255] Specifically, the optical fiber sensor further comprises at least one contact force sensor for collecting a pressure signal, the pantograph comprises one or more pantograph heads 34, each pantograph head 34 comprises a pantograph head support 342; for the pantograph head provided with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support 342; the pressure signal is used to indicate the pantograph-wire contact force between the pantograph head 34 and the contact wire; the acceleration signal is used to indicate the acceleration of at least one pantograph head 34 in the longitudinal direction; the processor can determine the pull-out value of the contact wire by using the following formula:

[0256]

[0257] or,

[0258]

[0259]

[0260]

[0261] wherein Z C (t) is used to represent the pull-out value of the contact wire at time t, Z Cis negative, Z C is positive, L S is the distance between the centers of the two head supports with buffer or / and damping system at both ends of the same group of carbon slides, F S,i,drg and F S,i,gch respectively represent the contact force values between the contact force sensors on the right and left head supports of the i-th group of carbon slides of the pantograph head and the contact wire at t, v L (t) represents the speed value of the pantograph head in the longitudinal direction at t, v 0,L represents the initial speed value of the pantograph head in the longitudinal direction, a L (t) represents the acceleration value of the pantograph head in the longitudinal direction at t, a L , D L (t) represents the running distance of the train at t, D 0,L represents the initial running distance of the train.

[0262] It should be noted that, Figure 9 L shown in the figure is the length of the carbon slide, and from -L / 2 to +L / 2 represents the overall length of the carbon slide.

[0263] Referring to Figure 10 , Figure 10 is a time-domain schematic diagram of the contact wire height value when driving in an embodiment of the present application.

[0264] For the contact wire height value, by twice integrating the vertical acceleration value in the acceleration sensor integrated on the pantograph head 34, and combining the pantograph height when the pantograph is working and the height of the roof relative to the ground, the dynamic height value of the contact wire can be monitored in real time.

[0265] Regarding the effective distinction between flexible and rigid nets, the flexible contact wire or the rigid contact wire can be distinguished by calculating the contact wire height value and the measured vertical acceleration value of the acceleration sensor. Generally, flexible contact wires are mostly outside tunnels, while rigid contact wires are mostly inside tunnels, and the height value of the flexible contact wire is greater than that of the rigid contact wire. In addition, the amplitude of the vibration of the pantograph head 34 caused by the flexible contact wire is slightly greater than that of the pantograph head 34 caused by the rigid contact wire.

[0266] Specifically, the acceleration signal is used to indicate the acceleration of at least one head in the vertical direction; the processor can determine the height value of the contact wire by using the following formula:

[0267]

[0268]

[0269] wherein, v V (t) is used to represent the vertical direction speed value of the pantograph head at time t, v 0,V is used to represent the initial vertical direction speed value of the pantograph head, a V (t) is used to represent the vertical direction acceleration value of the pantograph head at time t, h C (t) is used to represent the contact line height value at time t, h Tr is used to represent the height of the roof of the car in which the pantograph is located relative to the ground level, h cp,0 (P A,0 ) is used to represent the height of the upper surface of the pantograph head carbon slide relative to the roof when the air bag / cylinder pressure value is P A,0 A,0 is used to represent the air bag / cylinder pressure value in the static lifting state of the pantograph when the required pantograph-catenary contact force is in the normal current collection state.

[0270] It should be noted that the air bag / cylinder pressure value can be obtained in a conventional manner, and can also be measured by an optical fiber sensor. Hereinafter, the case in which the optical fiber sensor includes at least one air pressure sensor to collect an air pressure signal will be described.

[0271] For pantograph-catenary impact, also known as contact line impact, the suspension geometry parameter of the contact line is out of tolerance, or / and the pantograph head 34 is unstable and the lifting height is out of tolerance, which will cause the pantograph-catenary impact. Therefore, the abnormal vibration of the pantograph head 34 can be perceived by the vertical acceleration value or / and the longitudinal acceleration value of the acceleration sensor integrated on the pantograph head 34, so as to determine the pantograph-catenary impact and locate the section.

[0272] For pantograph-catenary arcing, the contact between the contact line and the pantograph head 34 is unstable during the operation of the vehicle, which causes the contact line and the pantograph head 34 to be separated from each other, so that the air gap is broken down to cause a discharge phenomenon, accompanied by the generation of instantaneous high temperature and high frequency electromagnetic pulse phenomenon. Therefore, arcing is a state of mechanical separation but electrical connection.

[0273] In specific implementation, the pantograph-catenary impact can be perceived by the vertical acceleration value or / and the longitudinal acceleration value of the acceleration sensor on the pantograph head 34, and the greater the pantograph-catenary impact, the higher the frequency of arcing.

[0274] It should be noted that in specific implementation, the real-time temperature value, the current value and the air pressure value monitored by the optical fiber current sensor integrated in the acceleration sensor shell, the optical fiber temperature sensor integrated in the contact force sensor shell, and the optical fiber air pressure sensor integrated in the air path of the pneumatic control box can be used to comprehensively determine the generation of pantograph-catenary arcing. ​

[0275] Further, the optical fiber sensor can include at least one temperature sensor to collect a temperature signal, the pantograph can include one or more pantograph heads 34, each pantograph head 34 can include a carbon slide plate 341, a pantograph head support 342 connected to both ends of the carbon slide plate 341 respectively, and a connecting component for connecting the carbon slide plate 341 and the respective pantograph head support 342; for the pantograph head 34 installed with the temperature sensor, the temperature sensor can be installed at one or more of the following: the inside or surface of the pantograph head support 342, the connecting component.

[0276] In the embodiment of the present application, for the pantograph head installed with the temperature sensor, the temperature sensor is installed at one or more of the following: the inside or surface of the pantograph head support 342, the connecting component, which has the opportunity to monitor the arc between the pantograph and the catenary according to the temperature signal.

[0277] It can be understood that when the arc between the pantograph and the catenary occurs, the temperature nearby will increase significantly, and using the temperature sensor to monitor the temperature and determine whether the arc occurs when the temperature exceeds the preset temperature threshold value, which helps to realize accurate monitoring of the arc between the pantograph and the catenary.

[0278] Further, the optical fiber sensor can include at least one current sensor to collect a current signal, the pantograph can include one or more pantograph heads 34, each pantograph head 34 can include a carbon slide plate 341, a pantograph head support 342 connected to both ends of the carbon slide plate 341 respectively, and a connecting component for connecting the carbon slide plate 341 and the respective pantograph head support 342; for the pantograph head 34 installed with the current sensor, the current sensor can be installed at one or more of the following: the inside or surface of the pantograph head support 342, the connecting component.

[0279] In the embodiment of the present application, for the pantograph head installed with the current sensor, the current sensor is installed at one or more of the following: the inside or surface of the pantograph head support 342, the connecting component, which has the opportunity to monitor the arc between the pantograph and the catenary according to the current signal.

[0280] It can be understood that when the arc between the pantograph and the catenary occurs, the current on the line will be significantly abnormal, and using the current sensor to monitor the current and determining whether the arc occurs when the current exceeds the preset current threshold value, which helps to realize accurate monitoring of the arc between the pantograph and the catenary.

[0281] Further, the optical fiber sensor can include at least one load sensor to collect a load signal, the pantograph can include a four-bar linkage structure; the load sensor can be installed at one or more of the following: the upper arm 323 of the four-bar linkage structure, the lower arm 322 of the four-bar linkage structure, the lower guide rod 321 of the four-bar linkage structure.

[0282] In the embodiment of the present application, the load sensor is installed at one or more of the following positions of the four-bar linkage structure: the upper arm 323, the lower arm 322, and the lower guide rod 321, so as to monitor the tension and bending moment of the upper arm 323, the lower arm 322, and the lower guide rod 321. Further, the load sensor arranged at the lower guide rod 321 can also be used to monitor the jamming of the connecting shafts at both ends of the lower guide rod 321, so as to determine the jamming condition of the hinge system.

[0283] Furthermore, the load sensor can be embedded with a temperature sensor, or the load sensor can be coupled with a temperature sensor.

[0284] In the embodiment of the present application, by arranging the temperature sensor, temperature compensation and real-time temperature sensing can be achieved.

[0285] With reference to Figure 4 , Figure 11 and Figure 12 , Figure 11 is a structural schematic diagram of a four-bar linkage structure in the embodiment of the present application, Figure 12 is a position schematic diagram of a load sensor on the same circumferential section of a lower guide rod in the embodiment of the present application.

[0286] The four-bar linkage structure can include a lower guide rod 321, a lower arm 322, and an upper arm 323, and can also include a first connecting shaft 331, a second connecting shaft 332, a third connecting shaft 333, and a fourth connecting shaft 334.

[0287] The connecting shafts can be hinge shafts, such as spherical hinge shafts.

[0288] The first connecting shaft 331 can be used to connect the lower arm 322 and the chassis 31, the second connecting shaft 332 can be used to connect the lower guide rod 321 and the chassis 31, the third connecting shaft 333 can be used to connect the lower guide rod 321 and the upper arm 323, and the fourth connecting shaft 334 can be used to connect the lower arm 322 and the upper arm 323.

[0289] In the four-bar linkage mechanism of the pantograph, the distance between each shaft is constant, and the internal angle and shape of the four-bar linkage mechanism depend on the working height of the pantograph.

[0290] For monitoring the tension of the lower guide rod 321, the lower guide rod load sensor can be composed of four fiber optic stress chips with temperature compensation function, and the sensing direction of the four fiber optic stress chips is integrated on the outer wall of the lower guide rod 321 near the second connecting shaft 332 along the length direction of the lower guide rod 321. More specifically, for example, the tension of the lower guide rod 321 can be determined based on the comparison results of the tension when there is a load and when there is no load on the lower guide rod 321. The measurement of the tension of the lower guide rod can be the sum of the changes in force of each of the four fiber optic stress chips when there is a load compared to when there is no load. It should be noted that, taking a non-restrictive pantograph as an example, the maximum tension value at both ends of the lower guide rod can be 10000N, and the tension value under normal operation can be 7000N to 8000N.

[0291] Specifically, such as Figure 12 As shown, the load sensors can be installed on the same circumference of any cross-section of the lower guide rod. Taking eight load sensors as an example, they are installed in pairs at opposite positions. For instance, load sensor n=1 is located at end 1, and its opposite is load sensor n=5, located at end 1-opp. Similarly, load sensor n=2 is located at end 2, and its opposite is load sensor n=6, located at end 2-opp; load sensor n=3 is located at end 3, and its opposite is load sensor n=7, located at end 3-opp; load sensor n=4 is located at end 4, and its opposite is load sensor n=8, located at end 4-opp.

[0292] Furthermore, the load signal can be used to indicate the tension of the lower guide rod; the processor can determine the tension value of the lower guide rod using the following formula:

[0293]

[0294] Among them, F pf (t) represents the tension value of the lower guide rod at time t, N represents the total number of load sensors on the same cross-section of the lower guide rod, and K represents the total number of load sensors on the same cross-section of the lower guide rod. pf,n λ is used to represent the tension coefficient of the nth fiber optic load sensor. n (t) represents the wavelength value of the nth load sensor at time t, λ 0,n k is used to represent the wavelength value of the nth fiber optic load sensor when there is no load. T,n The temperature drift coefficient of the nth fiber optic load sensor is used to represent the temperature value at time t, and T0 is used to represent the temperature value at the initial time.

[0295] For the bending moment monitoring of the lower guide rod 321, the structure of the load sensor for tension monitoring of the lower guide rod 321 can also be set, and then according to the comparison result of the bending moment when the load exists on the lower guide rod 321 and when the load does not exist, it can be determined whether the bending moment of the current lower guide rod 321 is within the normal bearing range.

[0296] Specifically, the load sensor can be installed in pairs on the same cross-sectional circumference of any cross section of the lower guide rod, and the pairs of load sensors can be centrally symmetric, and the load signal is used to indicate the bending moment of the lower guide rod; the processor can use the following formula to determine the bending moment value of the lower guide rod:

[0297] M i,i-opp (t) = K M,i {λ i (t) - λ 0,i +k T,i [T(t) - T0]} - K M-opp,i-opp {λ opp,i-opp (t) - λ 0-opp,i-opp +k T-opp,i-opp [T(t) - T0]}

[0298] Wherein, i = 1, 2, 3, …, I,

[0299] Wherein, M i,i-opp (t) is used to indicate the bending moment value of the lower guide rod in the i, i-opp bending direction at t, N is used to indicate the total number of load sensors on the same cross section of the lower guide rod, I is used to indicate the number of paired load sensors on the same cross section of the lower guide rod, K M,i is used to indicate the bending moment coefficient of the i-th load sensor of the lower guide rod, λ i (t) is used to indicate the wavelength value of the i-th fiber load sensor at t, λ 0,i is used to indicate the wavelength value of the i-th fiber load sensor when there is no load, k T,i is used to indicate the temperature drift coefficient of the i-th fiber load sensor, K M-opp,i-opp is used to indicate the bending moment coefficient of the fiber load sensor opposite to the i-th fiber load sensor of the lower guide rod, λ opp,i-opp (t) is used to indicate the wavelength value of the i-opp fiber load sensor opposite to the i-th fiber load sensor at t, λ 0-opp,i-opp is used to indicate the wavelength value of the i-opp fiber load sensor opposite to the i-th fiber load sensor when there is no load, k T-opp,i-opp is used to indicate the temperature drift coefficient of the i-opp fiber load sensor opposite to the i-th fiber load sensor, T(t) is used to indicate the temperature value at t, T0 is used to indicate the temperature value at the initial moment.

[0300] In a specific implementation, since the first connecting shaft 331, the second connecting shaft 332, the third connecting shaft 333 and the fourth connecting shaft 334 are all rotating, the inner angle of the four-bar linkage structure and its shape will change with the height change of the pantograph head 34. When the upper arm 323, the lower arm 322 and the lower guide rod 321 are under stress, a stuck state may occur, for example, causing the stressed part to bend and be difficult to restore.

[0301] Further, the optical fiber sensor can include at least one strain sensor to collect the deformation signal, and the pantograph can include a four-bar linkage structure and a chassis 31; the strain sensor can be installed at one or more of the following: the upper arm 323 of the four-bar linkage structure, the lower arm 322 of the four-bar linkage structure, the lower guide rod 321 of the four-bar linkage structure and the chassis 31.

[0302] In the embodiment of the present application, the strain sensor is installed at one or more of the following: the upper arm 323 of the four-bar linkage structure, the lower arm 322 of the four-bar linkage structure, the lower guide rod 321 of the four-bar linkage structure and the chassis 31, which has the opportunity to monitor the fatigue degree of the upper arm 323 of the four-bar linkage structure, the lower arm 322 of the four-bar linkage structure, the lower guide rod 321 of the four-bar linkage structure and the chassis 31 according to the deformation signal.

[0303] In a specific implementation, the optical fiber strain sensor can be arranged at the key stress position or / and the welding seam of the upper arm 323 and the lower arm 322 of the pantograph and the chassis 31 of the pantograph, which can be used for structural health monitoring of the pantograph frame, and can long-term monitor the fatigue degree of the upper arm 323, the lower arm 322 and the chassis 31 of the pantograph.

[0304] It should be noted that in general cases, the pantograph head height can work within a certain height range, for example, between 350mm and 2500mm. First, the lengths of L1, L2, L3 and L4, and the distance L5 from the load center of the lower guide rod load sensor to the shaft 332, and L6 between the shaft 332 and the shaft 334 can be measured. Second, the inner angles α1, α2, β, θ1 and θ2 of the four-bar linkage mechanism at different heights (such as every 50mm height) in the natural lifting state without pressure from the contact line on the pantograph head are measured, where α1 is the included angle between L4 and L6, α2 is the included angle between L2 and L6, β is the included angle between L1 and L4, θ1 is the included angle between L3 and L4, and θ2 is the included angle between L2 and L3.

[0305] Then, the maximum driving torque value of the pantograph lower arm, i.e. the maximum torque value of the rotation around the shaft 331, such as 1500 N*m or 2000 N*m, is combined with different types of pantographs, and the corresponding jammed pulling force value and the jammed bending moment value of the pantograph head at the lower conductor rail load sensor when the ball-type hinge shaft 332 or the shaft 333 at both ends of the lower conductor rail is completely jammed and cannot rotate under different heights are calculated respectively. Finally, the real-time measured pulling force value and the bending moment value of the lower conductor rail load sensor are combined and compared with the jammed pulling force value and the jammed bending moment value of itself in real time, so that whether the ball-type hinge shaft 332 and the shaft 333 at both ends of the lower conductor rail are jammed can be known in real time, and immediate warning can be achieved. In addition, by the positive and negative of the bending moment value at the lower conductor rail load sensor, the bending direction of the middle part of the lower conductor rail can be judged, and whether the shaft 332 is jammed or the shaft 333 is jammed can be distinguished, i.e. when the middle part of the lower conductor rail protrudes into the four-bar mechanism frame, the bending moment at the lower conductor rail load sensor is positive, and at this time the shaft 332 is jammed; on the contrary, when the middle part of the lower conductor rail protrudes out of the four-bar mechanism frame, the bending moment at the lower conductor rail load sensor is negative, and at this time the shaft 333 is jammed.

[0306] In addition, optical fiber strain sensors can be arranged at key stress positions or / and welding seams of the upper arm and the lower arm of the pantograph and the pantograph chassis, which can be used for structural health monitoring of the pantograph frame, and can long-term monitor the fatigue degree of the upper arm, the lower arm and the chassis of the pantograph.

[0307] Further, the optical fiber sensor can include at least one air pressure sensor to collect air pressure signals, and the pantograph can include an air bag and / or an air cylinder (not shown in the figure), a pneumatic control box 35, and an air path pipeline (not shown in the figure) connected to the pneumatic control box 35. The air pressure sensor can be installed at one or more of the following positions: the air bag and / or the air cylinder, the inside or surface of the pneumatic control box 35, and the air path pipeline.

[0308] In the embodiment of the present application, the air pressure sensor can be installed at one or more of the following positions: the air bag and / or the air cylinder, the inside or surface of the pneumatic control box 35, and the air path pipeline, so that the pressure of the air bag or the air cylinder of the pantograph can be monitored according to the air pressure signal, and the lifting pantograph failure can be monitored.

[0309] For monitoring the pressure of the air bag or the air cylinder by coupling the air path pipeline, a tee fitting can be installed on the air path pipeline in the pneumatic control box 35, two ends of the tee fitting are connected to the original air path pipeline, and the remaining one end is connected to the air pressure sensor to monitor the air pressure value in the air bag or the air cylinder of the pantograph in real time.

[0310] For the pantograph ascending and descending failure, some key information such as the air pressure value in the air bag or air cylinder, the ascending height of the pantograph when working, the contact force value between the contact wire and the pantograph head 34, and the tension value and bending moment value of the lower guide rod 321 can be combined to comprehensively analyze and judge the cause of the pantograph ascending and descending failure.

[0311] Further, the air pressure signal can be used to indicate the air pressure value in the pantograph air bag or air cylinder; the processor can determine the air pressure value in the pantograph air bag or air cylinder by using the following formula:

[0312] P A (t)=K A [λ(t)-λ0+k T (T(t)-T0)]

[0313] Wherein, P A (t) is used to indicate the pressure value of the air bag / cylinder at t time, K A is used to indicate the pressure coefficient of the air pressure sensor, λ(t) is used to indicate the wavelength value of the air pressure sensor at t time, λ0 is used to indicate the wavelength value of the air pressure sensor when the air bag / cylinder is not inflated, k T is used to indicate the temperature drift coefficient of the air pressure sensor, T(t) is used to indicate the temperature value at t time, and T0 is used to indicate the temperature value at the initial time.

[0314] It should be pointed out that for the above-mentioned arcing between pantograph and catenary, in specific implementation, the real-time temperature value, current value and air pressure value respectively monitored by the optical fiber current sensor integrated in the acceleration sensor shell, the optical fiber temperature sensor integrated in the contact force sensor shell, and the optical fiber air pressure sensor integrated in the air path of the pneumatic control box can be used to comprehensively determine the generation of arcing between pantograph and catenary.

[0315] For the above-mentioned contact wire height value, the air pressure value in the air bag or air cylinder can be determined based on the pressure value of the air bag / cylinder.

[0316] Further, the air pressure sensor can be embedded with a temperature sensor, or the air pressure sensor can be coupled with a temperature sensor.

[0317] In the embodiment of the application, by arranging the temperature sensor, temperature compensation and real-time temperature sensing can be achieved.

[0318] Further, the pantograph can be selected from a spring box type pantograph, a leaf spring type pantograph and a tension spring type pantograph.

[0319] Specifically, the spring box pantograph can be a pantograph with a spring box type buffer and / or damping system, the leaf spring pantograph can be a pantograph with a leaf spring type buffer and / or damping system, and the tension spring pantograph can be a pantograph with a tension spring type buffer and / or damping system. The spring box pantograph, the leaf spring pantograph, and the tension spring pantograph can be a pantograph with four-support double-carbon slide plates or eight-support four-carbon slide plates, for example, each two supports supporting one carbon slide plate.

[0320] Further, according to whether the pantograph lifting driving device is a gas bag type, a gas cylinder type, or a motor type, the pantograph in the embodiment of the present application can also be divided into a gas bag type pantograph, a gas cylinder type pantograph, or a motor type pantograph. Among them, the motor type pantograph can not measure the gas pressure sensor of the gas bag / gas cylinder.

[0321] Further, the mounting mode of the optical fiber sensor can be selected from screw fastening, embedding, welding, pasting, and implanting.

[0322] Among them, the embedding fixing mode can be that the optical fiber sensor is first embedded in the gap of the inner cavity of the pantograph structure, so as to improve the stability of the optical fiber sensor and save space.

[0323] Among them, the implanting fixing mode can be that the optical fiber sensor is implanted on the surface of the inner wall and / or outer wall of the pantograph structure or / and is first set in the recess, so as to improve the stability of the optical fiber sensor and save space.

[0324] In the embodiment of the present application, the monitoring system can further include an optical fiber signal acquisition processing and analysis unit, which can have a micro scanning laser inside, has the ability to improve the spectral resolution and background noise suppression, realizes the multi-channel synchronous fine scanning of the reflected spectrum signal of the optical fiber sensor, converts the spectrum signal into a standard voltage signal through photoelectric conversion and signal conditioning, completes the analog-digital signal conversion and spectrum analysis by a Field-Programmable Gate Array (FPGA) controlling a multi-channel analog-to-digital (A / D) conversion chip, finally calculates the center wavelength value of each optical fiber sensor, and further calculates the scale factor of the physical quantity-wave length characterization, such as acceleration, contact force, air pressure, temperature coefficient, etc., such as the bending moment coefficient K M-opp,i-opp , the pressure coefficient K A , and finally converts the measured physical value.

[0325] Further, the processor can include an FPGA and a multi-channel analog-to-digital conversion module; wherein the FPGA is configured to control the multi-channel analog-to-digital conversion module to complete analog-to-digital signal conversion and spectral analysis, and output the wavelength value of each optical fiber sensor.

[0326] It should be noted that the wavelength value output by the FPGA can be the wavelength value at which the comb-shaped spectrum output by the optical fiber sensor described above has the maximum light intensity within the bandwidth of the laser. It can be understood that, since only a single peak exists in the comb-shaped spectrum output by the optical fiber sensor in the present application within the bandwidth of the laser, there is only a single wavelength value at which the light intensity is maximum.

[0327] Referring to Figure 13 , Figure 13 is a schematic diagram of a fiber sensing analyzer of a monitoring system using a pantograph in an embodiment of the present application.

[0328] The fiber sensing analyzer can have the characteristics of on-board storage and calculation, and can be installed on a vehicle.

[0329] Specifically, the fiber sensing analyzer can include an FPGA data acquisition and interface communication module 1301, a D / A conversion module 1302, a scanning voltage signal driving circuit 1303, a MEMS micro scanning laser 1304, a 1x2 optical fiber splitter 1305, a 1x32 optical fiber splitter 1306, an optical-electric conversion and signal conditioning 1308, a 36-channel synchronous 25MHz and 16bit A / D conversion array 1309, an industrial computer (storage and calculation integrated information processor) 1310, and a fast pluggable TB capacity solid state storage 1311. Information interaction can also be performed through an optical fiber sensing channel 1307 and a backbone network switch 1312.

[0330] The optical fiber sensing channel 1307 and the optical fiber sensor in the embodiment of the present application can be connected by plugging or welding, and is used as a transceiver port for signals collected, received and fed back by the optical fiber sensor.

[0331] It should be noted that Figure 13 The fiber sensing analyzer shown has good effects in specific applications of the present application, and the specific parameter selection in each module does not constitute a specific limitation on the technical solutions of the present application.

[0332] Specifically, the optical fiber sensing analyzer can internally have an optical fiber signal acquisition processing and analysis unit. The optical fiber signal acquisition processing unit can include a micro scanning laser, such as a MEMS micro scanning laser 1304, which can improve spectral resolution and background noise suppression capability, and realize multi-channel synchronous fine scanning of the optical fiber sensor reflection spectrum signal.

[0333] The 1x2 optical fiber splitter 1305 and the 1x32 optical fiber splitter 1306 can perform splitting processing on the optical signal of the scanning laser, and then use the optical fiber sensing channel 1307 to acquire and analyze the signal of the scanning laser. The specific processing manner can refer to the processing steps of the optical fiber sensor described above, and will not be described here.

[0334] Then, the photoelectric conversion and signal conditioning 1308 can be used to obtain the output signal of the optical fiber sensor. After data processing, the converted data is input into the FPGA data acquisition and interface communication module 1301.

[0335] Specifically, the photoelectric conversion and signal modulation demodulation convert the spectral signal into a standard voltage signal, and the FPGA controls the multi-channel analog-to-digital (A / D) conversion chip to complete analog-to-digital signal conversion and spectral analysis, and finally obtains the center wavelength value of each optical fiber sensor.

[0336] It should be noted that the processor disclosed in the embodiments of the present application can include Figure 13 The FPGA data acquisition and interface communication module 1301, the D / A conversion module 1302, and the 36-channel synchronous 25MHz and 16bit A / D conversion array 1309 shown can also include other appropriate modules, such as the photoelectric conversion and signal conditioning 1308.

[0337] In other specific embodiments of the present application, the processor can also be a central processing unit (CPU). The processor can also be other general-purpose processors, DSPs, application specific integrated circuits (ASICs), or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0338] Further, compared with the digital signal processor (Digital Signal Processor, DSP) usually used in the prior art to collect and process signals, since the DSP can only be applied to multi-condition processes at a relatively low sampling rate or low data rate, especially complex multi-algorithm tasks, it is often difficult to meet the requirements. In the embodiment of the present application, the FPGA is used to collect and process high Gbps signals that the DSP cannot handle, which can better collect and process the massive sampling data at the same time caused by multi-channel synchronous scanning generated by a high-speed scanning laser (a scanning frequency of a general scanning laser is from 1 kHz to 100 kHz, which is a high-speed scanning laser), and can directly output the center wavelength value signal. Therefore, the FPAG is suitable for high sampling frequency, especially in the case of fixed or repeated tasks.

[0339] In the embodiment of the present application, the processor can include an FPGA and a multi-channel analog-to-digital conversion module; wherein the FPGA is used to control the multi-channel analog-to-digital conversion module to complete analog-digital signal conversion and spectral analysis, and output the wavelength value of each optical fiber sensor. Compared with using a digital signal processor to collect and process signals, which can only be applied to multi-condition processes at a relatively low sampling rate or low data rate, multi-algorithm tasks, using an FPGA can collect and process high data rate signals (such as Gbps signals or even higher data rates) that the DSP cannot handle. In this way, it can better collect and process the massive sampling data at the same time caused by multi-channel synchronous scanning generated by a high-speed scanning laser, and can directly output the wavelength value. The wavelength value is the wavelength value at which the comb-shaped spectrum output by the optical fiber sensor has the maximum light intensity within the bandwidth of the laser. Since there is only a single wave peak within the bandwidth of the laser in the comb-shaped spectrum output by the optical fiber sensor in the present application, there is only a single wavelength value at which the light intensity is maximum for output.

[0340] The optical fiber sensing analyzer can also include an industrial computer (storage and computing integrated information processor) 1310, which can directly convert the wavelength signal output by the FPGA into a corresponding physical quantity signal through an embedded algorithm, i.e., a scale factor represented by a physical quantity-center wavelength value, such as an acceleration signal, a contact force signal, a temperature signal, a load signal, a pressure signal, and a deformation signal generated by various sensors installed on the pantograph. Then, combined with the time information and spatial information of the data, the calculated physical quantity signal is recorded in the storage (such as a solid-state storage with a fast plug-in TB capacity 1311) at the same time.

[0341] The memory in the embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically EPROM (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM) used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0342] Specifically, the optical fiber signal acquisition processing and analysis unit with the storage and computing integrated technology can realize the calculation of the spectrum wavelength demodulation to the vibration signal through the built-in ARM CORE and low-latency phase change memory of the FPGA on the basis of realizing the conventional physical quantity sensing measurement of the MEMS optical fiber sensor spectrum wavelength signal demodulation, and further perform FFT signal transformation to realize the frequency domain and time domain signal analysis, and based on the predicted abnormal detection technology, the cycle of the front-end fault model self-learning, prediction and comparison correction is established, and the storage and prediction calculation integration of the internal fault model of the storage and computing integrated optical fiber signal acquisition processing and analysis unit is realized.

[0343] It should be noted that in the specific implementation of the embodiments of the present application, external information such as the vehicle door opening and closing signal can also be obtained through the backbone network switch 1312, thereby improving the accuracy of obtaining the spatial information of the vehicle.

[0344] In the embodiments of the present application, a fiber sensor is also provided, which can be used to receive a laser signal, and can comprise an optical interference cavity, wherein the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and a cavity length of the optical interference cavity satisfies the following formula:

[0345]

[0346]

[0347] wherein, l FP represents the cavity length of the optical interference cavity, k mid represents a preset longitudinal mode number of the fiber sensor, k mid is a positive integer, and k mid ≥2, W laser represents a bandwidth of a laser emitting the laser signal, λ ctr represents a center wavelength value of the bandwidth of the laser; the optical interference cavity comprises two mirrors located at two ends of a cavity, and the cavity length of the optical interference cavity is a distance between the two mirrors.

[0348] The cavity length of the optical interference cavity can satisfy the following formula:

[0349]

[0350] wherein, l ctr represents the cavity length of the optical interference cavity.

[0351] In the embodiments of the present application, according to the bandwidth of a laser emitting the laser signal, the center wavelength value of the bandwidth of the laser and the preset longitudinal mode number of the fiber sensor, the cavity length of the optical interference cavity can be determined by using a formula, so that only a single wave peak in the comb-shaped spectrum output from the optical interference cavity is located within the bandwidth of the laser, thereby avoiding signal interference of adjacent wave peaks on the wave peak in the analysis process, and effectively preventing code stringing.

[0352] The principle, specific implementation and beneficial effects of the fiber sensor are described above with reference to the related description of the monitoring system of the pantograph, and will not be repeated here.

[0353] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art, without departing from the spirit and scope of the present application, can make various changes and modifications, and therefore the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A monitoring system of a pantograph, characterized by, The power supply pantograph comprises: one or more optical fiber sensors mounted on the pantograph for receiving laser signals; a processor coupled with the optical fiber sensors for processing signals collected by the optical fiber sensors; wherein the optical fiber sensor has an optical interference cavity, the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and the cavity length of the optical interference cavity satisfies the following formula: ， wherein for representing a cavity length of the optical interference cavity, for representing a preset longitudinal mode number of the fiber-optic sensor, is a positive integer, and ≥ 2, for representing a bandwidth of a laser emitting the laser signal, for representing a center point wavelength value of the bandwidth of the laser. The optical interference cavity comprises mirrors at both ends of the cavity, and the cavity length of the optical interference cavity is the distance between the two mirrors. The optical fiber sensor comprises at least one contact force sensor for collecting pressure signals, the pressure signals are used to indicate the pantograph-catenary contact force between the pantograph head and the contact wire, and are used to monitor the contact wire hard point, the pull-out value, the pantograph-catenary contact force, the impact and the arc. The optical fiber sensor further comprises at least one acceleration sensor for collecting acceleration signals, the acceleration signals are used to indicate the acceleration of at least one pantograph head in the transverse direction and the acceleration of at least one pantograph head in the vertical direction. The optical fiber sensor comprises at least one air pressure sensor for collecting air pressure signals, when the pantograph lifting electromagnetic valve is powered on, one branch of compressed air inflates the air bag of the pantograph, and at the same time, the other branch inflates the air cavity of the carbon slide plate of the pantograph.

2. The monitoring system of a pantograph according to claim 1, characterized in that, The cavity length of the optical interference cavity satisfies the following formula: ， wherein, for representing a cavity length of the optical interference cavity.

3. The monitoring system of a pantograph according to claim 1, characterized in that, The pantograph comprises one or more pantograph heads, and each pantograph head comprises a pantograph head support. For the pantograph head provided with the contact force sensor, the contact force sensor is mounted on the inside or surface of the pantograph head support.

4. The monitoring system of a pantograph according to claim 3, characterized in that, The contact force sensors are arranged in pairs, and the contact force sensors in each pair are mounted on the pantograph head supports at both ends of the same pantograph head.

5. The monitoring system of a pantograph according to claim 3, characterized in that, The pantograph head supports and the contact force sensors correspond to each other, and each pantograph head support has a corresponding contact force sensor mounted on the inside or surface thereof.

6. The monitoring system of a pantograph according to claim 3, characterized in that, The contact force sensor has a temperature sensor embedded therein or coupled thereto.

7. The monitoring system of a pantograph according to claim 3, characterized in that, The pressure signals are used to indicate the quality of the carbon slide plate structure of the pantograph. The processor determines the abrasion amount of the carbon slide plate structure by using the following formula: ， wherein, G for representing the initial mass of the i-th carbon slide structure when it is not worn out, ’ 0,i K for representing the mass of the i-th carbon slide structure at time t, G,i,j λ for representing the contact force coefficient of the j-th contact force sensor of the i-th carbon slide structure, D,i,j λ for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure when it is not under any force, CS,i,j λ for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure when the i-th carbon slide structure is not worn out, ’ CS,i,j N for representing the wavelength value of the j-th contact force sensor of the i-th carbon slide structure at time t, S i for representing the number of the contact force sensors on the same carbon slide, i for representing the serial number of the carbon slide structure, and j for representing the serial number of the contact force sensor of each carbon slide structure.

8. The monitoring system of a pantograph according to claim 3, characterized in that, The pressure signals are used to indicate the pantograph-catenary contact force between the pantograph head and the contact wire. The processor determines the pantograph-catenary contact force between the pantograph head and the contact wire by using the following formula: ， Wherein, F S,i,j (t) is used to represent the contact force value between the contact force sensor on the jth pantograph support of the ith group of carbon slide plates of the pantograph head and the contact wire at time t, K S,i,j is used to represent the contact force coefficient of the jth contact force sensor of the ith group of carbon slide plates, λ i,j (t) is used to represent the wavelength value of the jth contact force sensor of the ith group of carbon slide plates at time t, λ0, i,j is used to represent the wavelength value of the jth contact force sensor of the ith group of carbon slide plates when the pantograph head of the pantograph has no mutual force interaction with the contact wire, k T,i,j is used to represent the temperature drift coefficient of the jth contact force sensor of the ith group of carbon slide plates, T(t) is used to represent the temperature value at time t, T0 is used to represent the temperature value at the initial time, F cp (t) is used to represent the contact force value between the pantograph head and the contact wire at time t, N C is used to represent the number of carbon slide plates on the pantograph head, N S is used to represent the number of pantograph supports on the same group of carbon slide plates.

9. The monitoring system of a pantograph as claimed in claim 1, characterized in that, The pantograph comprises one or more pantograph heads, and each pantograph head comprises a carbon slide plate, pantograph head supports respectively connected to both ends of the carbon slide plate, and a connecting component for connecting the carbon slide plate and the pantograph head supports. For the pantograph head provided with the acceleration sensor, the acceleration sensor is mounted on one or more of the following: the inside or surface of the pantograph head support, and the connecting component.

10. The monitoring system of a pantograph according to claim 9, characterized in that, The acceleration sensors are arranged in pairs. The acceleration sensors in each pair are mounted on the pantograph head supports at both ends of the same pantograph head, or the acceleration sensors in each pair are mounted on the connecting components at both ends of the same pantograph head.

11. The monitoring system of a pantograph as claimed in claim 9, characterized in that, The pantograph head supports and the acceleration sensors correspond to each other, and each pantograph head support has a corresponding acceleration sensor mounted on the inside or surface thereof.

12. The monitoring system of a pantograph according to claim 9, characterized in that, The acceleration sensor is a fiber-optic three-axis acceleration sensor.

13. The monitoring system of a pantograph according to any one of claims 9 to 12, characterized in that, The acceleration sensor is internally embedded with a current sensor, or the acceleration sensor is coupled with a current sensor.

14. The monitoring system of the pantograph according to claim 9, wherein the processor determines the vertical and lateral vibration displacement of the pantograph head by using the following formula:

15. The monitoring system of the pantograph according to claim 9, wherein the fiber-optic sensor further comprises at least one contact force sensor for collecting a pressure signal, the pantograph comprises one or more pantograph heads, each of which comprises a pantograph head support; for the pantograph head with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support; ， wherein, d H (t) is used to represent the displacement value of the pantograph head in the lateral direction at time t, d 0,H is used to represent the initial displacement value of the pantograph head in the lateral direction, v 0,H is used to represent the initial velocity value of the pantograph head in the lateral direction, a H (t) is used to represent the acceleration value of the pantograph head in the lateral direction at time t, d V (t) is used to represent the displacement value of the pantograph head in the vertical direction at time t, d 0,V is used to represent the initial displacement value of the pantograph head in the vertical direction, v 0,V is used to represent the initial velocity value of the pantograph head in the vertical direction, a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t. The processor determines the acceleration value of the pantograph head in the vertical direction and the pantograph-catenary interface contact force between the pantograph head and the contact wire by using the following formula:

16. The monitoring system of the pantograph according to claim 9, wherein the fiber-optic sensor further comprises at least one contact force sensor for collecting a pressure signal, the pantograph comprises one or more pantograph heads, each of which comprises a pantograph head support; for the pantograph head with the contact force sensor, the contact force sensor is installed inside or on the surface of the pantograph head support; The pressure signal is used to indicate the pantograph-catenary interface contact force between the pantograph head and the contact wire; ， wherein a V (t) is used to represent the acceleration value of the pantograph head in the vertical direction at time t, K V is used to represent the acceleration coefficient of the acceleration sensor in the vertical direction, λ V (t) is used to represent the wavelength value of the acceleration sensor in the vertical direction at time t, λ 0,V is used to represent the wavelength value of the acceleration sensor in the vertical direction in the static state, k T,V is used to represent the temperature drift coefficient of the acceleration sensor in the vertical direction, F S (t) is used to represent the contact force value between the contact force sensor and the contact wire at time t, K S is used to represent the contact force coefficient of the contact force sensor, λ S (t) is used to represent the wavelength value of the contact force sensor at time t, λ0, S is used to represent the wavelength value of the contact force sensor when the pantograph head has no interaction with the contact wire, k T,S is used to represent the temperature drift coefficient of the contact force sensor, T(t) is used to represent the temperature value T at time t, and T0 is used to represent the temperature value at the initial time. The acceleration signal is used to indicate the acceleration of at least one pantograph head in the longitudinal direction; The processor determines the pull-out value of the contact wire by using the following formula: Or, The acceleration signal is used to indicate the acceleration of at least one pantograph head in the vertical direction; The processor determines the gauge value of the contact wire by using the following formula: ， The fiber-optic sensor comprises at least one temperature sensor for collecting a temperature signal, the pantograph comprises one or more pantograph heads, each of which comprises a carbon slide, a pantograph head support connected to each end of the carbon slide, and a connecting component for connecting the carbon slide and each pantograph head support; ， Wherein, Z C (t) is the pull-out value of the contact wire at time t, defined as the distance between the right side of the train in the direction of travel Z C is negative, and the left side of the train in the direction of travel Z C is positive, L S is the distance between the centers of the two head supports with buffer or / and damping system at both ends of the same group of carbon slides, F S,i,drg and F S,i,gch respectively represent the contact force value between the contact force sensor on the right and left head supports of the i-th group of carbon slides of the pantograph head and the contact wire at time t, v L (t) is used to represent the speed value of the pantograph head in the longitudinal direction at time t, v 0,L is used to represent the initial speed value of the pantograph head in the longitudinal direction, a L (t) is used to represent the acceleration value of the pantograph head in the longitudinal direction at time t a L , D L (t) is used to represent the travel distance of the train at time t, D 0,L is used to represent the initial travel distance of the train.

17. The monitoring system of a pantograph as claimed in claim 9, characterized in that, For the pantograph head with the temperature sensor, the temperature sensor is installed at one or more of the following locations: Inside or on the surface of the pantograph head support, on the connecting component. ， wherein, v V (t) is used to represent the value of the vertical direction speed of the pantograph head at time t, v 0,V is used to represent the value of the initial speed of the vertical direction of the pantograph head, a V (t) is used to represent the value of the vertical direction acceleration of the pantograph head at time t, h C (t) is used to represent the value of the contact wire height at time t, h Tr is used to represent the height of the roof of the car in which the pantograph is located relative to the ground, h cp,0 (P A,0 ) is used to represent the height of the upper surface of the pantograph head carbon slide relative to the roof when the air bag pressure value is P A,0 , P A,0 is used to represent the air bag pressure value in the static pantograph-raising state when the pantograph-catenary contact force required during normal current collection is P 18. The monitoring system of a pantograph as claimed in claim 1, characterized in that, The fiber-optic sensor comprises at least one current sensor for collecting a current signal, the pantograph comprises one or more pantograph heads, each of which comprises a carbon slide, a pantograph head support connected to each end of the carbon slide, and a connecting component for connecting the carbon slide and each pantograph head support; For the pantograph head with the current sensor, the current sensor is installed at one or more of the following locations: Inside or on the surface of the pantograph head support, on the connecting component.

19. The monitoring system of a pantograph as claimed in claim 1, characterized in that, The fiber-optic sensor comprises at least one load sensor for collecting a load signal, the pantograph comprises a four-bar linkage structure; The load sensor is installed at one or more of the following locations: Upper arm of the four-bar linkage structure, lower arm of the four-bar linkage structure, lower guide rod of the four-bar linkage structure.

20. The monitoring system of a pantograph as claimed in claim 1, characterized in that, The load sensor is internally embedded with a temperature sensor, or the load sensor is coupled with a temperature sensor.

22. The monitoring system of the pantograph according to claim 20, wherein ​ 21. The monitoring system of a pantograph as claimed in claim 20, characterized in that, ​ ​ The load sensor is installed on the same cross section circumference of any cross section of the lower guide rod, and the load signal is used to indicate the tension of the lower guide rod. The processor determines the tension value of the lower guide rod by using the following formula: ， wherein F pf (t) is used to represent the tension value of the lower guide rod at time t, N is used to represent the total number of load sensors on the same cross section of the lower guide rod, K pf,n is used to represent the tension coefficient of the nth optical fiber load sensor, λ n (t) is used to represent the wavelength value of the nth load sensor at time t, λ 0,n is used to represent the wavelength value of the nth optical fiber load sensor under no load, k T,n is used to represent the temperature drift coefficient of the nth optical fiber load sensor, T(t) is used to represent the temperature value at time t, and T0 is used to represent the temperature value at the initial time.

23. The monitoring system of the pantograph according to claim 20, wherein, The load sensor is installed on the same cross section circumference of any cross section of the lower guide rod, and the load signal is used to indicate the bending moment of the lower guide rod. The processor determines the bending moment value of the lower guide rod by using the following formula: ， wherein , wherein, M i,i-opp (t) is used to represent the bending moment value of the ith, i-opp bending direction of the lower guide rod at time t, N is used to represent the total number of load sensors on the same cross section of the lower guide rod, I is used to represent the pairing number of two opposite load sensors on the same cross section of the lower guide rod, K M,i is used to represent the bending moment coefficient of the ith load sensor of the lower guide rod, λ i (t) is used to represent the wavelength value of the ith fiber load sensor at time t, λ0, i is used to represent the wavelength value of the ith fiber load sensor under no load, k T,i is used to represent the temperature drift coefficient of the ith fiber load sensor, K M-opp,i-opp is used to represent the bending moment coefficient of the fiber load sensor opposite to the ith fiber load sensor of the lower guide rod, λ opp , i-opp (t) is used to represent the wavelength value of the i-opp fiber load sensor opposite to the ith fiber load sensor at time t, λ 0-opp,i-opp is used to represent the wavelength value of the i-opp fiber load sensor opposite to the ith fiber load sensor under no load, k T-opp,i-opp is used to represent the temperature drift coefficient of the i-opp fiber load sensor opposite to the ith fiber load sensor, T(t) is used to represent the temperature value at time t, T0 is used to represent the temperature value at the initial time.

24. The monitoring system of a pantograph as claimed in claim 1, characterized in that, The optical fiber sensor comprises at least one strain sensor for collecting deformation signals, and the pantograph comprises a four-bar linkage structure and a chassis; The strain sensor is installed at one or more of the following positions: The upper arm of the four-bar linkage structure, the lower arm of the four-bar linkage structure, the lower guide rod of the four-bar linkage structure, and the chassis.

25. The monitoring system of the pantograph according to claim 1, wherein, The pantograph further comprises a pneumatic control box and a gas path pipeline connected to the pneumatic control box. The gas pressure sensor is installed at one or more of the following positions: The gas bag, the inside or surface of the pneumatic control box, and the gas path pipeline.

26. The monitoring system of a pantograph as claimed in claim 25, characterized in that, The gas pressure sensor is internally embedded with a temperature sensor, or the gas pressure sensor is coupled with a temperature sensor.

27. The monitoring system of a pantograph as claimed in claim 25, characterized in that, The gas pressure signal is used to indicate the air pressure value in the gas bag of the pantograph. The processor determines the air pressure value in the gas bag of the pantograph by using the following formula: ， wherein P A (t) is used to represent the pressure value of the airbag at time t, K A is used to represent the pressure coefficient of the air pressure sensor, λ(t) is used to represent the wavelength value of the air pressure sensor at time t, λ0 is used to represent the wavelength value of the air pressure sensor when the airbag is not inflated, k T is used to represent the temperature drift coefficient of the air pressure sensor, T(t) is used to represent the temperature value at time t, and T0 is used to represent the temperature value at the initial time.

28. The monitoring system of a pantograph as claimed in claim 1, characterized by, The pantograph is selected from a spring box type pantograph, a leaf spring type pantograph, and a tension spring type pantograph.

29. The monitoring system of a pantograph as claimed in claim 1, characterized by, The installation mode of the optical fiber sensor is selected from: Screw fastening, embedding, welding, sticking, and implanting.

30. The monitoring system of a pantograph as claimed in claim 1, wherein, The processor comprises an FPGA and a multi-channel analog-to-digital conversion module. The FPGA is used to control the multi-channel analog-to-digital conversion module to complete analog-digital signal conversion and spectral analysis, and output the wavelength values of each optical fiber sensor.

31. An optical fiber sensor, characterized by, The optical fiber sensor is used to receive a laser signal, and the optical fiber sensor comprises: An optical interference cavity, the laser signal forms a comb-shaped spectrum after entering the optical interference cavity, and the cavity length of the optical interference cavity satisfies the following formula: ， wherein, for representing a cavity length of the optical interference cavity, for representing a preset longitudinal mode number of the fiber-optic sensor, is a positive integer, and ≥ 2, for representing a bandwidth of a laser for emitting the laser signal, for representing a center point wavelength value of the bandwidth of the laser. The optical interference cavity comprises mirrors at both ends of the cavity, and the cavity length of the optical interference cavity is the distance between the two mirrors. The optical fiber sensor comprises at least one contact force sensor for collecting pressure signals, the pressure signals are used to indicate the pantograph-catenary contact force between the pantograph head and the contact wire, and are used to monitor the contact wire hard point, the pull-out value, the pantograph-catenary contact force, the impact, and the arcing; The optical fiber sensor further comprises at least one acceleration sensor for collecting acceleration signals, the acceleration signals are used to indicate the acceleration of at least one pantograph head in the transverse direction and the acceleration of at least one pantograph head in the vertical direction. The optical fiber sensor comprises at least one air pressure sensor for collecting air pressure signals, when the pantograph lifting electromagnetic valve is energized, one branch of compressed air inflates the gas bag of the pantograph, and at the same time, the other branch inflates the air cavity of the carbon slide of the pantograph.

32. The fiber optic sensor of claim 31, wherein, The cavity length of the optical interference cavity satisfies the following formula: ， wherein, for indicating a cavity length of the optical interference cavity.

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