A connection-type intermittent fault simulation system

Abstract

The present invention relates to a connection type intermittent fault simulation system, which includes a fault display unit, a signal transceiver, a power supply unit, a fault simulation board, a main controller, an operation display unit and a host computer; the signal transceiver transmits detection signals to the fault simulation board through at least one cable and receives feedback signals sent by the fault simulation board; the fault display unit is used to display the state of the feedback signals; the power supply unit provides corresponding power supplies to the fault simulation board and the main controller respectively, the main controller receives control commands sent by the host computer and transmits the control commands to the fault simulation board, the fault simulation board receives the control commands sent by the main controller, and converts the control commands into corresponding state signals by controlling the states of mechanical switches and / or electronic switches, and feeds back the state signals to the main controller; the operation display unit receives the state signals sent by the main controller and displays the state signals.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and particularly relates to a connection type intermittent fault simulation system. Background Art

[0002] When using a cable for signal transmission, due to factors such as vibration or a complex environment, intermittent faults such as momentary interruption and momentary short circuit may occur in the signal within the cable, affecting the normal transmission of the signal. When the intermittent fault lasts for a long time or occurs frequently, it may cause serious safety accidents. The intermittent faults in aviation cables are very difficult to diagnose and eliminate due to their accidental nature and short single duration. In the prior art, a cable fault location analyzer is generally used to detect the intermittent faults in the cable. However, before the cable fault location analyzer is put into use, its detection performance needs to be debugged and verified. Therefore, a device under test with connection type intermittent faults needs to be provided. However, it is very difficult to provide a real intermittent fault device, and the occurrence of intermittent faults cannot be preset. Therefore, it is very difficult to use a real intermittent fault device to verify the detection performance of the cable fault location analyzer. Summary of the Invention

[0003] The present invention aims at the existing technical problems and provides a connection type intermittent fault simulation system.

[0004] The technical solution for the present invention to solve the above technical problems is as follows: A connection type intermittent fault simulation system, characterized in that it includes a fault display unit, a signal transceiver device, a power supply unit, a fault simulation board, a main controller, an operation display unit, and a host computer; the signal transceiver device is electrically connected to the fault display unit and the fault simulation board respectively, the power supply unit is electrically connected to the fault simulation board and the main controller respectively, the main controller is electrically connected to the fault simulation board and the operation display unit respectively, and the host computer is electrically connected to the main controller; the signal transceiver device transmits a detection signal to the fault simulation board through at least one cable and receives a feedback signal sent by the fault simulation board; the fault display unit is used to display the state of the feedback signal received by the signal transceiver device; the power supply unit provides corresponding power to the fault simulation board and the main controller respectively, the main controller receives a control command sent by the host computer and transmits the control command to the fault simulation board, the fault simulation board receives the control command sent by the main controller, and converts the control command into a corresponding state signal by controlling the state of a mechanical switch and / or an electronic switch, and feeds back the state signal to the main controller, and the operation display unit receives the state signal sent by the main controller and displays the state signal through an indicator light and / or text.

[0005] On the basis of the above technical solution, in order to achieve convenient use and equipment stability, the present invention can further improve the above technical solution as follows:

[0006] Furthermore, the host computer sends control commands to the main controller according to a certain excitation period and excitation mode, and transmits them to the fault simulation board through the main controller, so as to generate corresponding signal states. An operation interface is provided on the host computer, which can control the states of the channels where each switch is located respectively. The default state and the state after reset are normal states; in all fault modes, within two seconds after the fault simulation is completed, it will automatically switch to the normal state.

[0007] Furthermore, the state signal is normal, short circuit or open circuit. When the state signal is "normal", the signal indicator light is green; when the state signal is "short circuit", the signal indicator light is yellow; when the state signal is "open circuit", the signal indicator light is red. At the same time, the state signal can also be represented by corresponding text.

[0008] Furthermore, the excitation mode is random excitation, single excitation or periodic excitation. The random excitation means that the occurrence of the fault is random and does not require specific conditions; the single excitation means that a fault can be generated once according to the set time; the periodic excitation means that periodic faults can be generated regularly according to the set period.

[0009] Furthermore, the excitation period includes the excitation time period, the number of excitations and the excitation moment. When the fault excitation mode is single excitation, the excitation moment and the fault duration of the single excitation can be set; when the fault excitation mode is random excitation, the number of random excitations and the fault duration can be set; when the fault excitation mode is periodic excitation, the time period of the periodic excitation, the fault duration and the number of excitations can be set.

[0010] Furthermore, the cable is a coaxial cable and / or a shielded cable, and the mechanical switch or electronic switch is individually controllable and corresponds to the number of cables. An electronic switch or a mechanical switch is added to the cable for transmitting the detection signal, and the switch is switched by controlling the signal, so as to realize the free conversion of the three state signals of "normal", "open circuit" and "short circuit".

[0011] Furthermore, the duration of the state signal generated by the mechanical switch is ≤50 ms, and the duration of the state signal generated by the electronic switch is ≤100 ns. The mechanical switch uses a relay, and the electronic switch uses a microwave switch.

[0012] The beneficial effects of the present invention are as follows: According to the pulse reflection principle, the signal transceiver device transmits detection signals through a cable. By installing a fault simulation board on the cable for transmitting detection signals and enabling mechanical or electronic switches on the fault simulation board to freely switch between normal, short - circuit, and open - circuit states through control signals, the feedback signal sent from the fault simulation board to the signal transceiver device exhibits corresponding signal states. Therefore, the fault states that may occur during the transmission of detection signals are simulated. By adjusting the triggering mode and excitation period of the control signal, intermittent faults during the transmission of detection signals are simulated, and the accuracy of the signal transceiver device in detecting intermittent faults is verified by comparing the display results of the fault display unit and the operation display unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic structural diagram of the simulation system of the present invention;

[0014] Figure 2 is a schematic diagram of a 4 - way mechanical switch;

[0015] Figure 3 is a schematic diagram of a 1 - way electronic switch;

[0016] Figure 4 is a working schematic diagram of a 1 - way electronic switch;

[0017] Figure 5 is a control logic table of the electronic switch. DETAILED DESCRIPTION OF THE INVENTION

[0018] The principles and features of the present invention will be described below in conjunction with the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0019] Such as Figure 1As shown in the figure, a connection type intermittent fault simulation system, characterized in that it includes a fault display unit 111, a signal transceiver 110, a power supply unit 120, a fault simulation board 130, a main controller 140, an operation display unit 150 and a host computer 160; the signal transceiver 110 is electrically connected to the fault display unit 111 and the fault simulation board 130 respectively, the power supply unit 120 is electrically connected to the fault simulation board 130 and the main controller 140 respectively, the main controller 140 is electrically connected to the fault simulation board 130 and the operation display unit 150 respectively, and the host computer 160 is electrically connected to the main controller 140; the signal transceiver 110 transmits detection signals to the fault simulation board 130 through at least one cable and receives the feedback signals sent by the fault simulation board 130; the handheld cable fault location analyzer includes the signal transceiver 110 and the fault display unit 111, and the signal transceiver 110 sends detection signals through a cable, and the detection signal is a pulse signal; the fault display unit 111 is used to display the state of the feedback signal received by the signal transceiver 110; when the state of the mechanical switch or electronic switch on the fault simulation board 130 is "normal", there is no reflected signal in the feedback signal displayed by the fault display unit 111; when the state of the mechanical switch or electronic switch on the fault simulation board 130 is "open circuit", there is a positive reflected signal in the feedback signal displayed by the fault display unit 111; when the state of the mechanical switch or electronic switch on the fault simulation board 130 is "short circuit", there is a negative reflected signal in the feedback signal displayed by the fault display unit 111; the cable is connected to the J30J-66 core connector on the fault simulation board 130 through a BNC connector or an aviation plug, the power supply unit 120 includes an AC-DC module and a DC-DC module to convert the voltage into the working voltages of the main controller 140 and the fault simulation board 130, the main controller 140 uses an AC7020 core board to receive the control commands sent by the host computer 160 and transmits the control commands to the fault simulation board 130 through the AXI bus, the fault simulation board 130 receives the control commands sent by the main controller 140, converts the control commands into corresponding state signals by controlling the state of the mechanical switch and / or electronic switch, and feeds back the state signals to the main controller 140, and the operation display unit 150 receives the state signals sent by the main controller 140, that is, the switch state of the mechanical switch or electronic switch on the fault simulation board 130, and displays the state signals through indicator lights and / or text.

[0020] Among them, the principle of the connection type intermittent fault simulation system is that the time domain reflectometry method, also known as the pulse reflection method, sends a voltage pulse to the communication cable, and determines the fault point by using the principle that the time difference between the transmitted pulse and the reflected pulse at the fault point is proportional to the distance of the fault point.

[0021] Let the incident wave voltage of the cable be U i, the wave impedance of the normal cable is Z1, the equivalent wave impedance of the fault is Z2, the traveling wave propagates from Z1 to Z2, and the reflected voltage wave is U f , voltage reflection coefficient:

[0022] When it is open circuit, Z2 is infinite, and when it is short circuit, Z2 is 0. Therefore, it is possible to determine whether there is a fault in the line by the presence or absence of the reflected signal, and the type of fault can be judged by the polarity of the reflected signal.

[0023] The host computer 160 sends control commands to the main controller 140 according to a certain excitation period and excitation mode, and transmits them to the fault simulation board 130 through the main controller 140, so as to generate corresponding signal states. An operation interface is provided on the host computer 160, and the states of the channels where each switch is located can be controlled respectively. The default state and the state after reset are normal states, and within two seconds after the fault simulation is completed, it will automatically switch to the normal state.

[0024] The state signal is normal, short circuit or open circuit. When the state signal is "normal", the indicator light is green; when the state signal is "short circuit", the indicator light is yellow; when the state signal is "open circuit", the indicator light is red. At the same time, the state signal can also be represented by the corresponding text.

[0025] The excitation mode is random excitation, single excitation or periodic excitation. The random excitation means that the occurrence of the fault is random and does not require specific conditions; the single excitation means that a fault can be generated once according to the set time; the periodic excitation means that periodic faults can be generated regularly according to the set period.

[0026] The excitation period includes the excitation time period, the number of excitations and the excitation moment. When the excitation mode of the fault is single excitation, the excitation moment of the single excitation can be set, and the excitation moment can be input as an integer second from 1s to 100s; when the excitation mode of the fault is random excitation, the number of random excitations can be set, and the number of random excitations can be input as an integer value from 1 to 100; when the excitation mode of the fault is periodic excitation, the number of excitations and the time period of the periodic excitation can be set, the number of excitations can be input as an integer value from 1 to 100, and the time period can be set to step 10s, with a range of 10s - 100s.

[0027] The cable is a coaxial cable and / or a shielded cable. The shielded cable is a twisted pair shielded cable or a single twisted shielded cable. The mechanical switch or the electronic switch is individually controllable and corresponds to the number of cables. An electronic switch or a mechanical switch is added to the cable, and through the control signal, the switch can be freely switched between the three states of "normal", "open circuit" and "short circuit". The mechanical switch or the electronic switch defaults to the normal working state when powered on for the first time.

[0028] The duration of the status signal generated by the mechanical switch is ≤ 50 ms, and the duration of the status signal generated by the electronic switch is ≤ 100 ns. The mechanical switch uses a relay, and the electronic switch uses a microwave switch. By using different forms of switches, intermittent faults of different frequencies are simulated.

[0029] As Figure 2 Shown in the schematic diagram of the mechanical switch, taking the M_CTRL1 channel, i.e., the first mechanical switch, as an example, three states of the first mechanical switch can be realized, and its control signals are M_CTRL1_A and M_CTRL1_B respectively. When the M_CTRL1_A control signal is set to high level, the K2 relay acts, and the first-path mechanical switch is in a short-circuit state, and the indicator light corresponding to the first channel shows yellow; when the M_CTRL1_A control signal is set to low level, the K2 relay is in the normally closed state, and when the M_CTRL1_B control signal is set to high level, the K1 relay acts, and the first-path mechanical switch is in an open-circuit state, and the indicator light corresponding to the first channel shows red; when both M_CTRL1_A and M_CTRL1_B are set to low level, both the K2 and K1 relays are in the normally closed state, and the first-path mechanical switch is in a normal state, and the indicator light corresponding to the first channel shows green. Among them, level conversion is performed through the optocoupler isolation chip VOMA617A-3X001T, and its action time is ≤ 10 us; the relay is driven by the ULN2803 Darlington tube, and its action time is ≤ 1 us; the G6S-2F-DC12 relay is used to simulate the mechanical switch, and its action time is ≤ 0.5 ms.

[0030] As Figures 3 to 5 Shown, taking the E_CTRL1 channel, i.e., the first electronic switch, as an example, three states of the first electronic switch can be realized. Its control signals are E_CTRL1_A1, E_CTRL1_B1, E_CTRL1_A2, and E_CTRL1_B2 respectively. Among them, the logic level states of E_CTRL1_A1, E_CTRL1_B1, E_CTRL1_A2, and E_CTRL1_B2 are as Figure 5 Shown. By adding an inverter, it is ensured that the levels of the E_CTRL1_A1 and E_CTRL1_B1 control signals cannot be both "1" or "0" at the same time, and the levels of the E_CTRL1_A2 and E_CTRL1_B2 control signals cannot be both "1" or "0" at the same time. The microwave switch of model HMC190BMS8 realizes the simulation of the electronic switch, and its action time is ≤ 10 ns, and the switch can control the maximum DC 3 GHz signal.

[0031] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A connection type intermittent fault simulation system, characterized in that, It includes a fault display unit, a signal transceiver, a power supply unit, a fault simulation board, a main controller, an operation display unit and a host computer. The handheld cable fault location analyzer includes the signal transceiver and the fault display unit; the signal transceiver is electrically connected to the fault display unit and the fault simulation board respectively, the power supply unit is electrically connected to the fault simulation board and the main controller respectively, the main controller is electrically connected to the fault simulation board and the operation display unit respectively, and the host computer is electrically connected to the main controller; The signal transceiver transmits the detection signal to the fault simulation board through at least one cable and receives the feedback signal sent by the fault simulation board. The detection signal is a pulse signal; The fault display unit is used to display the status of the feedback signal received by the signal transceiver; the power supply unit provides corresponding power to the fault simulation board and the main controller respectively. The main controller receives the control command sent by the host computer and transmits the control command to the fault simulation board. The fault simulation board receives the control command sent by the main controller and converts the control command into a corresponding status signal by controlling the status of the mechanical switch and / or the electronic switch, and feeds back the status signal to the main controller. The operation display unit receives the status signal sent by the main controller and displays the status signal through the indicator light and / or text. The status signal is normal, short circuit or open circuit. The duration of the status signal generated by the electronic switch is ≤ 100 ns; Determine whether there is a fault in the line by the presence or absence of the reflection signal, and judge the fault type by the polarity of the reflection signal: When the status of the mechanical switch or the electronic switch on the fault simulation board is "normal", there is no reflection signal in the feedback signal displayed in the fault display unit; When the status of the mechanical switch or the electronic switch on the fault simulation board is "open circuit", there is a positive reflection signal in the feedback signal displayed in the fault display unit; When the status of the mechanical switch or the electronic switch on the fault simulation board is "short circuit", there is a negative reflection signal in the feedback signal displayed in the fault display unit.

2. The connection type intermittent fault simulation system according to claim 1, wherein The host computer sends a control command to the main controller according to a certain excitation period and excitation mode, and transmits it to the fault simulation board through the main controller, so as to generate a corresponding signal status.

3. The connection type intermittent fault simulation system according to claim 2, wherein The excitation mode is random excitation, single excitation or periodic excitation.

4. The connection type intermittent fault simulation system according to claim 2, wherein, The excitation period includes the time period of excitation, the number of excitations and the moment of excitation.

5. The connection type intermittent fault simulation system according to claim 1, characterized in that The cable is a coaxial cable and / or a shielded cable. The mechanical switch or the electronic switch is individually controllable and corresponds to the number of cables.

6. The connection type intermittent fault simulation system according to claim 1, characterized in that, The duration of the status signal generated by the mechanical switch is ≤ 50 ms.

Images