Railway vehicle control loop online information acquisition and failure early warning method

Abstract

The invention discloses a railway vehicle control loop on-line information acquisition and failure early warning method, and the method comprises the steps: building a novel railway vehicle control loop on-line information acquisition system through reasonable information acquisition design, including reasonable measurement point arrangement, key period analog quantity acquisition and data screening; the invention further provides a rail vehicle control loop failure early warning method, so that rail vehicle failure prediction is more accurate, and sudden failures and heavy losses caused by the sudden failures can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of rail vehicle control, and in particular to a rail vehicle control loop online information collection and failure warning method. Background Art

[0002] The control circuit of rail vehicles is generally composed of switches, buttons, relays, cables, connectors and other parts. Among them, relay contacts are important components for controlling the on and off of the circuit. Since the terminal load of the control circuit is mainly the coil, the arcing effect generated by the reverse electromotive force often causes the material transfer of the relay contact. When the material transfer accumulates to a certain extent, it may develop into faults such as contact adhesion, which will cause the control circuit logic disorder and affect the operation order.

[0003] There are currently three main technical means for relay contact failure diagnosis: (1) Fault diagnosis based on switch quantity acquisition Collect the voltage of the contact input and output terminals, and then combine it with the coil status to determine whether the contact action is normal. It can identify the fault of the contact not being broken when it should be broken, or not being closed when it should be closed. This method is generally used for online diagnosis, and it is necessary to combine the action sequence of the control circuit to determine whether the state is abnormal.

[0004] (2) Fault diagnosis based on analog threshold By detecting the parameters marked in the relay technical specification, such as: pull-in voltage, release voltage, action time, contact resistance, etc., the threshold is set to determine whether the relay status is qualified. This method is generally used for offline diagnosis, and different thresholds need to be set for different types of relays.

[0005] (3) Lifespan prediction based on big data algorithms Collect a large amount of raw data, study the changing trends of certain parameters on this basis, and then form a life curve. This method requires data of a large number of relays of the same model, and currently some research has been mainly carried out in a laboratory environment.

[0006] However, the above three types of technical means are currently unable to achieve online failure warning (prejudgment) of rail vehicle control circuits, among which: (1) Switching quantity diagnosis is limited by the acquisition capability (for example, the optocoupler can only be turned on and off, and the sampling period is too long). It is unable to capture the waveform at the moment when the circuit is turned on and off. It can only identify faults but cannot predict failures.

[0007] (2) The setting of analog thresholds and the trend judgment of big data algorithms cannot be carried out on specific actual circuits. Even if a certain prediction can be achieved, its essence is more of a judgment on the failure probability of batch products.

[0008] Therefore, existing technical means are not suitable for guiding the prediction of circuit failures during rail vehicle operation, and cannot effectively prevent the impact of occasional failures on operational order. Summary of the invention

[0009] The purpose of the present invention is to overcome the defects existing in the prior art, construct a new type of rail vehicle control loop online information collection system through reasonable information collection design, including reasonable measurement point arrangement and analog quantity collection during key periods, and provide a rail vehicle control loop failure warning method, so as to make rail vehicle fault prediction more accurate and avoid sudden failures and the heavy losses caused by them.

[0010] To achieve the above object, the present invention provides a method for collecting online information of a rail vehicle control loop, the method comprising: S1. Measurement point arrangement: the electrical circuit is used as the information collection unit, and at least one measurement point is designed for each branch of the circuit; S2, information collection, the information collection includes analog voltage collection and / or analog current collection, and the collection method includes timed collection at each measuring point and / or rotation collection, which are specific methods of real-time collection; S3, data screening, including recording and storing the analog rising edge and / or falling edge data, recording and storing the analog data for a period of time before and after the threshold in a threshold triggering manner, that is, there is no need to record the complete current and / or voltage time-varying data of the contacts; the rising edge includes the moment when the coil is energized, and the falling edge includes the moment when the coil is de-energized.

[0011] Furthermore, the measuring points mainly include the source of the vehicle control instructions and / or the terminal loads of all electrical branches. The source of the vehicle control instructions includes switches, buttons or remote instructions, etc., and the terminal loads of the electrical branches include the coils of relays or solenoid valves, etc.

[0012] Furthermore, the sampling frequency of the information collection is greater than or equal to 200kHz, so that the factors that may cause failure can be accurately reproduced. The voltage sampling accuracy is better than 1V and the current sampling accuracy is better than 10mA, otherwise the amplitude of the waveform change cannot be effectively identified.

[0013] Furthermore, the voltage acquisition needs to be one-to-one, that is, each terminal load corresponds to a voltage acquisition port; the current acquisition can be shared by multiple branches, that is, the change of the corresponding branch current is determined by the change of the voltage state and the current amplitude.

[0014] Furthermore, the threshold trigger includes carrying out voltage collection when the rising edge amplitude is greater than or equal to 1 / 20 of the rated working voltage or the falling edge amplitude is less than or equal to 4 / 5 of the rated working voltage, and carrying out current collection when the rising edge amplitude is greater than or equal to 1 / 10 of the rated working current or the falling edge amplitude is less than or equal to 4 / 5 of the rated working current; the period of time is less than or equal to the continuous change time from the minimum value to the maximum value or from the maximum value to the minimum value.

[0015] Furthermore, the data screening also includes taking a single channel as a processing object and counting the data of its trend changes over time; and taking the control timing during vehicle operation as a processing object and counting the data of trend changes of multiple channels at a certain moment or over a certain period of time.

[0016] On the other hand, a rail vehicle control loop online information collection system, a system constructed according to any one of the rail vehicle control loop online information collection methods described above, includes an information collection device and a control processing device.

[0017] On the other hand, for any system capable of acquiring time-varying information of current and / or voltage of a rail vehicle control loop, in particular for the above-mentioned rail vehicle control loop online information acquisition system, it is characterized in that the failure warning method includes a self-comparison judgment method of the own vehicle or a mutual comparison judgment method of different vehicles: The vehicle self-comparison judgment method includes taking the data of a certain electrical branch of the vehicle as a benchmark, comparing and analyzing the change trends under different seasons and different mileages, and identifying the mutation points under the same working conditions (such as similar time periods and the same functional operations); The method of comparing different vehicles includes taking the data of different trains and the same loop as a benchmark, comparing the change trends under the same working conditions or within the same day, and identifying the differences therein. The difference point judgment can be the same as the mutation point judgment method; the different vehicles generally refer to different trains of the same batch.

[0018] Furthermore, the failure warning judges the state change of each electrical branch and the principle of the cause of the state change, including any of the following items: ① Uniqueness principle: at any moment, only one functional state combination meets the design requirements; ② Association principle: Any state combination is determined by the previous state combination, that is, all circuits operate in sequence; ③ Duration parameter judgment principle: For channels that meet the above-mentioned uniqueness principle and association principle, it means that the timing control of each electrical branch is normal, and then it is necessary to screen whether there are abnormalities in parameters such as the action duration, and locate the abnormal components according to the correspondence between each channel and the actual vehicle circuit (such as: a group of contacts of a relay is sticky); for channels that do not meet the above principles, it means that there are occasional factors such as interference and poor contact, and it is necessary to focus on checking the connection status of the corresponding electrical branch.

[0019] Furthermore, the failure warning includes warnings of contact adhesion, contact sticking, poor contact, poor insulation or solenoid valve failure, which are also called warnings of degradation characteristics.

[0020] The advantages and beneficial effects of the present invention are as follows: the present invention realizes online failure prediction under the operating conditions of the existing vehicle circuit from three aspects: the online information collection method of the rail vehicle control circuit, the system design, and the online diagnosis and early warning (prejudgment) method, thereby greatly reducing or even basically eliminating the probability of occasional failures such as relay contact failure and poor connector contact affecting the vehicle operation and operating order, especially the probability of causing sudden accidents with significant impacts. Furthermore, the present invention has the following specific effects: (1) Accurate state reproduction The action time of relay contacts is generally in the ms level, but most of its characteristic values ​​are in the μs level, such as contact jitter, contact arcing, etc.

[0021] The online sampling frequency of the present invention is set to above 200kHz, which can accurately reproduce the voltage and current fluctuations at the moment of contact action, thereby ensuring that failure hazards can be reliably identified.

[0022] As the sampling frequency increases, the amount of data increases sharply. The wave recording function not only occupies a large amount of storage space, but also masks the effective data, resulting in low processing efficiency. Therefore, the data pre-screening method proposed in the present invention only stores transient data related to failures, which can not only greatly save storage space, but also effectively improve data processing efficiency.

[0023] In addition, in order to facilitate online real-time observation, the present invention specially designs a human-machine interface, which can batch manage the waveform display function of each channel, making it convenient for users to use.

[0024] (2) Accurately locate hidden dangers The existing technology mainly diagnoses a single relay and sets a unified threshold to determine whether there is an abnormality. However, the rail vehicle control circuit is usually a relay with multiple contacts distributed in different circuits, and the electrical characteristics of each circuit vary greatly. Therefore, the existing technology cannot evaluate the actual operating conditions of the vehicle. In addition, the existing diagnostic device only focuses on the waveform changes of a single channel. On the one hand, the coverage of the measurement points is not wide due to the limited number of channels. On the other hand, it does not understand the logical relationship between the various control circuits of the vehicle. Therefore, when an abnormality is found, it is impossible to accurately locate the source of the fault, and it is necessary to return to the warehouse to check one by one to locate the real fault point.

[0025] Based on the accurate reproduction of transient waveforms, the present invention realizes accurate identification and location of hidden dangers through the following measures: ① Extract characteristic values ​​according to different failure modes, and process the collected voltage and current data into various indicators to characterize degradation.

[0026] Taking contact adhesion as an example, this type of failure mode can be characterized by the contact action time. As long as the time difference exceeds the limit, it can be determined that there is a potential adhesion hazard. See the previous text for details. Taking poor insulation as an example, as long as the current amplitude exceeds the standard, it can be determined as a leakage hazard. Only by matching failure modes with specific parameters one by one can it be possible to specify evaluation criteria, and the determination of specific indicators requires combining actual operating data on this basis, at least one model for one region, or even one model for one line. There are many research results on the parameters corresponding to the failure mode, but these results are not combined with actual data. Only by collecting real data under different working conditions can these results be applied. This is the advantage of the present invention.

[0027] ② Optimize the correspondence between measurement points and acquisition channels, and use electrical branches as test objects to achieve full coverage of status acquisition of all control circuits of the vehicle.

[0028] The measuring points of the present invention can collect the terminal loads (mainly coils) of all circuits of the whole vehicle, so any problem in any circuit will be recorded, and full coverage of the status collection of all control circuits of the whole vehicle can be achieved. It should be noted here that the number of control circuits and the mechanical structures to be driven by the control circuits (such as motors, gas circuits, etc.) are basically unchanged, but the logical relationships of the control circuits vary greatly, such as high-speed rail, subway, urban trains, etc. If the status of all contacts is collected, the number of measuring points set is uncontrollable and there will be a lot; if the status of the terminal load of the circuit is collected, the work of the number of measuring points, on-site vehicle construction, troubleshooting, etc. will be much simpler.

[0029] It can be understood as follows: the existing technology realizes positioning by collecting contact status, and can immediately identify the fault point. For example, if there is voltage at the input end of a certain contact and no voltage at the output end, it means that the contact is not closed, and its fault positioning does not require any algorithm, because each measuring point corresponds to a collection port. However, the present invention only collects the state of the terminal load, and its state change is controlled by multiple contacts. Therefore, it needs to be located in combination with the logical relationship of the vehicle control loop. The algorithm is relatively complex, but the advantage is that it saves measuring points and is convenient for modular configuration.

[0030] ③ Combined with the logical relationship of the rail vehicle control loop, the transient data of a certain period of time is screened out to extract the timing relationship between each channel. If a certain state data is found to be abnormal, the source of the abnormality can be accurately located by reversing the timing relationship; and then it is found that this state is an occasional phenomenon of a certain channel, which means that the cause of the fault lies in the line connection. In this way, the hidden dangers can be accurately located and the efficiency of hidden danger disposal can be improved.

[0031] The normal timing relationship is recorded in combination with the vehicle function debugging. Once the vehicle is produced, the timing relationship is fixed. That is, the corresponding relationship of all relays, switches and other logical devices in the control loop is fixed. For example, a button energizes a certain loop, and then this loop will definitely cause several other loops to be energized or de-energized. This corresponding relationship cannot be changed. Therefore, a certain loop has multiple contacts driving together. These contacts must be closed to energize the terminal load, and any contact disconnection will cause the terminal load to lose power. Whether the terminal load is energized or de-energized, at that moment it must be accompanied by the energization or de-energization of other loops (that is, the coil corresponding to the contact in this loop), so you can know which relay energizes or de-energizes this loop. If this loop is activated again at other times, it will definitely be accompanied by the energization or de-energization of other loops. This is the strategy of precise positioning.

[0032] Any relay corresponds to at least two circuits, coil and contact. Therefore, any relay that is powered on or off will definitely cause at least two circuits to change. If only the circuit corresponding to a certain channel changes, it means that the change is not caused by the relay. Otherwise, there can only be problems with the line connection, including cables, connectors, crimping terminals, etc. The reason why it is called an occasional phenomenon is the conclusion drawn from operational experience. The influence of factors such as vibration during operation will cause occasional poor contact. Such faults cannot be identified in the static state of the library.

[0033] (3) Failure prediction guides operation and maintenance Affected by factors such as the environment and working conditions, even if the control loop is normal, there is a possibility of data fluctuations. In order to avoid false alarms affecting the operating order, the existing technology adopts a unified threshold alarm setting method, and the threshold has a large fault tolerance range. This method is simple and easy to implement, but the probability of missed alarms is very high, and when the threshold alarm is reached, due to the lack of accurate waveform reproduction ability, it is impossible to accurately judge whether it is a false alarm or an actual occurrence. Therefore, it is impossible to effectively guide operation and maintenance, that is: if it is considered to be a real alarm, the faulty part must be replaced preventively, and if it is considered to be a false alarm, it may cause a failure during operation.

[0034] Through online monitoring, the present invention can accumulate all state change data in different operating conditions and with the increase of running mileage. On this basis, it can summarize and screen the characteristic change rules of each electrical branch to achieve one-to-one precise management. This can effectively identify different factors such as normal wear, occasional interference, abnormal degradation, etc., so as to guide users to make precise policies and continuously optimize operation and maintenance strategies.

[0035] Different failure modes correspond to different characteristic values. The changing rules corresponding to normal wear, occasional interference, and abnormal degradation are different. This requires the accumulation of data, manual analysis, and then the final determination of the judgment criteria. From current experience, manual analysis is very easy to identify the degradation caused by different factors. The key lies in the accuracy of the original data. Of course, realizing intelligent and automatic identification is not within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a flow chart of the online information collection method of the present invention; Figure 2 It is a schematic diagram of the arrangement of measuring points in the prior art; Figure 3 It is a schematic diagram of the measurement point arrangement of the present invention. DETAILED DESCRIPTION

[0037] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0038] Embodiment 1: like Figure 1 As shown, the present invention designs a method for collecting online information of a rail vehicle control loop, and the collection method comprises: S1. Measurement point arrangement, with the electrical circuit as the information collection unit, at least one measurement point is designed for each branch of the circuit; the circuit refers to a complete circuit that completes a function, and the branch refers to a control logic circuit in the circuit; each electrical branch is generally controlled by multiple contacts. The current common technology is to collect the input and output status of each contact, which leads to an extremely large number of measurement points. When the measurement point coverage is not high, it is impossible to achieve accurate positioning of the full-column control circuit; a single channel refers to a voltage acquisition port in the information acquisition or diagnostic device, corresponding to a specific electrical branch (i.e.: the positive pole of the terminal load of this circuit). The present invention takes the overall perspective of the rail vehicle, regards all electrical circuits as a whole, and sets measurement points (information collection points) based on the logical control relationship between each other, so as to achieve failure prediction and accurate positioning of each electrical branch. The measurement point generally focuses on the end of the electrical branch (i.e.: the connection part between the last group of contacts in the circuit and the positive pole of the terminal load leads to the measurement point).

[0039] like Figure 2 As shown in the figure, it is the measurement point arrangement of the existing commonly used technology. Its characteristics are that the measurement points are drawn from the bottom of each contact, with a total of 5 measurement points, and generally digital quantity acquisition. The advantage of this method is that the specific fault point of each line can be accurately located. However, due to the limitations of sampling frequency and the fact that digital quantity can only identify on and off, this method can only be used to locate the fault after it occurs, and cannot identify the process of degradation development, and thus cannot achieve failure prediction.

[0040] Figure 3 The measurement point arrangement of the present invention is shown, which is characterized by leading out measurement points at the load of each circuit terminal, requiring only 3 measurement points, and adopting high sampling frequency and high-precision analog quantity acquisition, which can effectively save the number of measurement points. The present invention can identify circuits that may have hidden dangers in advance through real-time trend changes, and then combine the measurement point acquisition method of existing technology to temporarily lead out measurement points in various links of the circuit, thereby realizing accurate positioning of hidden dangers. Since the present invention can realize failure prediction, there is enough time to conduct step-by-step and accurate investigation before the degradation develops into a fault.

[0041] S2. Information collection, which includes analog voltage collection and / or analog current collection. The collection methods include timed collection at each measuring point and / or rotational collection. Both real-time collection methods can be used. A general control loop is composed of contacts, circuits, coils and other links, and its state change can be equivalent to 1, 0, that is, the switch state. Analog quantity collection is the key difference between the present invention and traditional rail vehicle control switch quantity collection, because the switch quantity can only determine the on-off state of the measuring point (contact), and it is difficult to reflect the performance of the contact. The time-varying characteristics of the analog quantity can well reflect the changes in the electrical performance of the contact, thereby providing basic information for failure warning.

[0042] S3, data screening, including recording and storing the analog rising edge and / or falling edge data, recording and storing the analog data for a period of time before and after the threshold in a threshold triggering manner, that is, there is no need to record the complete current and / or voltage time-varying data of the contacts; the rising edge includes the moment when the coil is energized, and the falling edge includes the moment when the coil is de-energized.

[0043] High precision, high sampling rate, and multi-channel acquisition will lead to a significant increase in data volume. On the one hand, it places high demands on processor capabilities, storage space and other performance requirements. On the other hand, the preprocessing of huge amounts of data also brings challenges.

[0044] The present invention mainly focuses on the fluctuation of voltage and current, which is the key factor causing circuit failure. Therefore, the analog acquisition port uses threshold triggering to record data, that is, when a rising edge or a falling edge is detected, the data of a period of time before and after is stored, and the data when the circuit is in a stable state does not occupy storage space.

[0045] The key factors of contact failure are mainly concentrated in the moment of power on and power off, while the stable state after the contact is closed and disconnected is invalid data. In order to save storage space, when recording the state, the present invention stores all the state data of 50ms before and after this moment. If the amplitude of voltage and current does not change for a period of time, then this section of data will not be stored.

[0046] The specific data screening method includes the control system continuously sliding cache analog data, and the cache window time Δt must be recorded before it is greater than or equal to the threshold. 1 (The time Δt needs to be recorded before the threshold 2 ), when the threshold trigger condition is met, the relevant cache data of the corresponding length will be formally recorded and saved, otherwise the cache data can be overwritten in a first-in-first-out manner. In this way, useful information can be recorded and stored while saving storage space.

[0047] Preferably, the measuring points mainly include the source of vehicle control instructions and / or the terminal loads of all electrical branches, the source of the vehicle control instructions includes switches, buttons or remote instructions, etc., and the terminal loads of the electrical branches include the coils of relays or solenoid valves, etc.

[0048] Preferably, the sampling frequency of the information acquisition is greater than or equal to 200kHz, so that the factors that may cause failure can be accurately reproduced, the voltage sampling accuracy is better than 1V, and the current sampling accuracy is better than 10mA, otherwise the amplitude of the waveform change cannot be effectively identified.

[0049] The sampling rate of the system implemented by the method of the present invention is set to two levels during continuous sampling: 200kHz and 1MHz. Users can choose according to actual needs. The difference between the two is mainly price and calculation error. The calculation error of some parameters will be relatively large under the 200k sampling frequency, while 1M can meet the requirements of accurate calculation of all parameters, mainly reducing the calculation error of action time, such as overtravel time. Conventionally, 200 kHz acquisition can be used, and 1MHz encrypted acquisition can be used when abnormalities are found.

[0050] Preferably, the voltage acquisition needs to be one-to-one, that is, each terminal load corresponds to a voltage acquisition port; the current acquisition can be shared by multiple branches, that is, the change of the corresponding branch current is determined by the change of the voltage state and the current amplitude.

[0051] Preferably, the threshold trigger includes voltage collection when the rising edge amplitude is greater than or equal to 1 / 20 of the rated working voltage or the falling edge amplitude is less than or equal to 4 / 5 of the rated working voltage, and current collection when the rising edge amplitude is greater than or equal to 1 / 10 of the rated working current or the falling edge amplitude is less than or equal to 4 / 5 of the rated working current. In this embodiment, for the conventional control circuit of the rail train with a rated working voltage of 110V and a rated working current of 50mA, the threshold trigger is uniformly set to carry out voltage collection when the rising edge amplitude is greater than or equal to 20V or the falling edge amplitude is less than or equal to 80V, and carry out current collection when the rising edge amplitude is greater than or equal to 10mA or the falling edge amplitude is less than or equal to 40mA; the period of time includes 50ms before the threshold and 50ms after the threshold. This is just a general sampling time setting. Of course, the data recording time before and after the threshold can also be determined according to the contact action delay characteristics, and the relevant data can even be recorded and stored directly from the corresponding moment of the threshold.

[0052] Preferably, in fact, even if only transient data is recorded, the total data of multiple branches is at a massive level. Therefore, the data screening also includes taking a single channel as the processing object, and counting the data of its trend changes over time; and taking the control timing when the vehicle is running as the processing object, and counting the data of the trend changes of multiple channels at a certain moment or a certain period of time. It should be noted that: the current acquisition port generally has multiple circuits sharing one current sensor, so it is necessary to combine the state change of the voltage channel to correspond to the current change. Thereby providing a reference benchmark of different dimensions for studying failure laws. This method can also be regarded as a data preprocessing method.

[0053] The channel change trend refers to the waveform of voltage and current. For example, a relay has 4 pairs of contacts, which drive 4 electrical branches respectively. When the coil of this relay is energized or de-energized, there should be 5 channels (4 contact channels + coil channel) that change. These channels have different load powers, and the voltage and current change trends of the circuits where the contacts are located are not the same. Therefore, taking the energization of this relay as an example, assuming that the energization means that the driver presses the button to issue a door opening command, then the 4 groups of contacts are used to execute TCMS to collect the closed state for recording, ATO to collect the closed state for sending the platform door opening command, and the remaining two groups of contacts drive some door controllers to control different functions such as door opening. From the actual working conditions of the vehicle, when the door opening command is issued, some functions (such as traction and door closing) will definitely not work, while other functions (such as power supply, air conditioning, lighting, braking) will definitely remain the same. Therefore, from the data of all channels, only the 5 channels corresponding to this relay have changed their states during this period of time. When it is necessary to analyze the changing rules of the characteristics of the door opening related circuits in the future, the channel data that has changed within this time range can be taken as a data packet, which can greatly improve the efficiency of data screening and eliminate the need to analyze each channel one by one. If it is found that the trend of a certain channel is quite different from the historical data or the data of other carriages when analyzing the data, then it can be determined that there is an abnormality in this channel. As for the judgment criteria, it is necessary to conduct state statistics in the early stage and screen the reasonable range of normal states. This work is a process of continuous analysis, optimization, and verification, and manual analysis can be used to improve accuracy. For example: after the coil is energized, if the contact closure time exceeds 20ms, it means that there is an abnormality in this contact. This criterion is a relatively simple threshold judgment.

[0054] Embodiment 2: The difference from Example 1 is that the sampling rate of this embodiment is directly set to 1 MHz, and is stored at 200 kHz when there is no obvious abnormality, otherwise it is stored at the original sampling rate.

[0055] Embodiment 3: The difference from Example 1 is that, for a DC drive with a rated voltage of DC24V and a rated current of 100mA, the threshold trigger includes voltage collection when the rising edge amplitude is greater than or equal to 1.2V or the falling edge amplitude is less than or equal to 18V, and current collection when the rising edge amplitude is greater than or equal to 10mA or the falling edge amplitude is less than or equal to 80mA.

[0056] Embodiment 4: A rail vehicle control loop online information collection system, according to embodiments 1 to 3 and any preferred embodiment, a system constituted by any one of the rail vehicle control loop online information collection methods described in any one of the preferred embodiments, comprises an information collection device and a control processing device.

[0057] Embodiment 5: A rail vehicle control loop failure warning method, for any system capable of acquiring time-varying information of a rail vehicle control loop current and / or voltage, in particular for the above-mentioned rail vehicle control loop online information acquisition system, is characterized in that the failure warning method includes a self-comparison judgment method of the own vehicle or a mutual comparison judgment method of different vehicles: The vehicle self-comparison judgment method includes taking the data of a certain electrical branch of the vehicle as a benchmark, comparing and analyzing the change trends under different seasons and different mileages, and identifying the mutation points under the same working conditions (such as similar time periods and the same functional operations); As mentioned above, the characteristics of the specific circuits of the existing vehicles are stable, including cables, connectors, loads, etc. According to operational experience, there may be certain differences in different seasons, but as long as the four seasons are observed throughout the year, the approximate range of characteristic drift can be basically determined. If the voltage or current amplitude is suddenly found to exceed this range (such as more than twice) during operation, this is a mutation and can be identified as a hidden danger. At this time, it can be further located through more sophisticated means (such as: increasing the sampling frequency to 1M, adding additional sensors for mutual comparison, etc., which depends on the characteristics of different circuits, branches, and channels, but the basic principles and methods remain unchanged).

[0058] The method of comparing different vehicles includes taking the data of different trains and the same loop as a benchmark, comparing the change trends under the same working conditions or within the same day, and identifying the differences therein. The difference point judgment can be the same as the mutation point judgment method; the different vehicles generally refer to different trains of the same batch.

[0059] For the same batch of trains, the characteristics of the same circuit are basically the same. The range of the four seasons can be counted as the evaluation standard, and then a margin of twice the range (adjustable) can be set to basically identify mutations. As long as there is a mutation, it can be considered a hidden danger, and then a more powerful means can be used for detailed investigation. It can be understood that the role of the diagnostic device is to give early warning, and the basic principle is to rather kill by mistake than let it go.

[0060] Since the components of the rail vehicle control loop include different devices of various types and models, and the circuit characteristics cannot remain consistent with changes in operating time and surrounding environment, it is impossible to set a unified threshold or model to achieve failure prediction.

[0061] The present invention takes a single electrical branch as the evaluation object, conducts comparative analysis from the above two aspects, summarizes the characteristic change trend of the rail vehicle control circuit, and then determines the threshold value, change rate and other evaluation criteria under different working conditions, so as to identify failure hazards in advance and issue failure warnings.

[0062] It should be noted that the threshold, change rate and other parameter settings described in the present invention can be used to screen data and improve the efficiency of alarms, but the determination of specific indicators needs to be combined with actual working conditions for statistics, analysis and screening. This work can be done manually or by self-learning algorithms. Generally speaking, as long as the data of the four seasons can be summarized, the evaluation indicators can be determined, and they can be continuously improved later.

[0063] Preferably, the failure warning determines the state change of each electrical branch and the principle of the cause of the state change, including any of the following items: ① Uniqueness principle: at any moment, only one functional state combination meets the design requirements; The control circuit of each train has about hundreds of relays, dozens of switch buttons, and a large number of metal contact components such as travel switches or pressure switches, which correspond to different functions such as power supply, traction, braking, door opening and closing, lighting, etc. From the perspective of the entire vehicle, at a certain moment, all functions can only be combined in one way, such as: when traction is effective, braking and door opening and closing must be invalid; whether it is stationary or running, power supply and lighting must always be effective. In other words, at any moment, all functions can only have one state, and this state is realized one by one according to the time sequence according to the needs of vehicle operation.

[0064] ② Association principle: Any state combination is determined by the previous state combination, that is, all circuits operate in sequence; For example, when the vehicle is operating with passengers, the realization of any function must have a trigger instruction, that is, a certain circuit must be powered on or off manually or remotely. In addition, there are many logical interlocking functions to ensure safety, such as overcurrent protection, mutual exclusion interlocking, etc. From the triggering of the instruction to the final execution, it is necessary to go through multiple circuits and multiple relays to complete the function. For example, when the door opening instruction is issued to open the door, it needs to go through the joint action of multiple links such as buttons, through wires, relays, travel switches, motors, and screws, and the actions of each link are in accordance with the set timing (that is, the relays are powered on and off in sequence). Therefore, Article 1 and Article 2 are a whole. As long as any principle is not met, it means that there is an abnormality.

[0065] ③ Duration parameter judgment principle: For channels that meet the above-mentioned uniqueness principle and association principle, it means that the timing control of each electrical branch is normal, and then it is necessary to screen whether there are abnormalities in parameters such as the action duration, and locate the abnormal components according to the correspondence between each channel and the actual vehicle circuit (such as: a group of contacts of a relay is sticky); for channels that do not meet the above principles, it means that there are occasional factors such as interference and poor contact, and it is necessary to focus on checking the connection status of the corresponding electrical branch.

[0066] If the action sequence of each circuit is normal, it means that the circuit has not had any faults that affect its function, but degradation cannot be ruled out. At this time, the corresponding state change duration judgment method is to pay attention to the change trend or threshold of the electrical parameters. For example: the time difference between the moment the coil is energized and the moment the contact is closed, thereby judging whether there is a jam; the time difference between the moment the coil is de-energized and the moment the contact is disconnected, thereby judging whether there is adhesion; observe whether the amplitude of the reverse electromotive force of the coil exceeds the standard, thereby judging whether there is a hidden danger of arcing, etc.

[0067] The abnormal positioning element can refer to the aforementioned measurement point arrangement and the design principles of related instructions (such as door opening and closing instructions). Viewing the electrical schematic diagram can guide the correspondence between each channel and the relay. When it is found that the waveform of a certain channel is greatly different from the normal value, the waveform of the associated channel corresponding to the abnormal moment can be observed to locate which link caused the abnormality. For example, taking the door opening relay as an example, if the waveform disconnection time of a certain channel is found to exceed the limit when the door opening instruction is revoked, then the group of contacts of this relay can be located to have a potential adhesion hazard. The cause of this hidden danger may be that the load power of this contact is large and the action frequency is high. By viewing the historical data, the specific cause can be further analyzed and the next step of the troubleshooting plan can be guided.

[0068] Regarding "checking the connection status of the corresponding electrical branch", if only one channel is abnormal at a certain moment, or multiple channels with no functional relationship have abnormalities at the same time, it means that the abnormality is not caused by the relay acting according to the instruction. For example: the circuit is on and off due to poor connector contact, which is inconsistent with the normal contact jitter from the voltage waveform, and always occurs in a specific channel at different times, then the possibility of relay contacts can be ruled out, and the line connection can be checked. If multiple channels occur at the same time and the waveforms are similar, it can be basically determined that there is interference in the space that leads to erroneous collection.

[0069] Preferably, the failure warning includes warnings of contact adhesion, contact sticking, poor contact, poor insulation or solenoid valve failure, which are also called warnings of degradation characteristics.

[0070] All faults in rail vehicle control circuits are a process of quantitative change to qualitative change. The main causes of deterioration include: material transfer caused by arcing, grounding or series current caused by poor insulation, jitter caused by mechanical reasons, excessive contact resistance caused by insufficient contact pressure, etc.

[0071] The present invention mainly diagnoses the following degradation characteristics: ① Contact adhesion: When the contact is disconnected and the inductive load loses power, arcing will occur between the moving and static contacts, resulting in material transfer to form protrusions and pits. After gradual accumulation, the contact gap becomes smaller and finally develops into adhesion. The present invention identifies adhesion hazards through three types of parameters: one is the voltage and current trend during the load power loss process, including duration and amplitude fluctuations; the second is the time difference between the coil power loss and the contact disconnection; the third is the switching time of the normally open contact and the normally closed contact, which is applicable to single-pole double-throw and forced-guided contacts.

[0072] For a specific type of relay, within the allowable load power range, its action time has a specific range, for example, the contact action time when power is off does not exceed 10ms. Although different loads will affect the action time, it must also be within this range. Here is an example:

[0073] First, the load power corresponding to each contact of the existing vehicle is fixed, and the failure-related factors caused by individual characteristic differences can be ignored. Even considering normal wear, the voltage and current change trends collected by each channel are stable, including their duration and amplitude. Similarly, if a sudden change in the trend is found, for example, the normal action time is 5ms, but a 10ms waveform is suddenly found, or the number of current changes caused by arcing increases, it means that there is a risk of adhesion in the contacts of this circuit.

[0074] Second, the time difference between the coil and the contact disconnection is mainly for a certain type of relay. A unified threshold is set according to its specification (for example, if it is specified not to exceed 10ms, then it can be set to 20ms to avoid false triggering) to identify abnormalities.

[0075] Third, for single-pole double-throw or forced-guided contacts, NO and NC are linked by mechanical structures. The basic principle is the same as judging the time difference between the coil and the contact, but this method is more accurate and can eliminate the error caused by the difference in coil characteristics. The travel between NO and NC contacts is fixed. If the switching time changes, the reason is either an abnormal reset spring or adhesion. An abnormal reset spring will cause the contact to fail to close, so it is also easy to distinguish the adhesion risk. The judgment threshold can refer to the methods of Articles 1 and 2.

[0076] ② Contact sticking: Generally, it is caused by mechanical reasons that the electromagnetic force of the coil cannot overcome the mechanical force. The present invention determines the potential sticking hazard through the time difference between the coil state change and the contact state change.

[0077] Take the contactor as an example. Its contact stroke is much larger than that of the relay, and its mechanical structure is relatively complex, with fixed and guided structures. After the coil is energized, the electromagnetic force needs to drive the spring to move on the set path. If the mechanical part is misaligned or broken, the stroke will be offset when the contact is actuated, and the moving and static contacts will not be able to effectively contact. The contactor also has a reasonable range of action time, such as: the action time does not exceed 60ms. If the coil is energized and the voltage waveform is not received for more than 100ms, it means that there is a hidden danger of jamming.

[0078] ③Poor contact: Mainly for circuit connection components such as contacts, pins, and crimping terminals. Insufficient crimping force causes the resistance of the contact surface to increase or even loosen. Among them, the contact type includes switches, buttons, travel switches, relay contacts and other devices with spring reset structures. The present invention identifies the hidden dangers of poor contact through two parameters: one is to use the line voltage drop (excluding load) and line current to calculate the line resistance, which can identify the hidden dangers of more serious poor contact; the second is the fluctuation of the line voltage amplitude. If it is a single-channel voltage change, it means that it is not caused by sequential action according to the timing requirements, but is caused by poor contact. It can identify occasional poor contact in the early stage of degradation, such as NC contacts of buttons or travel switches.

[0079] The conductive surfaces of contacts, pins, and crimping terminals are all maintained by elastic force. In addition, the conductive surfaces are also affected by environmental factors such as temperature, humidity, and salt spray to form an oxide film. The results of these factors will cause the contact resistance of the conductive surface to increase, and in severe cases, the voltage of the load coil will be insufficient to attract the contacts. Therefore, in the early stage of deterioration, the voltage difference between the positive pole of the power supply and the positive pole of the load is monitored, and then combined with the loop current, the line resistance other than the load can be calculated. The resistance of the cable is related to the length, which is a stable parameter and can be ignored. Therefore, as long as the calculated resistance is large, such as: more than 1Ω, it can be identified as poor contact. However, considering the recognition accuracy, this method may not necessarily identify all hidden dangers. The continued development of degradation will cause the voltage obtained by the load coil to become smaller and smaller. When its voltage is not enough to maintain the contact attraction, for example, the contact is on and off or the coil voltage fluctuates, the hidden danger of poor crimping can also be identified.

[0080] ④ Poor insulation: Poor insulation is a steady-state, gradual phenomenon, which mainly includes short circuit between coil turns, cross-circuit due to cable damage, cross-circuit due to water ingress to connectors, etc. The present invention identifies the hidden dangers of poor insulation through the current change trend of each channel.

[0081] As mentioned above, the characteristics of the current vehicle circuit are relatively stable. Even if they vary with the season and mileage, the variation is not large, and the trains in the same batch are basically consistent, so the current of each circuit is basically stable. Poor insulation can cause large fluctuations in current, and severe cases can cause short circuits. Therefore, by combining the current value under normal working conditions and setting a threshold error margin on this basis, poor insulation can be identified. For example: the rated current of a coil is 30mA, and the actual measured value of the current vehicle is 28mA. If the current of this channel is found to exceed 50mA one day, it can be identified as a hidden danger of poor insulation.

[0082] ⑤ Solenoid valve failure: Solenoid valve failure is manifested as air leakage, sticking and other air path control failures. The present invention identifies the hidden dangers of solenoid valve failure through the pressure change of the pressure sensor.

[0083] For example, if the solenoid valve coil loses power but there is still residual pressure in the pipeline, it means that the solenoid valve is leaking; or, if the solenoid valve is energized but the rate of increase of air pressure in the pipeline is much lower than normal working conditions (such as: under normal circumstances the pressure rise cannot exceed 3s, but the actual measurement is 5s), it means that the solenoid valve is leaking or stuck.

[0084] The basic principle of the present invention is: (1) Information acquisition method and system: The voltage and current are collected by using a high sampling frequency and high-precision analog acquisition port. This can not only accurately reproduce the waveform changes when the circuit is turned on and off according to instructions, but also collect occasional fluctuations during the circuit stabilization process. Only the rising edge and / or falling edge are sampled and recorded, which greatly saves storage space and improves judgment efficiency.

[0085] (2) Measurement point selection: The branch is taken as the research object, and the terminal load of each electrical branch is the collection object. Any change in this branch will cause changes in the terminal load voltage and current, thereby realizing the online status collection of each branch. Real-time record of circuit characteristic changes under the current vehicle operating conditions, especially fluctuations caused by accidental factors.

[0086] (3) Prediction algorithm: Based on the online status changes of each branch and the circuit characteristics of each electrical branch, the abnormal circuit status is identified by setting thresholds, judging trends and other comparison methods, and potential failure hazards are screened in advance to avoid failures caused by the gradual accumulation of degradation.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, without departing from the technical principles of the present invention, several improvements and modifications can be made, such as redundant arrangement of measuring points, change of data screening range, and establishment of complete failure prediction logic based on the principles and methods of the present invention, etc. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for collecting online information of a rail vehicle control loop, characterized in that: The collection method comprises: S1. Measurement point arrangement: the electrical circuit is used as the information collection unit, and at least one measurement point is designed for each branch of the circuit; S2, information collection, the information collection includes analog voltage collection and / or analog current collection, and the collection method includes timed collection at each measuring point and / or rotation collection; S3, data screening, including recording and storing the analog rising edge and / or falling edge data, recording and storing the analog data for a period of time before and after the threshold in a threshold triggering manner; the rising edge includes the moment when the coil is energized, and the falling edge includes the moment when the coil is de-energized.

2. The method for collecting online information of a rail vehicle control loop according to claim 1, characterized in that: The measuring point includes a source of a vehicle control command and / or a terminal load of an electrical branch circuit. The source of the vehicle control command includes a switch, a button or a remote command. The terminal load of the electrical branch circuit includes a coil of a relay or a coil of a solenoid valve.

3. The method for collecting online information of a rail vehicle control loop according to claim 1, characterized in that: The sampling frequency of the information collection is greater than or equal to 200kHz, the voltage sampling accuracy is better than 1V, and the current sampling accuracy is better than 10mA.

4. The method for collecting online information of a rail vehicle control loop according to claim 1, characterized in that: The voltage acquisition requires that each terminal load corresponds to a voltage acquisition port.

5. The method for collecting online information of a rail vehicle control loop according to claim 1, characterized in that: The threshold trigger includes voltage collection when the rising edge amplitude is greater than or equal to 1 / 20 of the rated working voltage or the falling edge amplitude is less than or equal to 4 / 5 of the rated working voltage, and current collection when the rising edge amplitude is greater than or equal to 1 / 10 of the rated working current or the falling edge amplitude is less than or equal to 4 / 5 of the rated working current; the period of time is less than or equal to the continuous change time from the minimum value to the maximum value or from the maximum value to the minimum value.

6. The method for collecting online information of a rail vehicle control loop according to claim 1, characterized in that: The data screening also includes taking a single channel as a processing object and counting the data of its trend changes over time; and taking the control timing when the vehicle is running as a processing object and counting the data of the trend changes of multiple channels at a certain moment or within a certain period of time.

7. A rail vehicle control loop online information acquisition system, characterized in that: The system constituted by the rail vehicle control loop online information collection method according to any one of claims 1 to 6 comprises an information collection device and a control processing device.

8. A rail vehicle control loop failure early warning method, for any system capable of obtaining time-varying information of rail vehicle control loop current and / or voltage, characterized in that: The failure warning method includes a self-comparison judgment method of the vehicle or a mutual comparison judgment method of different vehicles: The vehicle self-comparison judgment method includes taking the data of a certain electrical branch of the vehicle as a benchmark, comparing and analyzing the change trends under different seasons and different mileages, and identifying the mutation points therein; The method for comparing different trains includes taking data of different trains and the same loop as a benchmark, comparing the change trends under the same working conditions or within the same day, and identifying the differences therein.

9. The rail vehicle control circuit failure early warning method according to claim 8, characterized in that: The principles for failure warning judgment include any of the following: ① Uniqueness principle: at any moment, only one functional state combination meets the design requirements; ② Association principle: Any state combination is determined by the previous state combination, that is, all circuits operate in sequence; ③ Duration parameter judgment principle: For channels that meet the above-mentioned uniqueness principle and association principle, it means that the timing control of each electrical branch is normal. Then it is necessary to screen whether there are any abnormalities in its action duration parameters, and locate the abnormal components according to the correspondence between each channel and the existing vehicle circuit.

10. The rail vehicle control circuit failure early warning method according to claim 8, characterized in that: The failure warning includes a warning of contact adhesion, contact sticking, poor contact, poor insulation or solenoid valve failure.

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