A kind of line-break resonance diagnosis device and diagnosis method

Abstract

This invention provides a device and method for diagnosing open-circuit resonance, comprising: a coprocessor, a load switch, a carrier generator, a unidirectional coupler, a DC detector, a DC demodulator, a resonant detector, and a high-frequency demodulator; the coprocessor is connected to the load switch, the carrier generator, the DC detector, and the resonant detector respectively, and is used to operate the load switch to output a load signal, operate the carrier generator to generate a frequency-adjustable modulated carrier signal, and diagnose the measurement signals of the DC detector and the resonant detector respectively to obtain diagnostic results, and confirm the open-circuit location based on the diagnostic results; the unidirectional coupler is connected to the load switch and the carrier generator respectively, and is used to load the modulated carrier signal generated by the carrier generator into the output signal of the load switch to obtain a modulated load signal; the DC demodulator is connected to the DC detector.

Description

Technical Field

[0001] The invention belongs to the technical field of industrial electronics, and in particular relates to a disconnection resonance diagnosis device and a diagnosis method. Background Art

[0002] I / O, the full name of Input / Output Interface, refers to the input / output device interface in a computer control system. It is the most common physical layer medium for information exchange between the host and external devices in a computer control system.

[0003] Similarly, in industrial sites, I / O interfaces are also the most common physical medium for information exchange between "host devices" such as PLCs and distributed I / O modules and "external devices" such as stoppers, indicator lights, frequency converters and sensors. According to rough statistics, in my country's automated industrial sites, an average of 10-25 I / O interfaces and 10-25 meters of I / O transmission cables are distributed in an area of ​​only one square meter, of which DI / DO accounts for as much as 87%. As the interface form with the highest distribution density in industrial sites, DI / DO has many advantages such as simple logic, easy operation, low cost, high anti-interference, low signal attenuation during long-distance transmission, and no need for error control and data verification. It is widely used in a large number of electrical equipment and provides important guarantees for efficient, safe and reliable production in industrial sites at all times.

[0004] However, in actual application scenarios, due to the widespread use of DI / DO interfaces, it has also become one of the most common fault interfaces in industrial sites. In some industrial scenarios, due to the cost constraints when deploying electrical systems, cables of poor quality are selected to transmit DI / DO signals. Such cables are extremely susceptible to oil pollution in industrial environments, causing rust and accelerated oxidation, etc., which causes the resistivity of the cables in the rusted or oxidized areas to increase abnormally, and ultimately causes performance abnormalities or functional failures in the electrical system; in some engineering machinery or moving electromechanical equipment in industrial scenarios, the cables inside the moving parts are often subjected to torsion, shear or tension generated by mechanical movement, resulting in wire core aging. This aging phenomenon will also cause the resistivity of a certain area of ​​the cable to increase abnormally, and even be equivalent to a circuit break; or some electrical equipment in the electrical system itself has aged, resulting in abnormal conditions on the DI / DO signal line.

[0005] When such faults occur, maintenance personnel are often required to inspect, locate, analyze and eliminate the faults. However, in modern industrial sites composed of large-scale production equipment, the length of DI / DO cables is often tens of meters or even hundreds of meters. In such a long cable distribution state, it is particularly difficult to find the cable breakpoint. In addition, in some industrial sites, DI / DO cables, PLCs or certain terminal devices are deployed in difficult operating environments, such as ionizing radiation radioactive environments, confined space environments, underwater environments, high-altitude environments or toxic chemical gas environments. Maintenance personnel need to spend a lot of time on site to inspect, locate and analyze faults, rather than directly adjusting and repairing the fault points. This makes maintenance operations more limited, complex and dangerous.

[0006] In response to the above problems, there are many devices and instruments that can be used for disconnection detection in the market at this stage, and there are also some diagnostic devices for DI / DO interfaces, but they all have defects such as "inability to detect online", "inability to identify cable DI / DO faults and terminal equipment faults", "inability to infer the location of the disconnection point" and "difficult to deploy", which makes the prospects of these devices and instruments being promoted to industrial sites very poor.

[0007] Example 1, the invention patent with application number 202311782415.4 discloses "line break detection circuit, electronic device and line break detection system", which aims to reduce the cost of line break detection circuit. It can be used to connect and disconnect the line to be detected that is connected to the circuit to be detected, and the circuit structure is simple and easy to implement. However, when some terminal equipment itself fails, the invention is easily mistaken for the connection and disconnection of the line to be detected, thereby leading the maintenance personnel's work direction into a misunderstanding. Moreover, even if the occurrence of a line break anomaly is accurately detected, it is impossible to deduce the possible location of the line break point, and the maintenance personnel still need to spend a lot of energy to check the location of the break point. It can be seen from this that even if the invention realizes a certain line break detection function, it has almost no promotion value in actual applications.

[0008] Example 2, the invention patent "A wire break detection system" with application number 202310139839.2 discloses a wire break detection device consisting of a current limiting resistor, an optocoupler, an anti-interference and impedance conversion module and an MCU. Compared with Example 1, there is still a defect that when some terminal devices themselves fail, the invention is easily mistaken for the on / off of the line to be detected. In addition, this invention patent can only be used in AC control loops. Even if its detection range is further expanded, it cannot be used for wire break detection in DC control loops. However, for most industrial sites at home and abroad at this stage, the utilization rate of DC 24V control loops is much higher than that of church control loops. Obviously, this invention still has many limitations in actual promotion.

[0009] Example 3, the invention patent "A disconnection detection circuit and chip" with application number 202310772449.9 discloses a disconnection detection device composed of multiple batteries, multiple resistors and other components. Due to the characteristic that its measurement circuit does not pass through the terminal device, it overcomes the problem of misjudgment in Example 1 and Example 2. However, this also makes the invention patent unable to be used online, that is, when detecting the on and off of the line, the line to be detected must be disconnected from the terminal device and connected to the invention, and the invention still cannot calculate the breakpoint position. Such usage and functional characteristics have hardly improved the complexity and difficulty of maintenance work, and it still does not have a high promotion value.

[0010] Example 4, the invention patent with application number 202210853021.2 is "A cable breakpoint positioning detection device and method". This invention patent discloses a wire break detection device consisting of an equidistant parallel equivalent resistance circuit and a monitor. This device has a great technical progress compared with Examples 1, 2 and 3. From a functional analysis, this invention patent overcomes the problem of misjudgment in Examples 1 and 2, and also overcomes the problem of being unable to be used online in Example 3, while also realizing a more accurate breakpoint position calculation function. However, according to the description of the invention, "the equidistant parallel equivalent resistance circuit is composed of resistors of the same resistance value connected in parallel at the same spacing and wrapped around the outer periphery of the cable". Using this method to achieve the wire break detection function is bound to greatly increase the workload, deployment difficulty and cost during the deployment of the electrical system. Taking all factors into consideration, the invention can be further studied and optimized as a "conceptual technology", but for practical applications at this stage, the invention basically has no possibility of being widely promoted and used.

[0011] Obviously, the diagnostic equipment for DI / DO interfaces currently available in the market based on existing technologies have defects such as "inability to detect online", "inability to identify cable DI / DO faults and terminal equipment faults", "inability to infer the location of the disconnection point", and difficulty in deployment, which makes them difficult to promote. Therefore, if we want to conduct convenient, efficient, real-time and safe diagnosis of DI / DO interfaces in modern industrial sites, we must start to develop diagnostic equipment based on new technologies. Summary of the invention

[0012] The present invention provides a line break resonance diagnosis device and a diagnosis method, which can at least solve the problems of "inability to detect online", "inability to identify cable DI / DO faults and terminal equipment faults", "inability to infer the location of the line break point" and high deployment difficulty.

[0013] The technical solution provided by the present invention is as follows:

[0014] In one aspect, a disconnection resonance diagnostic device is provided, comprising: a coprocessor, a load switch, a carrier generator, a unidirectional coupler, a DC detector, a DC demodulator, a resonance detector, and a high-frequency demodulator;

[0015] The coprocessor is connected to the load switch, the carrier generator, the DC detector and the resonance detector respectively, and is used to operate the load switch to output a load signal, and to operate the carrier generator to generate a modulated carrier signal with an adjustable frequency, and to diagnose the measurement signals of the DC detector and the resonance detector respectively to obtain a diagnosis result, and to confirm the disconnection position based on the diagnosis result;

[0016] The one-way coupler is connected to the load switch and the carrier generator respectively, and the one-way coupler is used to load the modulated carrier signal generated by the carrier generator into the output signal of the load switch to obtain a modulated load signal;

[0017] The DC demodulator is connected to a DC detector, and is used to demodulate a DC signal from the modulated load signal and transmit the DC signal to the DC detector for detection by the DC detector;

[0018] The high frequency demodulator is connected to the resonance detector, and is used for demodulating the modulated carrier from the modulated load signal and transmitting the modulated carrier to the resonance detector for detection by the resonance detector.

[0019] In an optional implementation, the disconnection resonance diagnostic device includes a first port and a second port;

[0020] The first port is used to connect to an external host processor communication bus; and

[0021] The second port is used to connect to an output cable.

[0022] In an optional implementation, the frequency of the modulated carrier generated by the coprocessor is in the range of 1.50 MHz to 60.00 MHz.

[0023] On the other hand, a method for diagnosing a broken line resonance is provided, the method comprising any one of the above-mentioned broken line resonance diagnosis devices for diagnosis, the method comprising:

[0024] Get real-time resonant voltage amplitude Relative to the initial resonant voltage amplitude The first change result;

[0025] Get the initial disconnection DC component amplitude Relative to the real-time disconnection DC component amplitude The second change result;

[0026] Get the initial closed DC component amplitude Relative to the real-time closed DC component amplitude The third change result of ; and

[0027] The disconnection position is determined and confirmed based on the first change result, the second change result and the third change result.

[0028] In an optional implementation, the real-time resonant voltage amplitude is obtained Relative to the initial resonant voltage amplitude The first changes result in:

[0029] Obtain the highest frequency point of the resonant voltage amplitude of the modulated carrier signal generated by the carrier generator when the load switch is disconnected for the first time, and use the highest frequency point of the resonant voltage amplitude as the initial resonant frequency point ;

[0030] Get the current resonant voltage amplitude as the initial resonant voltage amplitude ;

[0031] Each time the load switch is disconnected thereafter, the initial resonant frequency Transmitting a modulated carrier signal to an output cable and measuring a resonance voltage amplitude, and taking the resonance voltage amplitude as a real-time resonance voltage amplitude U; and

[0032] Based on the real-time resonant voltage amplitude Relative to the initial resonant voltage amplitude The first change result is obtained by the change of

[0033] In an optional implementation, the initial disconnection DC component amplitude is obtained Relative to the real-time disconnection DC component amplitude The second change results include:

[0034] Obtain the DC component in the output cable when the load switch disconnection operation is performed for the first time, and use the DC component as the initial disconnection DC component amplitude ;

[0035] Each time the load switch is disconnected, the DC component in the output cable is obtained and the amplitude of the DC component is disconnected in real time. ;as well as

[0036] Based on the initial disconnection DC component amplitude Relative to the real-time disconnection DC component amplitude The second change result is obtained by the change of

[0037] In an optional implementation, the initial closed DC component amplitude is obtained to determine Relative to the real-time closed DC component amplitude The third change results include:

[0038] Get the DC component in the output cable when the load switch is closed for the first time, and use it as the initial closed DC component amplitude ;

[0039] Each time the load switch is closed, the DC component in the output cable is measured as the real-time DC component amplitude. ;as well as

[0040] Based on the initial closed DC component amplitude Relative to the real-time closed DC component amplitude The third change is performed to obtain the third change result.

[0041] In an optional implementation, the method further includes: obtaining a minimum length and a maximum length of an output cable when transmitting a modulated carrier signal within a range of 0.30 MHz to 60.00 MHz;

[0042] An output cable capable of forming an antenna effect when transmitting a modulated carrier signal within a range of 0.30 MHz to 60.00 MHz is determined based on the minimum length and the maximum length of the output cable.

[0043] In an optional implementation, when the disconnection position is the output cable, the disconnection resonance diagnosis device readjusts the resonance to obtain a new resonance frequency point as the real-time resonance frequency point when the disconnection position is the output cable;

[0044] Obtaining the output lengths between all possible breakpoints of the output cable and the break resonance diagnostic device, recorded as a breakpoint distance set L; and

[0045] The breakpoint position is determined based on the breakpoint distance set L.

[0046] In an optional implementation, determining the breakpoint position based on the breakpoint distance set L includes: determining the breakpoint position based on the following formula:

[0047]

[0048]

[0049] in, represents the breakpoint distance set, is the wavelength of the modulated carrier signal.

[0050] The disconnection resonance diagnosis device provided by the embodiment of the present invention has at least the following beneficial effects:

[0051] In the embodiment of the present invention, when the disconnection resonance diagnosis device performs a disconnection operation, disconnection detection based on the resonance principle is performed. The detection signal is a radio frequency domain signal with high frequency and low amplitude, so it will not have any adverse effects on the terminal equipment connected to the output cable. The present invention adopts the resonance detection principle to detect disconnection of the output cable, which can reduce all the abnormal misjudgments of disconnection caused by terminal equipment failure under the defects of traditional technology, and greatly avoids the unnecessary workload brought to the maintenance personnel by the erroneous judgment information provided by the diagnostic system. The present invention is applied to the output circuit interface design of PLC or distributed I / O modules, and there is no need to destroy the terminal equipment when using it. The on-site electrical environment can realize real online diagnosis, which brings great convenience and safety to maintenance work; after detecting the possible or existing abnormal disconnection, the present invention uses re-tuning to infer the possible disconnection point position, which also provides great convenience for the repair work after the output cable is disconnected, and greatly reduces the downtime caused by the repair work after the output cable is disconnected in the industrial site; when the disconnection resonance diagnosis device performs the disconnection and closing operations, the DC component amplitude in the output cable is measured and diagnosed respectively, and combined with the disconnection detection based on the resonance principle, the possible or existing terminal equipment failure can be determined. In particular, this method can identify the situation where most terminal equipment is aged but no functional abnormality occurs (the aging of the terminal equipment is generally reflected in the abnormal change of the input resistance of the interface connected to the output cable, and the problem can be identified by analyzing the DC component amplitude in the output cable), so as to warn the maintenance personnel as early as possible and prompt potential fault hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components in the exemplary embodiments of the present disclosure.

[0053] Figure 1 It is a circuit principle block diagram of the present invention.

[0054] Figure 2 It is a schematic flow chart of the disconnection resonance diagnosis method of the present invention.

[0055] Figure 3 FIG. 1 is a flow chart of step S101 of the disconnection resonance diagnosis method of the present invention.

[0056] Figure 4 FIG. 1 is a flow chart of step S102 of the disconnection resonance diagnosis method of the present invention.

[0057] Figure 5FIG. 1 is a flow chart of step S103 of the disconnection resonance diagnosis method of the present invention.

[0058] Figure 6 This is a block diagram of a typical application circuit of the present invention.

[0059] Figure 7 Schematic diagram of the operation structure of the automatic painting production line in the embodiment.

[0060] Figure 8 This is a topological diagram of the control system of the automated painting production line before transformation in the embodiment.

[0061] Fig. 9 It is a block diagram of the circuit principle of the distributed I / O module in the prior art in the embodiment.

[0062] Fig.10 This is a topological diagram of the control system of the automated painting production line after transformation in the embodiment. DETAILED DESCRIPTION

[0063] The embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0064] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0065] See also Figure 1 The embodiment of the present invention provides a disconnection resonance diagnosis device, including: a coprocessor, a load switch, a carrier generator, a unidirectional coupler, a DC detector, a DC demodulator, a resonance detector and a high-frequency demodulator.

[0066] The coprocessor is connected to the load switch, carrier generator, DC detector and resonance detector respectively. The coprocessor is used to operate the load switch to output a load signal, and to operate the carrier generator to generate a modulated carrier signal with adjustable frequency, and to diagnose the measurement signals of the DC detector and the resonance detector respectively to obtain diagnosis results, and to confirm the disconnection position based on the diagnosis results.

[0067] The unidirectional coupler is connected to the load switch and the carrier generator respectively. The unidirectional coupler is used to load the modulated carrier signal generated by the carrier generator into the output signal of the load switch to obtain a modulated load signal.

[0068] The DC demodulator is connected to the DC detector, and is used for demodulating a DC signal from a modulated load signal and transmitting the DC signal to the DC detector for detection by the DC detector.

[0069] The high frequency demodulator is connected to the resonant detector, and is used for demodulating the modulated carrier from the modulated load signal and transmitting the modulated carrier to the resonant detector for detection.

[0070] In an optional implementation, the line break resonance diagnostic device includes a first port and a second port; the first port is used to connect to an external host processor communication bus; and the second port is used to connect to an output cable.

[0071] The broken line resonance diagnosis device provided by the embodiment of the present invention is a dual-port network. In practical application, the first port is used to connect to an external host processor communication bus; and the second port is used to connect to an output cable.

[0072] In an optional implementation, the frequency of the modulated carrier generated by the coprocessor is in the range of 1.50 MHz to 60.00 MHz.

[0073] See also Figure 2 On the other hand, a method for diagnosing a broken line resonance is provided, the method comprising using any of the above-mentioned broken line resonance diagnostic devices for diagnosis, the method comprising: step S101, step S102, step S103 and step S104.

[0074] Step S101: Obtaining real-time resonant voltage amplitude Relative to the initial resonant voltage amplitude The first change result.

[0075] Step S102: Obtaining the initial disconnection DC component amplitude Relative to the real-time disconnection DC component amplitude The second change result.

[0076] Step S103: Obtain and determine the initial closed DC component amplitude Relative to the real-time closed DC component amplitude The third change result.

[0077] Step S104: determine and confirm the disconnection position based on the first change result, the second change result, and the third change result.

[0078] The disconnection resonance diagnosis device provided in the embodiment of the present invention transmits a modulated carrier to the output cable and tunes the modulated carrier by using interval frequency sweeping and resonance detection when performing a disconnection operation, thereby confirming the optimal resonant frequency of the output cable. Each time the disconnection resonance diagnosis device performs a disconnection operation thereafter, the tuning and confirmation of the resonant frequency are repeated, and the abnormal change of the resonant frequency is judged to determine whether the output cable may be disconnected.

[0079] In an optional embodiment, it also includes: obtaining the minimum length and maximum length of the output cable when the modulated carrier signal is transmitted in the range of 0.30MHz-60.00MHz; based on the minimum length and maximum length of the output cable, determining the output cable that can form an antenna effect when the modulated carrier signal is transmitted in the range of 0.30MHz-60.00MHz.

[0080] Furthermore, when the resonant frequency changes significantly, the new optimal resonant frequency is re-determined and converted into a wavelength; based on the antenna effect, "the antenna length corresponding to the optimal resonant frequency should be an integer multiple of 1 / 4 wavelength", the possible positions of all breakpoints can be calculated. Among them, the "antenna effect" refers to the fact that when the disconnection resonance diagnostic device performs the load switch disconnection operation for the first time after deployment, it transmits a modulated carrier signal to the output cable in a fast frequency sweeping manner with a range of 0.30MHz-60.00MHz and a step of 5KHz. At this time, the output cable can be regarded as a long-line antenna, forming an antenna effect.

[0081] On this basis, when the intelligent output interface unit of the disconnection resonance diagnosis device performs the disconnection and closing operations, the DC component amplitude in the output cable is measured respectively. And each time the intelligent output interface unit of the disconnection resonance diagnosis device performs the disconnection and closing operations thereafter, the DC component amplitude in the output cable is repeatedly measured, and by judging the abnormal change of the DC component amplitude and combining the judgment result of the resonance frequency, it is further judged whether the abnormality is caused by the disconnection of the output cable or the terminal device connected to the output cable.

[0082] The disconnection resonance diagnosis method of the present invention will be further explained and described below through optional embodiments.

[0083] See also Figure 3 In an optional implementation, step S101, obtaining the real-time resonant voltage amplitude Relative to the initial resonant voltage amplitude The first change result includes: step S1011, step S1012 and step S1013.

[0084] Step S1011, obtaining the highest frequency point of the resonant voltage amplitude of the modulated carrier signal generated by the carrier generator when the load switch disconnection operation is performed for the first time, and taking the highest frequency point of the resonant voltage amplitude as the initial resonant frequency point .

[0085] Step S1012: Obtain the current resonance voltage amplitude as the initial resonance voltage amplitude .

[0086] Each time the load switch is turned off, the initial resonant frequency A modulated carrier signal is transmitted to the output cable and the resonance voltage amplitude is measured, and the resonance voltage amplitude is used as the real-time resonance voltage amplitude U.

[0087] Step S1013: Based on the real-time resonant voltage amplitude Relative to the initial resonant voltage amplitude The change in obtains the first change result.

[0088] See also Figure 4 In an optional implementation, step S102, obtaining the initial disconnection DC component amplitude Relative to the real-time disconnection DC component amplitude The second change result includes: step S1021, step S1022 and step S1023.

[0089] Step S1021: Obtain the DC component in the output cable when the load switch disconnection operation is performed for the first time, and use the DC component as the initial disconnection DC component amplitude .

[0090] Step S1022: After each load switch disconnection operation is performed, the DC component in the output cable is obtained, and the amplitude of the DC component is disconnected in real time. ;as well as

[0091] Step S1023: based on the initial disconnection DC component amplitude Relative to the real-time disconnection DC component amplitude The change in obtains the second change result.

[0092] See also Figure 5 In an optional implementation, step S103, obtaining and determining the initial closed DC component amplitude Relative to the real-time closed DC component amplitude The third change result includes: step S1031, step S1032 and step S1033.

[0093] Step S1031: Obtain the DC component in the output cable when the load switch closing operation is performed for the first time, and use it as the initial closing DC component amplitude ;

[0094] Step S1032: Each time the load switch is closed, the DC component in the output cable is measured as the real-time closed DC component amplitude. ;as well as

[0095] Step S1033: Based on the initial closed DC component amplitude Relative to the real-time closed DC component amplitude The third change obtains the third change result.

[0096] In an optional implementation, step S104, determining and confirming the disconnection position based on the first change result, the second change result, and the third change result, includes the following steps:

[0097] 1. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude No obvious change, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude No significant change, initial closed DC component amplitude Compared with the real-time closed DC component amplitude There is no obvious change. Based on the maximum length of the output cable under the antenna effect, Lmax=λ / 4, it is obtained that under the restriction of the frequency range of 0.30MHz-60.00MHz, the maximum antenna length of the antenna effect is 250m, that is, the maximum adapted output cable length of 250m changes: the broken line resonance diagnostic device of the present invention prompts that there is no abnormality in the output cable, which means that there is no abnormality in the terminal equipment.

[0098] 2. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude No obvious change, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude No significant change, initial closed DC component amplitude Compared with the real-time closed DC component amplitude Obvious change.

[0099] This indicates that the input impedance of the terminal device may have changed, causing the initial closed DC component amplitude to Compared with the real-time closed DC component amplitude The disconnection resonance diagnostic device of the present invention prompts that there is no abnormality in the output cable, but the terminal device is abnormal.

[0100] 3. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude No obvious change, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude If the input impedance of the terminal device changes significantly, it may be that the DC component amplitude is disconnected in real time. Compared with the initial disconnection DC component amplitude The disconnection resonance diagnostic device of the present invention prompts that there is no abnormality in the output cable, but the terminal device is abnormal.

[0101] 4. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude No obvious change, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude Obviously changed, the initial closed DC component amplitude Compared with the real-time closed DC component amplitude If the input impedance of the terminal device changes significantly, it may be that the DC component amplitude is disconnected in real time. Compared with the initial disconnection DC component amplitude It is also possible that the output cable has been disconnected due to mechanical force, corrosion or oxidation, resulting in an increase in impedance, but the part of the output cable from the interface of the disconnection resonance diagnostic device to the failure point has formed a new antenna effect, and the new antenna effect corresponds to the effective length of the output cable at the initial resonant frequency. The corresponding wavelength is multiplied by an integer multiple of one quarter; the disconnection resonance diagnostic device of the present invention prompts that the output cable may be abnormal and the terminal device may be abnormal.

[0102] 5. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude Significant changes, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude No significant change, initial closed DC component amplitude Compared with the real-time closed DC component amplitude If there is no obvious change, it means that the output cable has been loosely connected due to mechanical force, rust or oxidation, resulting in increased impedance but not completely disconnected, and the original tuning state is destroyed; then the disconnection resonance diagnostic device of the present invention prompts that the DO cable is abnormal, but the terminal device is normal.

[0103] 6. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude Significant changes, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude If there is no obvious change, the initial closed DC component amplitude Compared with the real-time closed DC component amplitude An obvious change is that the output cable has been loosely connected, corroded or oxidized due to mechanical force, causing the impedance to increase but not completely disconnected, and the original tuning state has been destroyed.

[0104] 7. If the input impedance of the terminal device has changed, resulting in the initial closed DC component amplitude Compared with the real-time closed DC component amplitude The disconnection resonance diagnostic device of the present invention prompts that the output cable is abnormal and the terminal device is abnormal.

[0105] 8. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude Significant changes, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude Obviously changed, Initial closing DC component amplitude Compared with the real-time closed DC component amplitude If there is no obvious change, it means that the output cable has been loosely connected, corroded or oxidized due to mechanical force, causing the impedance to increase but not completely disconnected, and the original tuning state has been destroyed.

[0106] 9. If the input impedance of the terminal device has changed, causing the DC component amplitude to be disconnected in real time Compared with the initial disconnection DC component amplitude The disconnection resonance diagnostic device of the present invention prompts that the output cable is abnormal and the terminal device is abnormal.

[0107] 10. If the real-time resonant voltage amplitude Compared with the initial resonant voltage amplitude Significant changes, real-time disconnection of DC component amplitude Compared with the initial disconnection DC component amplitude Obviously changed, the initial closed DC component amplitude Compared with the real-time closed DC component amplitude If the output cable has changed significantly, it means that the output cable has been disconnected completely or partially due to mechanical force, corrosion or oxidation, resulting in increased impedance, and the original tuning state has been destroyed; it may also be that the input impedance of the terminal device has changed, resulting in real-time disconnection of the DC component amplitude. Compared with the initial disconnection DC component amplitude If the output cable is abnormal, the terminal device may be abnormal.

[0108] In other unspecified situations, the disconnection resonance diagnosis device of the present invention will prompt other unpredictable faults.

[0109] When the coprocessor determines that the output cable may be abnormal or has been abnormal, the disconnection resonance diagnostic device of the present invention can automatically re-tune to find a new resonance frequency point, which is recorded as the real-time resonance frequency point, and calculate the output cable length between all possible breakpoints and the disconnection resonance diagnostic device of the present invention, which is recorded as the breakpoint distance set L, and the set L is uploaded to the upper processor to assist in calculating the possible breakpoint position. The specific calculation method is as follows:

[0110] In an optional implementation, when the disconnection position is the output cable, the disconnection resonance diagnosis device readjusts the resonance to obtain a new resonance frequency point as the real-time resonance frequency point when the disconnection position is the output cable;

[0111] Obtaining the output lengths between all possible breakpoints of the output cable and the break resonance diagnostic device, recorded as a breakpoint distance set L; and

[0112] The breakpoint positions are determined based on the breakpoint distance set L.

[0113] In an optional implementation, determining the breakpoint position based on the breakpoint distance set L includes: determining the breakpoint position based on the following formula:

[0114]

[0115]

[0116] in, represents the breakpoint distance set, is the wavelength of the modulated carrier signal.

[0117] It should be noted that since the effective length of the output cable is 1 / 4 times the wavelength of the modulated carrier signal, the amplitude of the resonant voltage that produces the antenna effect is the highest, so the smaller n is, the more likely the breakpoint distance is to be calculated. The greater the probability of being correct.

[0118] In summary, the present invention performs disconnection detection based on the resonance principle when the disconnection resonance diagnostic device performs a disconnection operation. The detection signal is a radio frequency domain signal with high frequency and low amplitude, so it will not produce any adverse effects on the terminal equipment connected to the output cable.

[0119] The present invention adopts the resonance detection principle to detect the disconnection of the output cable, which can reduce all the abnormal misjudgments of disconnection caused by terminal equipment failure under the defects of traditional technology, and greatly avoids the unnecessary workload brought to the maintenance personnel by the erroneous judgment information provided by the diagnostic system.

[0120] The present invention is applied to the design of DO circuit interfaces such as PLC or distributed I / O modules. When used, there is no need to destroy the on-site electrical environment, and true online diagnosis can be achieved, which brings great convenience and safety to maintenance work.

[0121] After detecting a possible or already occurred abnormal disconnection, the present invention uses a re-tuning method to infer the possible disconnection point position, which also provides extremely high convenience for the repair work after the output cable is broken, and greatly reduces the production downtime caused by the repair work after the output cable is broken in the industrial site.

[0122] When the disconnection resonance diagnostic device performs the opening and closing operations, the DC component amplitude in the output cable is measured and diagnosed respectively, and combined with the disconnection detection based on the resonance principle, the possible or existing terminal equipment failure can be determined. In particular, this method can identify the situation where most terminal equipment is aged but no functional abnormality occurs (the aging of terminal equipment is generally reflected in the abnormal change of the input resistance of the interface connected to the DO cable, and this problem can be identified by analyzing the DC component amplitude in the DO cable), so as to warn the maintenance personnel as early as possible and indicate the potential fault hazards.

[0123] Example

[0124] In the automated production workshop of a domestic gear motor manufacturing company, there is an automated painting production line. The operating structure of the production line is shown in the following figure. Figure 7 shown.

[0125] The power source of the guide rail is the guide rail motor at the far end of the automated painting operation industry. The production line runs from left to right. After the previous process is completed, the reduction motor to be painted is hoisted by the sling running on the guide rail and enters the automated painting operation production line from the left. In order to keep the painting operation environment dust-free, the entrance dustproof roller shutter is normally closed. After the entrance sensor detects the reduction motor, the entrance dustproof roller shutter is rolled up and opened to allow the reduction motor to be painted to enter the core operation area. The temperature sensor and heater form a temperature feedback regulation system to control the air temperature in the core operation area within the range of +75.00℃±1.50℃.

[0126] The sling running on the guide rail drags the reduction motor to be painted to run continuously from left to right. When the paint sensor detects that the reduction motor to be painted is approaching, the entrance dustproof roller shutter falls down and closes, the paint nozzle is started, and the paint operation on the reduction motor to be painted begins; when the drying sensor detects that the reduction motor is approaching, the paint nozzle stops running, and the drying nozzle starts to dry the reduction motor after the painting operation; when the exit sensor detects that the reduction motor is approaching, the drying nozzle stops running, and the exit dustproof roller shutter is rolled up and opened, so that the detection motor after the painting operation can leave the core operation area and enter the next operation procedure.

[0127] The control system topology structure of the automated painting production line before the production line transformation is as follows: Figure 7 shown.

[0128] PLC is responsible for the control and coordination of the entire control system. In addition to being used for this control system, PLC is also used for other tasks, and its DI / DO interfaces are all occupied. Therefore, a distributed AI / DI module and a traditional distributed DO module are expanded through its built-in Profibus communication interface and Profibus communication bus to realize the indirect detection and indirect control of the sensors or controlled devices of this system by PLC. PLC, distributed AI / DI module and traditional distributed DO module are located in the control room at the far end of the automated painting operation industry. To ensure that the core operation area is clean and tidy, AI cable, DI cable 1, DI cable 2, DI cable 3, DI cable 4, DO cable 1, DO cable 2, DO cable 3, DO cable 4, DO cable 5 and DO cable 6 are pre-buried in the wire conduit. Figure 7 Above the rail.

[0129] Traditional distributed DO modules do not have any detection or diagnostic functions for DO cables (output cables) and terminal devices connected to DO cables. The circuit diagram is as follows: Figure 6 When working, the core processor communicates with the PLC through the Profibus interface circuit and the Profibus interface, receives control instructions from the PLC in real time, and then the core controller controls DO interface 1-DO interface 8 according to the instructions.

[0130] According to statistics, within one year after the automated painting production line was deployed and used, due to the combined effects of paint corrosion in the air of the core operating area and accelerated aging due to high temperature, there were 26 failures of cables or equipment such as DO cable 3, DO cable 4, DO cable 5, paint nozzles, drying nozzles and heaters. Since the core operating area is not suitable for maintenance personnel to perform maintenance work without shutting down the machine, and each time it takes a long time to find, troubleshoot and solve the fault, especially when troubleshooting the cables in the pre-buried wire conduit above the guide rail, the operation is difficult and the maintenance work is extremely time-consuming. The unplanned downtime caused by fault maintenance is as high as more than 700 hours.

[0131] like Fig. 9 As shown, the circuit principle block diagram of the distributed I / O module equipped with the present invention is shown. Compared with the traditional distributed DO module, only all the load switches are replaced by the disconnection resonance diagnosis device provided by the present invention.

[0132] like Fig.10 As shown, the system topology diagram after the control system of the automatic painting production line is transformed by using the distributed DO module equipped with the present invention. Compared with before the transformation, only the traditional distributed DO module is replaced with the distributed DO module equipped with the present invention.

[0133] According to statistics, within one year after the transformation and commissioning, the distributed DO module equipped with the present invention issued a total of 7 fault alarms, all of which were DO cable disconnection alarms, and accurately located the disconnection position during the 7 fault alarms. In addition, the distributed DO module equipped with the present invention also prompted 33 potential faults caused by aging of DO terminal equipment and aging of DO cables.

[0134] The unmanned assembly production line had 7 automation control system failures caused by DO cables (output cables) and terminal devices connected to the DO cables. The distributed I / O module of the present invention triggered alarms for the above 7 failures and accurately located the fault points. In addition, 11 potential failures caused by aging of DO terminal equipment were prompted. According to the previous maintenance and repair experience of the unmanned assembly production line, this measure shortened the unplanned downtime or production stoppage time by more than 550 hours, saving immeasurable economic losses.

[0135] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A disconnection resonance diagnostic device, characterized in that: include: Coprocessor, load switch, carrier generator, unidirectional coupler, DC detector, DC demodulator, resonant detector and high frequency demodulator; The coprocessor is connected to the load switch, the carrier generator, the DC detector and the resonance detector respectively, and is used to operate the load switch to output a load signal, and to operate the carrier generator to send a modulated carrier signal with adjustable frequency, and to diagnose the measurement signals of the DC detector and the resonance detector respectively to obtain diagnosis results, and to confirm the disconnection position based on the diagnosis results; The one-way coupler is connected to the load switch and the carrier generator respectively, and the one-way coupler is used to load the modulated carrier signal generated by the carrier generator into the output signal of the load switch to obtain a modulated load signal; The DC demodulator is connected to a DC detector, and is used to demodulate a DC signal from the modulated load signal and transmit the DC signal to the DC detector for detection by the DC detector; and The high frequency demodulator is connected to the resonance detector, and the high frequency demodulator is used to demodulate the modulated carrier from the modulated load signal and transmit it to the resonance detector for detection by the resonance detector; as well as The wire break position is determined based on the first change result of the real-time resonant voltage amplitude relative to the initial resonant voltage amplitude, the second change result of the initial disconnected DC component amplitude relative to the real-time disconnected DC component amplitude, and the third change result of the initial closed DC component amplitude relative to the real-time closed DC component amplitude.

2. The disconnection resonance diagnosis device according to claim 1, characterized in that: The broken line resonance diagnostic device comprises a first port and a second port; The first port is used to connect to an external host processor communication bus; and The second port is used to connect to an output cable.

3. The disconnection resonance diagnosis device according to claim 1, characterized in that: The frequency range of the modulated carrier wave emitted by the carrier wave generator is 1.50 MHz-60.00 MHz.

4. A method for diagnosing disconnection resonance, characterized in that: The method comprises using the disconnection resonance diagnosis device according to any one of claims 1 to 3 to perform diagnosis, and the method comprises: Get the real-time resonant voltage amplitude U relative to the initial resonant voltage amplitude U S The first change result; Get the initial disconnection DC component amplitude VO S A second change result relative to the real-time disconnection of the DC component amplitude VO; Get the initial closed DC component amplitude VC S a third change result relative to the real-time closed DC component amplitude VC; and The wire break position is determined based on the first change result of the real-time resonant voltage amplitude relative to the initial resonant voltage amplitude, the second change result of the initial disconnected DC component amplitude relative to the real-time disconnected DC component amplitude, and the third change result of the initial closed DC component amplitude relative to the real-time closed DC component amplitude.

5. The disconnection resonance diagnosis method according to claim 4, characterized in that: Get the real-time resonant voltage amplitude U relative to the initial resonant voltage amplitude U S The first changes result in: The highest frequency point of the resonant voltage amplitude of the modulated carrier signal emitted by the carrier generator when the load switch disconnection operation is performed for the first time is obtained, and the highest frequency point of the resonant voltage amplitude is used as the initial resonant frequency point f S ; Get the current resonant voltage amplitude as the initial resonant voltage amplitude U S ; Each time the load switch is disconnected thereafter, at the initial resonant frequency f S Transmitting a modulated carrier signal to an output cable and measuring a resonance voltage amplitude, and taking the resonance voltage amplitude as a real-time resonance voltage amplitude U; and Based on the real-time resonance voltage amplitude U relative to the initial resonance voltage amplitude U S The first change result is obtained by the change of 6. The disconnection resonance diagnosis method according to claim 4, characterized in that: Get the initial disconnection DC component amplitude VO S The second change result relative to the real-time disconnection of the DC component amplitude VO includes: Obtain the DC component in the output cable when the load switch disconnection operation is performed for the first time, and use the DC component as the initial disconnection DC component amplitude VO S ; Each time the load switch disconnection operation is performed thereafter, a DC component in the output cable is obtained as a real-time disconnection DC component amplitude VO; and Based on the initial disconnection DC component amplitude VO S The second change result is obtained relative to the change of the real-time disconnection DC component amplitude VO.

7. The disconnection resonance diagnosis method according to claim 4, characterized in that: Get the initial closed DC component amplitude VC S The third change result relative to the real-time closed DC component amplitude VC includes: Get the DC component in the output cable when the load switch is closed for the first time, and use it as the initial closed DC component amplitude VC S ; Each time the load switch closing operation is performed thereafter, the DC component in the output cable is measured as a real-time closing DC component amplitude VC; and Based on the initial closed DC component amplitude VC S The third change result is obtained relative to the change of the real-time closed DC component amplitude VC.

8. The disconnection resonance diagnosis method according to claim 4, characterized in that: Also includes: Get the minimum and maximum length of the output cable when transmitting a modulated carrier signal in the range of 0.30MHz-60.00MHz; An output cable capable of forming an antenna effect when transmitting a modulated carrier signal within a range of 0.30 MHz to 60.00 MHz is determined based on the minimum length and the maximum length of the output cable.

9. The disconnection resonance diagnosis method according to claim 4, characterized in that: When the disconnection position is the output cable, the disconnection resonance diagnosis device readjusts the resonance to obtain a new resonance frequency point as the real-time resonance frequency point when the disconnection position is the output cable; Obtaining the output lengths between all possible breakpoints of the output cable and the break resonance diagnostic device, recorded as a breakpoint distance set L; and The breakpoint position is determined based on the breakpoint distance set L.

10. The disconnection resonance diagnosis method according to claim 9, characterized in that: Determining the breakpoint position based on the breakpoint distance set L includes: determining the breakpoint position based on the following formula: <h2 style=";text-align:left;direction:ltr">L = {L1,L2,L3…L<h2 style=";text-align:left;direction:ltr"> n <h2 style=";text-align:left;direction:ltr">}(n=N<h2 style=";text-align:left;direction:ltr"> * <h2 style=";text-align:left;direction:ltr"> ) Wherein, L represents the breakpoint distance set, and f is the wavelength of the modulated carrier signal.

Images