Device state and experiment wiring intelligent detection device and method of electrician experiment table

Abstract

The invention provides a device state and experiment wiring intelligent detection device and method for an electrician experiment table, and the device comprises a microprocessor, an impedance measurement module and a plurality of groups of solid-state relay control modules, and each group of solid-state relay control module comprises two normally-open contact type solid-state relays. The input ends of the two solid-state relays are both connected with the microprocessor, each wiring terminal of the experiment table is connected with the input end and the output end of the impedance measurement module through normally open contacts of the two solid-state relays of the group of solid-state relay control modules, and the impedance measurement module is used for measuring the impedance value between the two wiring terminals. And the microprocessor compares the measured impedance value between the two wiring terminals with the normal impedance value of the device or the impedance value between the terminals when the wiring is correct, and judges whether the state of the device and the experimental wiring are wrong or not according to the comparison result. The device can be used for intelligent detection of device states and experiment wiring, the experiment efficiency is improved, and short-circuit accidents are prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical engineering experimental benches, and particularly to an intelligent detection device and method for the device state and experimental wiring of an electrical engineering experimental bench. Background Art

[0002] An electrical engineering experimental bench uses 220V / 380V as the experimental voltage and is an experimental device for carrying out experimental projects of electrical engineering courses. Electrical engineering experimental benches are widely used in various domestic institutions of higher learning. Due to the high working voltage and great experimental safety risks, special attention should be paid to preventing personal safety. In addition, once experimental personnel make mistakes in wiring, it is extremely easy to cause a short circuit, which is the main reason for shortening the service life of experimental equipment, damaging devices and causing safety hazards such as electric shock. It not only threatens personal safety, increases the expenditure on experimental materials and maintenance costs, but also affects the experimental progress, with low experimental efficiency and increased psychological burden on teachers and students. In traditional electrical engineering experiments, usually students are responsible for experimental wiring operations. After completing the wiring, the teacher checks and then powers on the experiment. If the power is turned on without inspection, a short circuit is very likely to occur. This method leads to a large labor intensity and low efficiency for teachers, and it is also difficult for teachers to be 100% correct in their inspections.

[0003] The patent with the patent number 202210617504.2 and the invention name of "An Electrical Engineering Experimental Device with Intelligent Detection of Experimental Circuits and Its Detection Method" proposes a new configuration of an electrical engineering experimental device with intelligent detection of experimental circuits and its detection method, which has certain innovation, but requires a complete update of experimental equipment, especially cannot be achieved by transformation on a traditional electrical engineering experimental bench, and cannot detect the device state of the experimental bench. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides an intelligent detection device and method for the device state and experimental wiring of an electrical engineering experimental bench, which can be transformed on the basis of a traditional electrical engineering experimental bench, so as to realize intelligent self-checking of the device state of the experimental bench and intelligent detection of experimental circuit wiring, greatly improve the experimental efficiency and safety, and at the same time, the transformation investment cost is low, the economic technology is more reasonable, and it is suitable for popularization and application in institutions of higher learning.

[0005] The technical solution of the present invention includes a microprocessor, an impedance measurement module, and multiple groups of solid-state relay control modules. Each group of the solid-state relay control modules includes two solid-state relays. The input ends of the two solid-state relays in the same group of the solid-state relay control modules are both connected to the microprocessor. Each wiring terminal of the test bench is connected to the input end and the output end of the impedance measurement module through the normally open contacts of the two solid-state relays of a group of solid-state relay control modules. The impedance measurement module is used to measure the impedance value between two wiring terminals. The microprocessor compares the measured impedance value between these two wiring terminals with the normal impedance value of the device or the impedance value between the terminals when the wiring is correct, and judges whether the device state and the experimental wiring are incorrect according to the comparison result.

[0006] Furthermore, it further includes a locking circuit module. The locking circuit module is connected to the microprocessor. The locking circuit module protects the circuit. The locking circuit module includes a locking relay, a transistor, a three-phase contactor, and a start button. The transistor is respectively connected to the microprocessor and the locking relay. The locking relay is connected to the three-phase contactor. The locking relay includes a relay coil and a power-on locking contact. The relay coil is connected to the transistor. The power-on locking contact is connected to the three-phase contactor. The power-on locking contact opens or closes according to whether there is current in the relay coil. The start button is connected to the three-phase contactor to control the opening or closing of the three-phase contactor. When the power-on control port of the microprocessor outputs a low level, the transistor is cut off, and there is no current in the locking relay coil, so that the power-on locking contact remains normally open, avoiding the start button from controlling the three-phase contactor to close. When the power-on control port of the microprocessor outputs a high level, the transistor is turned on, and there is current in the locking relay coil, so that the power-on locking contact remains closed, and the start button controls the three-phase contactor to close.

[0007] Furthermore, an emergency stop button is provided on the three-phase contactor, so that power can be quickly cut off in case of an accident.

[0008] Furthermore, it further includes control buttons and a liquid crystal display module. The control buttons and the liquid crystal display module are both connected to the microprocessor. The control buttons control the operation of the microprocessor. The liquid crystal display module is used to display the experimental item selection menu, the device state, and the information on whether the experimental wiring is correct.

[0009] The present invention also provides a method for detecting the device state and experimental wiring of an electrical engineering test bench, including the following steps: S100: The power-on control port of the microprocessor outputs a low level to control the power-on locking contact of the locking circuit module to be in a normally open state.

[0010] S200: Device status detection. The impedance measurement module measures the impedance values of several devices to be measured respectively, compares the measurement results with the normal impedance values of the corresponding devices, and determines whether the corresponding devices are normal according to the comparison results.

[0011] S300: Wiring detection for experimental items. After all the devices to be measured are detected as normal in step S200 and the wiring for the experimental items is completed, select the experimental item on the liquid crystal display module through the control button, compare the impedance values between each wiring terminal in the measured experimental item with the normal impedance values when the wiring is correct for the selected experimental item, and determine whether the experimental wiring is correct.

[0012] S400: After the device status and experimental wiring detections are all correct, the microprocessor outputs a high level at the power-on control port, controls the power-on latching contact of the latching circuit module to be in the closed state. At this time, press the start button, the main contacts of the three-phase contactor close, the experimental circuit is powered on, and the experiment starts.

[0013] Further, in step S100, the microprocessor outputs a low level at the power-on control port, the transistor of the latching circuit module is cut off, there is no current in the relay coil of the latching relay, the power-on latching contact is in the normally open state, the start button cannot control the three-phase contactor to close, the experimental circuit is in the open state, and the experiment cannot be carried out.

[0014] Further, in step S200, the microprocessor controls the normally open contacts of the solid-state relays corresponding to the two wiring terminals of the device to be measured to close through the I / O control port, so that the two wiring terminals of the device to be measured are respectively connected to the input end and the output end of the impedance measurement module, thereby measuring the impedance value of the device, comparing the measured impedance value of the device with the normal impedance value of the device, determining whether the corresponding device is normal or faulty according to the comparison results. If there is a fault, the information of the faulty device is displayed on the liquid crystal display module.

[0015] The technical solution provided by the embodiment of the present invention has the following advantages compared with the prior art: Each terminal of the device under test is connected to the input and output ends of the impedance measurement module respectively through the normally open contacts of two solid-state relays of a group of solid-state relay control modules. When detecting the device state, the microprocessor controls one solid-state relay of the solid-state relay control module of one terminal of the device to communicate with the input end of the impedance measurement module, and controls one solid-state relay of the solid-state relay control module of the other terminal of the device to communicate with the output end of the impedance measurement module. At this time, the impedance measurement module measures the impedance value between the two terminals of the device under test. The microprocessor compares the measurement result with the normal impedance value of the device, and judges whether the corresponding device is normal according to the comparison result. After the normal detection, then detect the impedance values between the respective terminals in the experimental items, compare the impedance values between the respective terminals in the measurement experimental items with the impedance values between the terminals when the selected experimental item is correctly wired, and judge whether the experimental wiring is correct according to the comparison result. Compared with the prior art, the present invention is applied to a traditional electrical engineering test bench, and before the experiment starts, it detects the states of each device and whether the connections between the devices are correct in advance, which can prevent in advance and avoid experimental accidents caused by device problems or wiring errors during the experiment, reduce the impact damage of short circuits on the devices and the power supply lines, extend the service life of the facilities, and reduce the consumption and maintenance costs of experimental equipment.

[0016] Other advantages, objectives and features of the present invention will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0018] Figure 1 Schematic diagram of the overall circuit layout of the detection device for one embodiment of the present invention; Figure 2 Schematic diagram of the overall circuit structure of the detection device for one embodiment of the present invention; Figure 3 Panel diagram of the control buttons and the liquid crystal display module for one embodiment of the present invention; Figure 4 Schematic diagram of the connection for detecting the wiring of the experimental items for one embodiment of the present invention.

[0019] Reference numerals: 1. First terminal; 2. Second terminal; 3. Third terminal; 4. Fourth terminal; 5. Fifth terminal; 6. Sixth terminal; 7. Seventh terminal; 8. Eighth terminal. Detailed implementation mode

[0020] The following combines with the attached drawings to describe in detail a specific implementation mode of the present invention. However, it should be understood that the protection scope of the present invention is not limited by the specific implementation mode.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the attached drawings. It is only for the convenience of describing the technical solution of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present invention.

[0022] In the description of the embodiments of the present invention, unless otherwise specified, the meaning of "a plurality" refers to two or more.

[0023] In the description of the embodiments of the present invention, the device under test all has two terminals.

[0024] As Figure 1 and Figure 2 shown, Figure 2 In the figure, K represents a solid-state relay, A represents the input end of the solid-state relay, B and C represent both ends of the normally open contact of the solid-state relay. The present invention provides an intelligent detection device for the state of electrical experimental bench devices and experimental wiring, including a microprocessor, an impedance measurement module, and multiple groups of solid-state relay control modules. Each group of solid-state relay control modules includes two solid-state relays. The input ends of the two solid-state relays in the same group of solid-state relay control modules are all connected to the microprocessor. Each terminal of the experimental bench is connected to the input end and output end of the impedance measurement module through the normally open contacts of the two solid-state relays in a group of solid-state relay control modules. The impedance measurement module is used to measure the impedance value between two terminals. The microprocessor compares the measured impedance value between these two terminals with the normal impedance value of the device or the impedance value between the terminals when the wiring is correct, and judges whether the state of the device and the experimental wiring are incorrect according to the comparison result.

[0025] Each terminal of the device under test is connected to the input and output terminals of the impedance measurement module through the normally open contacts of two solid-state relays in a group of solid-state relay control modules. When detecting the device state, the microprocessor controls one solid-state relay in the solid-state relay control module of one terminal of the device to be connected to the input terminal of the impedance measurement module, and controls one solid-state relay in the solid-state relay control module of the other terminal of the device to be connected to the output terminal of the impedance measurement module. At this time, the impedance measurement module measures the impedance value between the two terminals of the device under test. The microprocessor compares the measurement result with the normal impedance value of the device, and judges whether the corresponding device is normal according to the comparison result. After the normal detection, the impedance values between each terminal in the experimental project are detected, and the impedance values between each terminal in the measurement experimental project are compared with the impedance values between the terminals when the selected experimental project is correctly wired. According to the comparison result, it is judged whether the experimental wiring is correct. Compared with the prior art, the present invention is applied to a traditional electrical engineering test bench, and before the experiment starts, the states of each device and whether the connections between each device are correct are detected in advance, which can prevent in advance and avoid experimental accidents caused by device problems or wiring errors during the experiment, reduce the impact damage of short circuits on devices and power supply lines, extend the service life of facilities, and reduce the consumption and maintenance costs of experimental equipment.

[0026] Further, in the same group of solid-state relay control modules, the C end of the normally open contact of one solid-state relay is connected to the input terminal of the impedance measurement module through impedance measurement line 1, and the C end of the normally open contact of the other solid-state relay is connected to the output terminal of the impedance measurement module through impedance measurement line 2.

[0027] Further, in the same group of solid-state relay control modules, the B ends of the normally open contacts of the two solid-state relays are both connected to the terminal, and the terminal is connected to the device under test.

[0028] When measuring the impedance value, each device can be equivalent to an impedance element. Under normal circumstances, the equivalent impedance value of a certain device is relatively stable, such as the internal impedance of a voltmeter, the internal impedance of an ammeter, the impedance of a motor winding, the impedance of a fluorescent lamp filament, the impedance of a contactor coil, etc. There are also some devices that are themselves resistors, inductors, and capacitor elements with definite parameters. Therefore, by actually measuring the impedance between the terminals of each device on this batch of test benches in a good state of the electrical engineering test bench, the arithmetic average value of the impedance of each device is obtained as the standard impedance of the device, and the maximum error of the measured results of the impedance values of each terminal is used as the allowable deviation threshold. The normal impedance values and the allowable deviation threshold between the terminals of each device on the test bench are stored in the memory unit of the microprocessor for subsequent comparison after detecting the impedance value of the device to judge whether it is normal.

[0029] In the embodiment provided by the present invention, a latching circuit module is further included. The latching circuit module is connected to the microprocessor and is used to protect the circuit. The latching circuit module includes a latching relay, a transistor, a three-phase contactor, and a start button. The transistor is respectively connected to the microprocessor and the latching relay. The latching relay is connected to the three-phase contactor. The latching relay includes a relay coil and a power-on latching contact. The relay coil is connected to the transistor, and the power-on latching contact is connected to the three-phase contactor. The power-on latching contact is opened or closed according to whether there is current in the relay coil. The start button is connected to the three-phase contactor to control the opening or closing of the three-phase contactor. When the power-on control port of the microprocessor outputs a low level, the transistor is cut off, there is no current in the latching relay coil, and the power-on latching contact is in the normally open state. At this time, even if the start button is pressed, the three-phase contactor cannot be controlled to close. When the power-on control port of the microprocessor outputs a high level, the transistor conducts, there is current in the latching relay coil, and the power-on latching contact is kept closed. At this time, pressing the start button can control the three-phase contactor to close.

[0030] In the embodiment provided by the present invention, an emergency stop button is provided on the three-phase contactor so that the power can be quickly cut off in case of an accident.

[0031] In the embodiment provided by the present invention, as Figure 3 shown, a control button and a liquid crystal display module are further included. The control button is connected to the liquid crystal display module and the microprocessor. The control button is used to control the operation of the microprocessor. The liquid crystal display module is used to display the experimental item selection menu, the device status, and the information on whether the experimental wiring is correct.

[0032] The present invention also provides a method for detecting the device status and experimental wiring of an electrical engineering experiment bench, including the following steps: S100: The power-on control port of the microprocessor outputs a low level to control the power-on latching contact of the latching circuit module to be in the normally open state.

[0033] S200: Device status detection. Measure the impedance values of several devices to be measured, compare the measurement results with the normal impedance values of the devices, and judge whether the corresponding devices are normal.

[0034] S300: Experimental item wiring detection. After all the devices to be measured are detected to be normal in step S200 and the experimental item wiring is completed, select the experimental item on the control button and the liquid crystal display module, compare the impedance values between each wiring terminal in the measured experimental item with the impedance values between the terminals when the selected experimental item is correctly wired, and judge whether the experimental wiring is correct.

[0035] S400: After the device status and experimental wiring are all checked correctly, the microprocessor power-on control port outputs a high level, and the power-on lock contact of the control lock circuit module is in a closed state. At this time, press the start button, the main contacts of the three-phase contactor are closed, and the experimental circuit is powered on, and the experiment can begin.

[0036] In the embodiment provided by the present invention, in step S100, the microprocessor power-on control port outputs a low level, the transistor of the locking circuit module is cut off, the relay coil of the locking relay has no current, and the power-on locking contact is in a normally open state. At this time, even if the start button is pressed, the three-phase contactor cannot be controlled to close, causing the experimental circuit to be in an open state and the experiment cannot be carried out.

[0037] In the embodiment provided by the present invention, in step S200, the impedance value between the two terminals of the device in a normal state is basically stable, and the microprocessor controls the normally open contacts of the solid-state relay corresponding to the two terminals of the device under test to close through the I / O control port, so that the two terminals of the device under test are connected to the impedance measurement line 1 and the impedance measurement line 2 respectively, thereby measuring the impedance value of the corresponding device, comparing the measured impedance value of the device with the normal impedance value of the device, and determining whether the corresponding device is normal or faulty. If a fault exists, the faulty device information is displayed on the liquid crystal display module.

[0038] Specifically, when the impedance of a device needs to be measured, the two terminals of the device are numbered i and j. The microprocessor sends a control level through the I / O control port to make the solid-state relay A 2i-1 If the port is high, the solid-state relay K 2i-1 The normally open contact of the solid-state relay A is closed, and the terminal i is connected to the impedance measurement line 1; the microprocessor continues to send control levels through the I / O control port to make the solid-state relay A 2j If the port is high, the solid-state relay K 2j The normally open contact of is closed, terminal j is connected to impedance measurement line 2, and terminals i and j of the test bench are connected to two impedance measurement lines respectively. The impedance measurement chip automatically completes the impedance measurement between terminals ij. The microprocessor reads the measured impedance value between the two terminals and compares it with the normal impedance value of the device. If the deviation is within the set allowable deviation threshold, the device is "intact"; if it exceeds the threshold, it is marked as "faulty"; the impedance measurement and judgment methods between the terminals of other devices are similar.

[0039] In the embodiment provided by the present invention, in step S300, the impedance value between any two wiring terminals in the experimental project is measured, and the measurement result is compared with the impedance value between the two wiring terminals when the selected experimental project is correctly wired, so as to determine whether the wiring between several devices is correct or incorrect. If there is an error, the error device information is displayed on the liquid crystal display module.

[0040] Specifically, each experimental item has a definite experimental wiring. When the wiring is correct, for several connection terminals connected by wires between experimental devices, since they are short-circuited by the wires, the impedance measured between these terminals is approximately zero. For terminals without wire connections between devices, since they are open circuits, the impedance measured between these terminals is approximately infinite. The impedance between the terminals of the experimental device itself will also change due to the line connection impedance.

[0041] As Figure 1 、 Figure 2 and Figure 4 shown, Figure 4 In the figure, the numbers are the connection terminal numbers. During detection, the microprocessor sends a control level through the I / O control port to sequentially control the normally open contacts of the solid-state relays of each experimental terminal to close. First, measure the impedance between the first connection terminal 1 and the second connection terminal 2. The microprocessor sends a control level through the I / O control port to make the A1 port at a high level, then the normally open contact of the solid-state relay K1 closes, and the first connection terminal 1 is connected to the first impedance measurement line; the microprocessor continues to send a control level through the I / O control port to make the A4 port at a high level, then the normally open contact of the solid-state relay K4 closes, and the second connection terminal 2 is connected to the second impedance measurement line, so that the first connection terminal 1 and the second connection terminal 2 of the device are respectively connected to the two impedance measurement lines. The impedance measurement module automatically completes the impedance measurement between the first connection terminal 1 and the second connection terminal 2. The microprocessor reads the impedance value between the first connection terminal 1 and the second connection terminal 2, compares it with the normal impedance value between the first connection terminal 1 and the second connection terminal 2 when the wiring is correct. If the deviation is within the set threshold, the wiring is "correct"; if it exceeds the threshold, it is marked as "wrong".

[0042] For example: The device between the second connection terminal 2 and the third connection terminal 3 is an incandescent lamp, the device between the fourth connection terminal 4 and the fifth connection terminal 5 is a voltmeter, and the device between the sixth connection terminal 6 and the seventh connection terminal 7 is an ammeter. Among them, the wiring between the first connection terminal 1 and the second connection terminal 2, the second connection terminal 2 and the fourth connection terminal 4, the third connection terminal 3 and the fifth connection terminal 5, the third connection terminal 3 and the sixth connection terminal 6, and the seventh connection terminal 7 and the eighth connection terminal 8 are the wirings for correct experiments.

[0043] By controlling the conduction of the relay, the impedance between the first terminal 1 and the second terminal 2, the first terminal 1 and the third terminal 3, the first terminal 1 and the fourth terminal 4, the first terminal 1 and the fifth terminal 5, the first terminal 1 and the sixth terminal 6, the first terminal 1 and the seventh terminal 7, the first terminal 1 and the eighth terminal 8, the second terminal 2 and the third terminal 3, the second terminal 2 and the fourth terminal 4, the second terminal 2 and the fifth terminal 5, the second terminal 2 and the sixth terminal 6, the second terminal 2 and the seventh terminal 7, the second terminal 2 and the eighth terminal 8, the third terminal 3 and the fourth terminal 4, the third terminal 3 and the fifth terminal 5, the third terminal 3 and the sixth terminal 6, the third terminal 3 and the seventh terminal 7, the third terminal 3 and the eighth terminal 8, the fourth terminal 4 and the fifth terminal 5, the fourth terminal 4 and the sixth terminal 6, the fourth terminal 4 and the seventh terminal 7, the fourth terminal 4 and the eighth terminal 8, the fifth terminal 5 and the sixth terminal 6, the fifth terminal 5 and the seventh terminal 7, the fifth terminal 5 and the eighth terminal 8, the sixth terminal 6 and the seventh terminal 7, the sixth terminal 6 and the eighth terminal 8, the seventh terminal 7 and the eighth terminal 8 is measured to obtain the impedance value.

[0044] Obviously, when the connection is correct, the impedance between the first terminal 1 and the second terminal 2, the first terminal 1 and the fourth terminal 4, the second terminal 2 and the fourth terminal 4, the third terminal 3 and the fifth terminal 5, the third terminal 3 and the sixth terminal 6, the fifth terminal 5 and the sixth terminal 6, the seventh terminal 7 and the eighth terminal 8 is only the impedance of the experimental wire. The normal impedance value is between 0.1 ohm and 1 ohm. When the measured impedance between these terminals exceeds 2 ohms, it is determined that there is a problem of unconnected wire, broken wire or poor contact in the wiring.

[0045] Among them, the impedance between the first terminal 1 and the third terminal 3, the first terminal 1 and the fifth terminal 5, the first terminal 1 and the sixth terminal 6, the first terminal 1 and the seventh terminal 7, the first terminal 1 and the eighth terminal 8, the second terminal 2 and the third terminal 3, the second terminal 2 and the fifth terminal 5, the second terminal 2 and the sixth terminal 6, the second terminal 2 and the seventh terminal 7, the second terminal 2 and the eighth terminal 8, the third terminal 3 and the fourth terminal 4, the fourth terminal 4 and the sixth terminal 6, the fourth terminal 4 and the seventh terminal 7, and the fourth terminal 4 and the eighth terminal 8 is mainly the impedance of the incandescent lamp. Assuming that the normal internal resistance of the incandescent lamp is 10 ohms, when the measured impedance between these terminals exceeds 12 ohms, it is judged that there is a problem of unconnected wire, broken wire or poor contact. When the measured impedance between these terminals is less than 9 ohms, it is judged that there is a wiring error.

[0046] Among them, the impedance between the sixth terminal 6 and the seventh terminal 7, and the sixth terminal 6 and the eighth terminal 8 is mainly the impedance of the ammeter. Assuming that the normal internal resistance of the ammeter is 0.5 ohms, when the measured impedance between these terminals exceeds 2 ohms, it is judged that there is a problem of unconnected wire, broken wire or poor contact. When the measured impedance between these terminals is less than 0.4 ohms, it is judged that there is a wiring error. The main problem of wiring error is incorrect short circuit. When there is an unconnected wire or broken wire, the impedance generally exceeds 50,000 ohms, and when there is poor contact, it generally exceeds the normal value by several ohms to several thousand ohms.

[0047] That is, during detection, the microprocessor sends a control level through the I / O control port to sequentially control the normally open contacts of the solid-state relays of each experimental terminal to close. First, measure the impedance between the first terminal 1 and the second terminal 2. The microprocessor sends a control level through the I / O control port to make the A1 port at a high level, then the normally open contact of the solid-state relay K1 closes, and the first terminal 1 is connected to the first impedance measurement line; the microprocessor continues to send a control level through the I / O control port to make the A4 port at a high level, then the normally open contact of the solid-state relay K4 closes, and the second terminal 2 is connected to the second impedance measurement line, so that the first terminal 1 and the second terminal 2 of the device are respectively connected to the two impedance measurement lines. The impedance measurement module automatically completes the impedance measurement between the first terminal 1 and the second terminal 2. The microprocessor reads the impedance value between the first terminal 1 and the second terminal 2, compares it with the normal impedance value between the first terminal 1 and the second terminal 2 during correct wiring. If the deviation is within the set threshold, the wiring is "correct", and if it exceeds the threshold, it is marked as "error".

[0048] According to the method of the previous step, continue to complete the impedance measurement and judgment between all combinations of the first terminal 1 and the third terminal 3, the first terminal 1 and the fourth terminal 4... the first terminal 1 and the terminal, the second terminal 2 and the third terminal 3, the second terminal 2 and the fourth terminal 4... the second terminal 2 and the terminal n, etc.

[0049] In the embodiment provided by the present invention, in step S400, the power-on control port of the microprocessor outputs a high level, the transistor of the locking circuit module conducts, there is current in the relay coil of the locking relay, so that the power-on locking contact closes, and the start button is pressed, so as to control the main contacts of the three-phase contactor to close, the experimental circuit is powered on, and the experiment can start. At the same time, the self-holding contact of the three-phase contactor closes, making the locking circuit module in a conducting state.

[0050] Specifically, complete the impedance measurement and judgment between all terminals. If the wiring judgment of all terminals is "correct", the liquid crystal display shows "The wiring is correct and the experiment can be carried out". The power-on control port of the microprocessor P1.2 outputs a high level to control the locking relay to conduct, so that the "power-on locking contact" closes, releasing the power-on lock. The experimenter can press the "start button" of the locking circuit, the three-phase contactor closes, the experimental circuit is powered on, and the experimental project can be carried out. When the experimental circuit is powered on, the intelligent detection program is prohibited from running; if there is an "error" in the experimental wiring judgment, the information of the terminal with the "error" is displayed on the liquid crystal display module, and the power-on locking loop is maintained. Pressing the "start button" of the experimental device by the experimenter is invalid and the power-on experiment cannot be started; according to the error diagnosis information prompted by the liquid crystal display, after the experimenter corrects the wrong experimental wiring, the "confirm" key can be pressed to run the intelligent wiring detection again until the detection passes.

[0051] Press the "reset" key at any time, and the intelligent detection device resets and restarts. At this time, the experimental circuit is automatically powered off and the detection starts again.

[0052] It should be noted that in this article, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article or device including that element.

[0053] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those skilled in the art, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and the examples shown and described herein.

Claims

1. Intelligent detection device for the device state and experimental wiring of an electrical engineering experimental bench, characterized in that, It includes a microprocessor, an impedance measurement module, and multiple groups of solid-state relay control modules; Each group of the solid-state relay control modules includes two solid-state relays. The input ends of the two solid-state relays in the same group of the solid-state relay control modules are all connected to the microprocessor. Each wiring terminal of the test bench is connected to the input end and the output end of the impedance measurement module through the normally open contacts of the two solid-state relays of a group of solid-state relay control modules; The impedance measurement module is used to measure the impedance value between two wiring terminals. The microprocessor compares the measured impedance value between the two wiring terminals with the normal impedance value of the device or the impedance value between the terminals when the wiring is correct, and judges whether the device state and the experimental wiring are incorrect according to the comparison result.

2. The intelligent detection device for the device state and experimental wiring of the electrical engineering experimental bench according to claim 1, characterized in that, It also includes a locking circuit module. The locking circuit module is connected to the microprocessor, and the locking circuit module protects the circuit; The locking circuit module includes a locking relay, a transistor, a three-phase contactor, and a start button. The transistor is respectively connected to the microprocessor and the locking relay. The locking relay is connected to the three-phase contactor. The locking relay includes a relay coil and a power-on locking contact. The relay coil is connected to the transistor, and the power-on locking contact is connected to the three-phase contactor. The power-on locking contact is opened or closed according to whether there is current in the relay coil. The start button is connected to the three-phase contactor to control the opening or closing of the three-phase contactor; When the power-on control port of the microprocessor outputs a low level, the transistor is cut off, and there is no current in the locking relay coil, so that the power-on locking contact remains normally open, avoiding the start button from controlling the three-phase contactor to close. When the power-on control port of the microprocessor outputs a high level, the transistor conducts, and there is current in the locking relay coil, so that the power-on locking contact remains closed, and the start button controls the three-phase contactor to close.

3. The intelligent detection device for the device state and experimental wiring of the electrical engineering experimental bench according to claim 2, characterized in that, An emergency stop button is provided on the three-phase contactor, so that the power can be cut off quickly in case of an accident.

4. The intelligent detection device for the device state and experimental wiring of the electrical engineering experimental bench according to claim 2, characterized in that, It also includes control buttons and a liquid crystal display module. The control buttons and the liquid crystal display module are both connected to the microprocessor. The control buttons control the operation of the microprocessor, and the liquid crystal display module is used to display the experimental project selection menu, the device state, and the information on whether the experimental wiring is correct.

5. Method for detecting the state of electrical engineering experiment bench devices and experimental wiring, using the intelligent detection device for the state of electrical engineering experiment bench devices and experimental wiring as described in claim 4, characterized in that, It includes the following steps: S100: The power-on control port of the microprocessor outputs a low level to control the power-on locking contact of the locking circuit module to be in a normally open state; S200: Device state detection. The impedance measurement module measures the impedance values of several devices to be tested respectively, compares the measurement results with the normal impedance values of the corresponding devices, and judges whether the corresponding devices are normal according to the comparison results; S300: Experimental project wiring detection. After all the devices to be tested are detected to be normal in step S200 and the experimental project wiring is completed, select the experimental project on the liquid crystal display module through the control buttons, compare the impedance values between the wiring terminals in the measured experimental project with the normal impedance values when the wiring of the selected experimental project is correct, and judge whether the experimental wiring is correct; S400: After all the device status and experimental wiring detections are correct, the microprocessor power-on control port outputs a high level to control the power-on latching contact of the latching circuit module to be in a closed state. At this time, when the start button is pressed, the main contacts of the three-phase contactor close, the experimental circuit is powered on, and the experiment starts.

6. The method for detecting the device state and experimental wiring of an electrical engineering test bench according to claim 5, wherein, In step S100, the microprocessor power-on control port outputs a low level, the transistor of the latching circuit module is cut off, there is no current in the relay coil of the latching relay, the power-on latching contact is in a normally open state, the start button cannot control the three-phase contactor to close, the experimental circuit is in an open circuit state, and the experiment cannot be carried out.

7. The method for detecting the device state and experimental wiring of the electrical engineering experimental bench according to claim 5, wherein In step S200, the microprocessor controls the normally open contacts of the solid-state relays corresponding to the two wiring terminals of the device under test to close through the I / O control port, so that the two wiring terminals of the device under test are respectively connected to the input end and the output end of the impedance measurement module, thereby measuring the impedance value of the device. Compare the measured impedance value of the device with the normal impedance value of the device, and judge whether the corresponding device is normal or faulty according to the comparison result. If there is a fault, display the faulty device information on the liquid crystal display module.

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