Ground wire detection device and ground wire detection method

Abstract

The invention provides a ground wire detection device and a ground wire detection method. The ground wire detection device comprises a power supply module, a measuring resistor, a regression wire and a control module, the positive electrode of the power module is electrically connected with the first end of the grounding wire and a first grounding system through the measuring resistor, the negative electrode of the power module is electrically connected with the first end of the return wire, and the second end of the return wire is electrically connected with the second end of the grounding wire and a second grounding system. The control module is used for detecting the line voltage between the first end of the grounding line and the first end of the regression line, and according to the line voltage, the power supply voltage between the positive electrode and the negative electrode of the power supply module, the measurement resistance value of the measurement resistor, the regression line resistance value of the regression line and the equivalent resistance value range between the first grounding system and the second grounding system. And obtaining the grounding wire resistance value range of the grounding wire. Current detection does not need to be carried out on the ground wire, and the reliability of the whole impedance detection is improved.

Description

Technical Field

[0001] This invention relates to the field of electrical protection technology, specifically to a grounding wire detection device and a grounding wire detection method. Background Technology

[0002] A grounding wire, also known as a protective earthing wire, is used to electrically connect the casing or metal parts of electrical equipment to the grounding system, thereby ensuring electrical safety. When there is only one electrical device, there is also only one grounding wire, which connects the device to the corresponding grounding system. When there are multiple electrical devices, there are also multiple grounding wires. These wires can be divided into two parts: one part connects each device to its corresponding grounding system, and the other part connects each device to other electrical equipment.

[0003] Whether in a single power device scenario or a multi-power device scenario, the grounding wire provides a discharge path after a fault through a low impedance method, thereby achieving electrical protection. Therefore, the impedance of the grounding wire can measure its performance, and the performance characterizes the grounding wire's own state as well as the connection state between the grounding wire and the power device and / or the grounding system.

[0004] Existing technologies typically provide voltage to the grounding wire and detect the corresponding current using a current transformer to obtain the impedance of the grounding wire. However, this method has limitations in practical applications. When the current is too low, interference from the induced current in the circuit and the accuracy issues of the current transformer can prevent the acquisition of a stable and accurate current, ultimately affecting the reliability of the entire impedance detection. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a grounding wire detection device and a grounding wire detection method.

[0006] In one embodiment, the present invention provides a grounding wire detection device, which includes a power module, a measuring resistor, a return line, and a control module. The positive terminal of the power module is used to be electrically connected to the first end of the grounding wire and the first grounding system through the measuring resistor, the negative terminal of the power module is electrically connected to the first end of the return line, and the second end of the return line is used to be electrically connected to the second end of the grounding wire and the second grounding system. The control module is used to detect the line voltage between the first end of the grounding wire and the first end of the return wire. Based on the line voltage, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return wire resistance value of the return wire, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range is obtained.

[0007] In one embodiment, the control module is also electrically connected to the power supply module; The control module is used to control the power module to output different power supply voltages, thereby obtaining the grounding wire resistance range corresponding to each power supply voltage.

[0008] In one embodiment, the measuring resistor is an adjustable resistor and is electrically connected to the control module; The control module is used to control the measuring resistor to provide different measured resistance values, thereby obtaining the grounding wire resistance range corresponding to each measured resistance value.

[0009] Secondly, the present invention provides a method for detecting a grounding wire, which is applied to the grounding wire detection device in any of the above embodiments. The grounding wire detection method includes the following steps executed by a control module: The line voltage between the first end of the grounding wire and the first end of the return wire is detected. Based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return wire resistance value of the return wire, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range is obtained.

[0010] In one embodiment, the control module is also electrically connected to the power supply module; it detects the line voltage between the first end of the grounding wire and the first end of the return wire, and obtains the grounding wire resistance range based on the line voltage, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return wire resistance value of the return wire, and the equivalent resistance range between the first grounding system and the second grounding system, including: The control power module outputs different power voltages and detects the line voltage corresponding to each power voltage. For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the corresponding power supply voltage, the measured resistance, the regression line resistance, and the equivalent resistance range.

[0011] In one embodiment, the measuring resistor is an adjustable resistor and electrically connected to the control module; the line voltage between the first end of the grounding wire and the first end of the return line is detected; based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range is obtained, including: The control resistors are provided with different measured resistance values, and the line voltage corresponding to each measured resistance value is detected respectively; For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the power supply voltage, the measured resistance value corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

[0012] In one embodiment, the control module is also electrically connected to the power module, and the measuring resistor is an adjustable resistor and electrically connected to the control module; the line voltage between the first end of the grounding wire and the first end of the return line is detected, and the grounding wire resistance range is obtained based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, including: The control power module outputs different power voltages and the control measuring resistor provides different measuring resistance values. A power voltage and a measuring resistance value constitute a parameter group. Detect the line voltage corresponding to each parameter group separately; For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the parameter set corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

[0013] In one embodiment, after the step of obtaining the grounding wire resistance range corresponding to each line voltage based on the line voltage, the parameter set corresponding to the line voltage, the regression line resistance value, and the equivalent resistance range, the grounding wire detection method further includes the following steps performed by the control module: Determine the average resistance range among multiple grounding wire resistance ranges; The performance test results of the grounding wire are obtained based on the average resistance range and the preset standard grounding wire resistance.

[0014] In one embodiment, the performance test results of the grounding wire are obtained based on the average resistance range and a preset standard grounding wire resistance value, including: The preset standard grounding wire resistance value is matched within the average resistance range to obtain the matching result; If the matching result indicates that the preset standard grounding wire resistance value is within the average resistance range, then the first performance test result of the grounding wire is obtained. If the matching result indicates that the preset standard grounding wire resistance value is outside the average resistance range, then the second performance test result of the grounding wire is obtained.

[0015] In one embodiment, the average resistance range is divided into multiple candidate intervals distributed sequentially; if the matching result indicates that the preset standard grounding wire resistance is within the average resistance range, then the first performance test result of the grounding wire is obtained, including: If the matching result indicates that the preset standard grounding wire resistance value is within the average resistance value range, then the target candidate interval corresponding to the preset standard grounding wire resistance value in the average resistance value range is determined. Based on the distribution of the target candidate interval within the average resistance range, the first performance test result corresponding to the target candidate interval is obtained.

[0016] The above-described grounding wire detection device and method configure a power supply module, a measuring resistor, a return line, and a control module for grounding wires used to electrically connect multiple electrical devices. The control module can obtain the grounding wire resistance range based on the line voltage between the first end of the grounding wire and the first end of the return line, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first and second grounding systems. Since the equivalent resistance between the first and second grounding systems varies depending on the actual situation, the equivalent resistance range is used to consider its possible values, and a corresponding grounding wire resistance range is determined for each grounding wire. Although the final detected impedance of the grounding wire is expressed as a grounding wire resistance range, the grounding wire resistance range exhibited under different performance states is also different. Therefore, performance testing can be achieved based on the grounding wire resistance range. This application eliminates the need for current detection of the grounding wire, effectively avoiding the inability to obtain a stable and accurate current due to interference from induced current in the circuit and the accuracy problems of the current transformer, ultimately improving the reliability of the entire impedance detection. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram illustrating the connection relationship between the regression line, the measuring resistor, and the grounding wire in one embodiment of the present invention; Figure 2 This is a schematic diagram of the output potential and detection potential of the power module and the control module in one embodiment of the present invention; Figure 3 This is a schematic diagram of the equivalent circuit of the regression line, measuring resistance, and grounding wire in one embodiment of the present invention; Figure 4 This is a schematic diagram showing the connection between the measuring resistor and the control module in one embodiment of the present invention when the measuring resistor is an adjustable resistor; Figure 5 This is a schematic diagram showing the positional relationship between the preset standard grounding wire resistance value and the grounding wire resistance value range in one embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified. In this application, the term "exemplary" is used to mean "used as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to implement and use the invention. In the following description, details are set forth for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed herein.

[0021] Firstly, such as Figure 1 and Figure 2 As shown, in one embodiment, the present invention provides a grounding wire detection device, which includes a power supply module, a measuring resistor R1, a return line, and a control module.

[0022] The positive terminal of the power module is used to connect to the first end of the grounding wire and the first grounding system through the measuring resistor R1, respectively. The negative terminal of the power module is connected to the first end of the return line, and the second end of the return line is used to connect to the second end of the grounding wire and the second grounding system, respectively.

[0023] The power module is used to output power voltage through its positive and negative terminals, that is, the voltage difference between the potential Vc+ of the positive terminal of the power module and the potential Vc- of the negative terminal of the power module, which can be denoted as Vc.

[0024] Since the positive terminal of the power module, the measuring resistor R1, the grounding wire, the return line and the negative terminal of the power module are connected in series, when the power module outputs power voltage through its positive and negative terminals, a corresponding line voltage will be generated between the first end of the grounding wire and the first end of the return line. That is, the voltage difference between the potential V1+ at the first end of the grounding wire and the potential V1- at the first end of the return line can be denoted as V1.

[0025] The control module is used to detect the line voltage V1 between the first end of the grounding wire and the first end of the return wire. Based on the line voltage V1, the power supply voltage Vc between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor R1, the return wire resistance value of the return wire, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range is obtained.

[0026] It is important to note that in this embodiment, the grounding wire specifically refers to the line used to achieve grounding connections between multiple electrical devices. Therefore, the first end of the grounding wire is electrically connected to the first electrical device and the first grounding system, respectively, and the second end of the grounding wire is electrically connected to the second electrical device and the second grounding system, respectively. Since the first grounding system and the second grounding system may be different grounding systems, the impedance between the first grounding system and the second grounding system must also be considered. Because the impedance between the first grounding system and the second grounding system is determined by many factors, a fixed value cannot be directly determined in this embodiment. However, its possible values ​​can be considered based on the characteristics of the grounding system, thereby determining the corresponding equivalent resistance range.

[0027] In a power distribution system scenario, the first power equipment can refer to the upstream distribution box, and the second power equipment can refer to the downstream distribution box.

[0028] Specifically, the impedance of the grounding wire is equivalent to a resistance R. PE resistance R PE The resistance value is the grounding wire resistance value. The impedance between the first grounding system and the second grounding system is equivalent to a resistance R. G resistance R G Since the resistance value is within the equivalent resistance range mentioned above, the impedance of the regression line can be equivalent to a resistance R. PEH resistance R PEH The resistance value is the regression line resistance value, from which we can obtain... Figure 3 The equivalent circuit shown is shown.

[0029] Among them, reference Figure 3 resistance R PE and resistance RG After being connected in parallel, it is connected to the measuring resistor R and the resistor R PEH In series, the currents in the series circuit are equal, from which equations (1) and (2) can be obtained.

[0030] (1) (2) in, Indicates parallel connection, Given the current in the series circuit, further, based on equations (1) and (2), equation (3) can be obtained.

[0031] (3) By transforming equation (3), we can obtain equation (4).

[0032] (4) To account for all possible impedances between the first and second grounding systems as much as possible, the resistance R can be determined. G The corresponding equivalent resistance range is (0, +∞). Based on the properties of parallel resistance, we can obtain equation (5).

[0033] (5) At this point, a constant K can be set, where K represents the impedance ratio between the regression line and the grounding line when the grounding line has good performance. Thus, by combining equations (4) and (5), equation (6) can be obtained.

[0034] (6) It should be noted that although a constant K is introduced in equation (6) to represent the impedance ratio between the regression line and the grounding line when the grounding line performance is good, the actual performance of the grounding line will exhibit different impedances, thus affecting the value of the line voltage V1. Ultimately, the range of the grounding line resistance value obtained is related to its own performance. At this time, the range of the grounding line resistance value is: At this point, K can determine the size of the range of grounding wire resistance. Since K is part of the denominator in equation (6), the larger K is, the smaller the range of grounding wire resistance.

[0035] The constant K mentioned above can be determined by selecting the material of the regression line. For example, the regression line can be made of the same material as the grounding wire, and the resistance of the cable can be calculated as shown in equation (7).

[0036] (7) in, Resistivity (unit: Ω) m, Ohm The cable length (in meters) is related to the material and temperature; L represents the cable length (in meters); S represents the cable cross-sectional area (in mm²). 2 (square millimeters). If the material and length of the regression line are the same as those of the grounding wire, then based on equation (6), the impedance relationship between the regression line and the grounding wire can be obtained as follows: ,at this time This refers to the constant K mentioned above.

[0037] Regarding the selection of the resistance value of the measuring resistor R1: The measuring resistor R1 serves both as a voltage divider and a current limiter in the series circuit, ensuring that the current I in the series circuit does not exceed the upper limit of the "safe current". This has already been mentioned above. The total resistance in the series circuit is Considering extreme cases It may be zero. If the upper limit of the "safe current" is 50mA, then the range of the resistance value of the measuring resistor R1 is [Vc / 50mA, +∞).

[0038] Understandably, the resistance value of the measuring resistor R1 directly affects the magnitude of the line voltage V1. Therefore, this factor must be considered when selecting the resistance value of the measuring resistor R1 to determine a more suitable value. When the resistance value of the measuring resistor R1 is large, a resistor connected in series with the regression line can be added to increase the baseline value of the line voltage V1 and reduce the difficulty of obtaining basic data.

[0039] The aforementioned grounding wire detection device is configured with a power supply module, a measuring resistor, a return line, and a control module for grounding wires used to electrically connect multiple electrical devices. The control module can obtain the grounding wire resistance range based on the line voltage between the first end of the grounding wire and the first end of the return line, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first and second grounding systems. Since the equivalent resistance between the first and second grounding systems varies depending on the actual situation, the equivalent resistance range is used to consider its possible values, and a corresponding grounding wire resistance range is determined for each grounding wire. Although the final detected impedance of the grounding wire is expressed as a grounding wire resistance range, the grounding wire resistance range exhibited by the grounding wire under different performance states also differs. Therefore, performance testing can be achieved based on the grounding wire resistance range. This application eliminates the need for current detection of the grounding wire, effectively avoiding the inability to obtain a stable and accurate current due to interference from induced current in the circuit and the accuracy issues of the current transformer, ultimately improving the reliability of the entire impedance detection.

[0040] like Figure 2 As shown, in one embodiment, the control module is also electrically connected to the power supply module.

[0041] The control module is used to control the power module to output different power supply voltages, thereby obtaining the grounding wire resistance range corresponding to each power supply voltage.

[0042] In practice, when testing the grounding wire, there may be detection errors due to interference. To improve the testing results, multiple tests can be performed. To eliminate errors caused by the power supply voltage, different power supply voltages can be used for each test.

[0043] like Figure 4 As shown, in one embodiment, the measuring resistor R1 is an adjustable resistor electrically connected to the control module.

[0044] The control module is used to control the measuring resistor R1 to provide different measuring resistance values, thereby obtaining the grounding wire resistance range corresponding to each measuring resistance value.

[0045] In this embodiment, the control module controls the power supply module to output different power supply voltages. In order to eliminate the related errors caused by the measured resistance value, different measured resistance values ​​are used for multiple tests.

[0046] In other embodiments, the control module can simultaneously control the power module to output different power supply voltages and control the measuring resistor to provide different measuring resistance values. In this case, a power supply voltage and a measuring resistance value constitute a parameter group, thereby obtaining the grounding wire resistance value range corresponding to each parameter group.

[0047] Understandably, in Figure 4 In this diagram, to demonstrate that the resistance value of the measuring resistor R1 is adjustable, it is drawn as an adjustable resistor and is electrically connected to the control module. This is merely to show that the control module can control the measuring resistor R1 to provide different measured resistance values. In practice, the control module can control the measuring resistor R1 through related structures, such as motors.

[0048] Secondly, the present invention provides a method for detecting a grounding wire, which is applied to the grounding wire detection device in any of the above embodiments, with reference to... Figure 1 , Figure 2 and Figure 3 The grounding wire detection method includes the following steps performed by the control module: The line voltage V1 between the first end of the grounding wire and the first end of the return line is detected. Based on the line voltage V1, the power supply voltage Vc between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor R1, and the return line resistance value (i.e., resistance R) of the return line... PEHThe resistance value) and the equivalent resistance range between the first grounding system and the second grounding system (i.e., resistance R) G Possible values), to obtain the range of grounding wire resistance (i.e., resistance R) PE Possible values).

[0049] The specific calculation process for the resistance range of the grounding wire can be referred to in the embodiment of the grounding wire detection device described above, and will not be repeated here.

[0050] The grounding wire detection device used in the above-described grounding wire detection method is configured with a power supply module, a measuring resistor, a return line, and a control module for grounding wires used to electrically connect multiple electrical devices. The control module can obtain the grounding wire resistance range based on the line voltage between the first end of the grounding wire and the first end of the return line, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first and second grounding systems. Since the equivalent resistance between the first and second grounding systems may vary depending on the actual situation, the equivalent resistance range is used to consider its possible values, and a corresponding grounding wire resistance range is determined for each grounding wire. Although the final detected impedance of the grounding wire is expressed as a grounding wire resistance range, the grounding wire resistance range exhibited by the grounding wire under different performance states is also different. Therefore, performance detection can be achieved based on the grounding wire resistance range. This application eliminates the need for current detection of the grounding wire, effectively avoiding the inability to obtain a stable and accurate current due to interference from induced current in the circuit and the accuracy problems of the current transformer, ultimately improving the reliability of the entire impedance detection.

[0051] In one embodiment, after obtaining the grounding wire resistance range, the grounding wire detection method further includes the following steps performed by the control module: The performance test results of the grounding wire are obtained based on the grounding wire resistance range and the preset standard grounding wire resistance value.

[0052] As mentioned in the above embodiments, the grounding wire will exhibit different impedances and different resistance ranges under different performance conditions. This resistance range is determined based on the equivalent resistance range between the first and second grounding systems, with the minimum and maximum values ​​that may exist between the first and second grounding systems as the endpoints.

[0053] Therefore, when the grounding wire performs well, the corresponding grounding wire resistance range should be extended upwards and downwards based on the preset standard grounding wire resistance value. In other words, the preset standard grounding wire resistance value should be located at the center of the grounding wire resistance range, so that the performance test result of the grounding wire can be determined based on the positional relationship between the preset standard grounding wire resistance value and the grounding wire resistance range.

[0054] Specifically, as mentioned in the above embodiments, the grounding wire resistance range is... The preset standard grounding wire resistance value can be obtained based on the distance between the first and second power devices and according to cable standards, and can be set to R. 标准 Simplifying the grounding wire resistance range, we obtain a simplified grounding wire resistance range (min, max). When the grounding wire performs well, R can be obtained. 标准 The positional relationship with (min, max) is as follows: Figure 5 As shown.

[0055] In one embodiment, the performance test results of the grounding wire are obtained based on the grounding wire resistance range and a preset standard grounding wire resistance value, including: The preset standard grounding wire resistance value is matched within the grounding wire resistance value range to obtain the matching result.

[0056] If the matching result indicates that the preset standard grounding wire resistance value is within the grounding wire resistance value range, then the first performance test result of the grounding wire is obtained.

[0057] If the matching result indicates that the preset standard grounding wire resistance value is outside the grounding wire resistance value range, then the second performance test result of the grounding wire is obtained.

[0058] Specifically, the grounding wire resistance range is divided into multiple candidate intervals distributed sequentially, such as... Figure 5 As shown, the total width of the grounding wire resistance range is H, where H = max - min. Therefore, the multiple candidate intervals include [0, min], (min, min + 0.10H), [min + 0.10H, min + 0.25H), [min + 0.25H, max - 0.25H], (max - 0.25H, max - 0.10H), (max - 0.10H, max), and [max, +∞], corresponding to the performance levels of fault, potential hazard, normal, good, normal, potential hazard, and fault, respectively. See Table 1 for details.

[0059]

[0060] Taking a distribution box as an example: Good: The grounding wire connection between the two-level distribution boxes is secure and the operation is good.

[0061] Normal: The grounding wire connection between the two-level distribution boxes is normal, and the operation is normal.

[0062] Potential hazard: There is a potential hazard in the grounding wire connection between the two-level distribution boxes. Repair should be carried out if possible. If not, daily inspections should be strengthened.

[0063] Fault: There is a grounding wire connection fault between the two-level distribution boxes. Please arrange for personnel to inspect and repair immediately.

[0064] If the matching result indicates that the preset standard grounding wire resistance value is within the average resistance value range, then the target candidate interval corresponding to the preset standard grounding wire resistance value is determined in the grounding wire resistance value range. Based on the distribution position of the target candidate interval in the grounding wire resistance value range, the first performance test result corresponding to the target candidate interval is obtained.

[0065] Among them, such as Figure 5 As shown, the target selection interval is [min+0.25H, max-0.25H], which is located in the middle 50% of the grounding wire resistance range. Therefore, a first performance test result characterizing good grounding wire performance can be obtained. In other examples, first performance test results characterizing potential grounding wire performance defects or normal performance can also be obtained.

[0066] It is understandable that (min, min+0.10H), [min+0.10H, min+0.25H), [min+0.25H, max-0.25H], (max-0.25H, max-0.10H), and (max-0.10H, max) are all within the grounding wire resistance range, corresponding to performance characteristics including potential problems, normal operation, and good performance. Therefore, the first performance test result can characterize potential problems, normal operation, or good performance. However, [0, min] and [max, +∞] are outside the grounding wire resistance range, corresponding to performance characteristics of faults. Therefore, in addition to obtaining the first performance test result, a second performance test result characterizing a fault can also be obtained.

[0067] In one embodiment, refer to Figure 2 The control module is also electrically connected to the power supply module; it detects the line voltage between the first end of the grounding wire and the first end of the return wire, and obtains the grounding wire resistance range based on the line voltage, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return wire resistance value of the return wire, and the equivalent resistance range between the first grounding system and the second grounding system. This range includes: The control power module outputs different power voltages and detects the line voltage corresponding to each power voltage. Understandably, after the control module controls the power module to output a power supply voltage, it detects the line voltage corresponding to that power supply voltage, and then controls the power module to output the next power supply voltage, and so on.

[0068] For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the corresponding power supply voltage, the measured resistance, the regression line resistance, and the equivalent resistance range.

[0069] When multiple grounding wire resistance ranges are detected, one can be selected as the final grounding wire resistance range, and subsequent performance testing can be carried out based on the selected grounding wire resistance range.

[0070] In one embodiment, refer to Figure 4 The measuring resistor is an adjustable resistor and electrically connected to the control module; the line voltage between the first end of the grounding wire and the first end of the return line is detected; based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range is obtained, including: The control resistors provide different measured resistance values ​​and detect the line voltage corresponding to each measured resistance value.

[0071] Understandably, after the control module controls the measuring resistor to provide a measured resistance value, it detects the line voltage corresponding to the power supply voltage, and then controls the measuring resistor to provide the next measured resistance value, and so on.

[0072] For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the power supply voltage, the measured resistance value corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

[0073] When multiple grounding wire resistance ranges are detected, one can be selected as the final grounding wire resistance range, and subsequent performance testing can be carried out based on the selected grounding wire resistance range.

[0074] In one embodiment, while referring to Figure 2 and Figure 4 The control module is also electrically connected to the power module, and the measuring resistor is an adjustable resistor also electrically connected to the control module. It detects the line voltage between the first end of the grounding wire and the first end of the return line. Based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first and second grounding systems, the grounding wire resistance range is obtained, including: The control power module outputs different power supply voltages and controls the measuring resistors to provide different measured resistance values. Each power supply voltage and each measured resistance value constitutes a parameter group.

[0075] The line voltage corresponding to each parameter group is detected separately.

[0076] Understandably, after the control module controls the power module to output a power supply voltage and controls the measuring resistor to provide a measurement resistance value, it detects the line voltage corresponding to that power supply voltage, and then controls the power module to output the next power supply voltage and controls the measuring resistor to provide the next measurement resistance value, and so on.

[0077] For each line voltage, the range of grounding wire resistance corresponding to that line voltage is obtained based on the line voltage, the parameter set corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

[0078] When multiple grounding wire resistance ranges are detected, one can be selected as the final grounding wire resistance range, and subsequent performance testing can be carried out based on the selected grounding wire resistance range.

[0079] The above embodiments illustrate schemes for detecting multiple grounding wire resistance ranges based on multiple power supply voltages, multiple measured resistance values, and multiple parameter sets. The premise for achieving this is that multiple power supply voltages, multiple measured resistance values, and multiple parameter sets need to be determined in advance.

[0080] Specifically, a loop can be pre-built based on a standard grounding wire. After the loop is built, the power module can be controlled to output a large number of power supply voltages and / or the measuring resistor can be controlled to provide a large number of measuring resistance values. Then, a large number of standard grounding wire resistance value ranges are detected. Next, the multiple standard grounding wire resistance value ranges are averaged to obtain the average standard grounding wire resistance value range. Finally, the power supply voltage and / or measuring resistance values ​​corresponding to the multiple (e.g., three) standard grounding wire resistance value ranges closest to the average standard grounding wire resistance value range are selected.

[0081] In one embodiment, after the step of obtaining the grounding wire resistance range corresponding to each line voltage based on the line voltage, the parameter set corresponding to the line voltage, the regression line resistance value, and the equivalent resistance range, the grounding wire detection method further includes the following steps performed by the control module: Determine the average resistance range among multiple grounding wire resistance ranges; The performance test results of the grounding wire are obtained based on the average resistance range and the preset standard grounding wire resistance.

[0082] In this embodiment, since multiple grounding wire resistance ranges are detected, the average resistance range can be obtained by averaging, and the performance test result of the grounding wire is finally determined based on the positional relationship between the average resistance range and the preset standard grounding wire resistance value.

[0083] In one embodiment, the performance test results of the grounding wire are obtained based on the average resistance range and a preset standard grounding wire resistance value, including: The preset standard grounding wire resistance value is matched within the average resistance range to obtain the matching result; If the matching result indicates that the preset standard grounding wire resistance is within the average resistance range, then the first performance test result of the grounding wire is obtained.

[0084] Specifically, the average resistance range is divided into multiple candidate intervals distributed sequentially; if the matching result indicates that the preset standard grounding wire resistance is within the average resistance range, then the first performance test result of the grounding wire is obtained, including: If the matching result indicates that the preset standard grounding wire resistance value is within the average resistance range, then the target candidate interval corresponding to the preset standard grounding wire resistance value within the average resistance range is determined.

[0085] Based on the distribution of the target candidate interval within the average resistance range, the first performance test result corresponding to the target candidate interval is obtained.

[0086] If the matching result indicates that the preset standard grounding wire resistance value is outside the average resistance range, then the second performance test result of the grounding wire is obtained.

[0087] The performance testing process after obtaining the average resistance range is the same as the performance testing process based on the resistance range of a single grounding wire, and will not be repeated here.

[0088] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the detailed descriptions of other embodiments above, which will not be repeated here.

[0089] The above provides a detailed description of the grounding wire detection device and grounding wire detection method provided by the present invention. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

[0090] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A grounding wire detection device, characterized in that, The grounding wire detection device includes a power module, a measuring resistor, a return line, and a control module; The positive terminal of the power module is used to be electrically connected to the first end of the grounding wire and the first grounding system through the measuring resistor, the negative terminal of the power module is electrically connected to the first end of the regression line, and the second end of the regression line is used to be electrically connected to the second end of the grounding wire and the second grounding system. The control module is used to detect the line voltage between the first end of the grounding wire and the first end of the return line, and to obtain the grounding wire resistance range of the grounding wire based on the line voltage, the power supply voltage between the positive and negative terminals of the power supply module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system.

2. The grounding wire detection device according to claim 1, characterized in that, The control module is also electrically connected to the power module; The control module is used to control the power module to output different power supply voltages, thereby obtaining the grounding wire resistance range corresponding to each power supply voltage.

3. The grounding wire detection device according to claim 1, characterized in that, The measuring resistor is an adjustable resistor and is electrically connected to the control module; The control module is used to control the measuring resistor to provide different measuring resistance values, thereby obtaining the grounding wire resistance range corresponding to each measuring resistance value.

4. A method for detecting a grounding wire, characterized in that, The grounding wire detection method is applied to the grounding wire detection device according to any one of claims 1 to 3, and the grounding wire detection method includes the following steps executed by the control module: The line voltage between the first end of the grounding wire and the first end of the return line is detected. Based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance of the measuring resistor, the return line resistance of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, the grounding wire resistance range of the grounding wire is obtained.

5. The grounding wire detection method according to claim 4, characterized in that, The control module is also electrically connected to the power module; the detection module detects the line voltage between the first end of the grounding wire and the first end of the return line, and obtains the grounding wire resistance range of the grounding wire based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, including: The power module is controlled to output different power voltages and the line voltage corresponding to each power voltage is detected. For each line voltage, the grounding wire resistance range corresponding to that line voltage is obtained based on the line voltage, the power supply voltage corresponding to that line voltage, the measured resistance value, the regression line resistance value, and the equivalent resistance range.

6. The grounding wire detection method according to claim 4, characterized in that, The measuring resistor is an adjustable resistor and is electrically connected to the control module; the line voltage between the first end of the grounding wire and the first end of the return line is detected, and the grounding wire resistance range of the grounding wire is obtained based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, including: The measuring resistors are controlled to provide different measuring resistance values, and the line voltage corresponding to each measuring resistance value is detected respectively; For each line voltage, the grounding wire resistance range corresponding to that line voltage is obtained based on the line voltage, the power supply voltage, the measured resistance value corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

7. The grounding wire detection method according to claim 4, characterized in that, The control module is also electrically connected to the power module, and the measuring resistor is an adjustable resistor and electrically connected to the control module; the detection of the line voltage between the first end of the grounding wire and the first end of the return line, and the determination of the grounding wire resistance range based on the line voltage, the power supply voltage between the positive and negative terminals of the power module, the measured resistance value of the measuring resistor, the return line resistance value of the return line, and the equivalent resistance range between the first grounding system and the second grounding system, includes: The power module is controlled to output different power voltages and the measuring resistor is controlled to provide different measuring resistance values. A power voltage and a measuring resistance value constitute a parameter group. Detect the line voltage corresponding to each parameter group separately; For each line voltage, the grounding wire resistance range corresponding to that line voltage is obtained based on the line voltage, the parameter group corresponding to that line voltage, the regression line resistance value, and the equivalent resistance range.

8. The method for detecting a grounding wire according to any one of claims 5 to 7, characterized in that, After the step of obtaining the grounding wire resistance range corresponding to each line voltage based on the line voltage, the parameter group corresponding to the line voltage, the regression line resistance value, and the equivalent resistance range, the grounding wire detection method further includes the following steps executed by the control module: Determine the average resistance range among multiple grounding wire resistance ranges; The performance test results of the grounding wire are obtained based on the average resistance range and the preset standard grounding wire resistance.

9. The method for detecting grounding wires according to claim 8, characterized in that, The process of obtaining the performance test results of the grounding wire based on the average resistance range and the preset standard grounding wire resistance includes: The preset standard grounding wire resistance value is matched within the average resistance range to obtain a matching result; If the matching result indicates that the resistance value of the preset standard grounding wire is within the average resistance range, then the first performance test result of the grounding wire is obtained. If the matching result indicates that the preset standard grounding wire resistance is outside the average resistance range, then the second performance test result of the grounding wire is obtained.

10. The method for detecting grounding wires according to claim 9, characterized in that, The average resistance range is divided into multiple candidate intervals distributed sequentially; If the matching result indicates that the preset standard grounding wire resistance is within the average resistance range, then the first performance test result of the grounding wire is obtained, including: If the matching result indicates that the preset standard grounding wire resistance value is within the average resistance value range, then the target candidate interval corresponding to the preset standard grounding wire resistance value in the average resistance value range is determined. Based on the distribution position of the target candidate interval within the average resistance range, a first performance test result corresponding to the target candidate interval is obtained.

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