An online automatic test method for resistance value of grounding device in gas station

Abstract

The invention discloses an online automatic test method for the resistance of a grounding device of a gas station, and relates to the technical field of resistance test of lightning protection and antistatic grounding devices of gas stations and oil depots. A grounding resistance tester that meets the requirements and has a test accuracy of 0.1 ohm is selected, the grounding resistance tester is provided with a switch, the grounding resistance tester uses a three-wire test principle, and is equipped with an LED display screen and a disposable battery for power supply. A bull nose connector is installed on a test line and an auxiliary grounding line of the tester, and is fixed to a test point and an auxiliary grounding electrode by screws. An RS485 networking device is connected to the grounding resistance tester, a multi-channel resistance collector is installed in the gas station, and is connected to the RS485 networking device of the tester through an RS485 interface, and the multi-channel resistance collector is connected to a computer of the gas station through the RS485 interface. After a correction process to eliminate the influence of environmental factors is performed through a data processing module, a stability evaluation is performed to judge whether the feedback grounding device is in a stable state.

Description

Technical Field

[0001] The invention relates to the technical field of resistance value testing of lightning protection and antistatic grounding devices of gas stations and oil depots, and in particular to an online automatic resistance value testing method of a grounding device of a gas station. Background Art

[0002] At present, each gas station has more than 10 gas pumps on average. The ground resistance of each gas pump must be tested at regular intervals. Professional technicians are sent to use professional ground resistance testers for each test. On average, each gas station takes about 2 hours to test. Gas stations are far away, and only a few can be tested in a day, which affects the detection efficiency.

[0003] Taking Gansu Province as an example, there are more than 1,000 gas stations. It takes one year to test each gas station, and the cost of two people per year is required, including travel expenses of about 200,000 yuan per year. Therefore, the current pain point of testing the grounding resistance of gas stations is that it requires professionals to run to each gas station, which is time-consuming, labor-intensive, and inefficient. On average, each gas station can only be tested once a year; since the test is carried out regularly, it is impossible to obtain the status information of the grounding device in real time; in the time period between two tests, if there is a problem with the grounding device, it cannot be discovered and handled in time, increasing safety hazards; in addition, manual testing requires manual recording of data, and subsequent sorting and analysis. This process is cumbersome and error-prone, and is not conducive to the long-term preservation and traceability of data; and the measurement results of grounding resistance are affected by various environmental factors, such as temperature, humidity, and soil resistivity. The existing technology often lacks real-time monitoring and correction of these environmental factors, resulting in a certain impact on the accuracy of the measurement results. Summary of the invention

[0004] The purpose of the present invention is to provide an online automatic test method for the resistance of a gas station grounding device, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution, and the specific test steps of the online automatic resistance test method are as follows:

[0006] 1. Test equipment installation and configuration preparation

[0007] S1. Select a ground resistance tester that meets the requirements and has a test accuracy of 0.1 ohm. The ground resistance tester has a switch, uses the three-wire test principle, and is equipped with an LED display screen and disposable battery power supply;

[0008] S2. Install the bull nose connector on the test line and auxiliary grounding wire of the tester, and fix it on the test point and auxiliary grounding electrode with screws;

[0009] S3. Connect the RS485 networking device to the ground resistance tester;

[0010] S4. Install a multi-channel resistance collector in the gas station and connect it to the RS485 networking device of the tester through the RS485 interface;

[0011] S5. Connect the multi-channel resistance collector to the computer at the gas station through the RS485 interface and upload the data to the computer in real time;

[0012] S6. Check that the gas station's computers are connected to the Internet and that data can be aggregated to the company's headquarters; 2. Test equipment to obtain calibration and evaluation feedback

[0013] Data acquisition, the real-time collected resistance data is transmitted to the multi-channel resistance collector through the measurement and detection module of the RS485 networking device;

[0014] Data correction processing: After the continuously collected resistance data is corrected to eliminate the influence of environmental factors through the data processing module, stability evaluation is performed to determine whether the feedback grounding device is in a stable state. The data processing module includes a real-time data measurement and acquisition unit, a comprehensive environmental temperature and humidity parameter correction unit, and a dynamic stability evaluation and loop feedback unit;

[0015] Data upload: record the collected resistance data, the results of each test and the alarm information on the computer at the company headquarters and generate a detailed test report;

[0016] The equipment used by the measurement and detection module includes a high-precision ground resistance tester and an environmental sensor, and the equipment used by the data processing module includes a data transmission device, a computer, and an embedded processing system.

[0017] Optionally, the calculation formula of the real-time data measurement and acquisition unit is as follows:

[0018] D 1(t) =Y AB(t) / H AB ;

[0019] in:

[0020] D 1(t) is the foundation grounding resistance value at time t;

[0021] Y AB(t) is the voltage difference between AB at time t, H AB A constant current value is injected between AB, A is the test voltage pole, B is the test current pole, and it is obtained through the RS485 networking device.

[0022] Optionally, the calculation formula of the comprehensive environmental temperature and humidity parameter correction unit is as follows:

[0023] D 2(t) =D 1(t) *(WJZ+SJZ);

[0024] WJZ=1+a*(W (t) -CW);

[0025] SJZ=b*(S (t) -CS) / 100;

[0026] in:

[0027] D 2(t) is the resistance value after correction at time t;

[0028] WJZ is the temperature correction factor;

[0029] a is the temperature coefficient;

[0030] W (t) is the temperature value at time t;

[0031] CW is the reference temperature value;

[0032] SJZ is the humidity correction factor;

[0033] b is the humidity influence coefficient;

[0034] S (t) is the relative humidity value at time t;

[0035] CS is the reference relative humidity value.

[0036] Optionally, the calculation formula of the dynamic stability evaluation and loop feedback unit is as follows:

[0037]

[0038]

[0039] XC=c*(D 3(t-1) -D 2(t) ) 2 ;

[0040] in:

[0041] D 3(t) is the resistance value after stable evaluation within time t;

[0042] γ is the weight coefficient;

[0043] D 2(t-1) is the resistance value after correction at time t-1;

[0044] PD 2(t-1)is the average value of the corrected resistance before time t-1, C is the total number of detections, k is the time window width, D 2i is the square value of the i-th grounding resistance;

[0045] XC is the dynamic adjustment value;

[0046] c is the loop feedback coefficient;

[0047] D 3(t-1) is the internal resistance evaluation value at time t-1.

[0048] Optionally, the feedback evaluation based on the detection changes of the comprehensive environmental temperature and humidity parameter correction unit and the dynamic stability evaluation and loop feedback unit is as follows:

[0049] S1, set the resistance value D after correction within time t 2(t) As the main evaluation value of the test, set the internal resistance evaluation value D at time t-1 3(t-1) The safety assessment value of the test is set to the dangerous resistance threshold D4 as the dangerous assessment value of the test;

[0050] S2, if the resistance value after correction within time t is D 2(t) Exceeding the resistance evaluation value D at time t-1 3(t-1) , and the dangerous resistance threshold D4 is not reached, the feedback enters the early warning interval. At this time, the system issues a warning to prompt the operator to pay attention to the status of the grounding system and to check and monitor it;

[0051] S3, if the resistance value after correction within time t is D 2(t) If the resistance exceeds the dangerous resistance threshold D4, it is considered that there is a serious problem with the grounding system or the environmental factors have changed dramatically. At this time, the system should immediately issue an emergency alarm and take emergency response measures;

[0052] S4, if the resistance value after correction within time t is D 2(t) The internal resistance evaluation value D at time t-1 3(t-1) If they are close to each other, it is considered to be normal fluctuation.

[0053] Optionally, the dynamic adjustment value plays a role of dynamic adjustment in the dynamic stability evaluation and loop feedback unit. When the difference term is large, the result value of the resistance value after stable evaluation within time t will be increased, thereby reflecting the instability of the resistance value.

[0054] Optionally, the test accuracy of the ground resistance tester reaches 0.1 ohm. When the resistance of the gas station is less than 10 ohms, it is considered qualified. If it is unqualified, it will be reported immediately to the headquarters to send professionals to check the grounding system. The LED display screen can directly display the ground resistance value within a few seconds after each startup.

[0055] Optionally, the shell of the ground resistance tester is of explosion-proof type. When testing, the ground resistance tester fluctuates to the power-on position to connect the wires for testing, and after the test, it fluctuates to the power-off position to cut off the wires and shut down.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] 1. The present invention can realize real-time and rapid detection of the ground resistance of all gas pumps in a gas station through online automated testing, which greatly shortens the detection time. At the same time, since there is no need for manual on-site operation, technicians can remotely monitor and manage multiple gas stations. Each time a test is performed, the ground resistance data of the gas pump can be displayed by turning on the switch of the ground resistance tester. In this way, each test of a gas station only takes a few minutes to complete, and there is no need to specially send professional technicians to each gas station for testing. Any local employee of the gas station can complete the test, thereby significantly improving the test efficiency.

[0058] 2. The present invention reduces the reliance on professional technicians and reduces labor costs through automated testing. Technicians can view and manage the status of the grounding devices of each gas station through a computer in the office without having to frequently travel between gas stations, thus achieving the convenient effect of automated testing.

[0059] 3. The present invention can obtain the status information of the grounding device in real time and report it immediately once an abnormality is found, thereby ensuring timely discovery and handling of problems, reducing safety hazards and enhancing the real-time nature of the test.

[0060] Fourth, the present invention utilizes an automated test system to automatically record and save test data without manual intervention. At the same time, the system can also automatically analyze and process the data and generate a detailed test report to facilitate subsequent data tracing and analysis.

[0061] 5. The present invention can eliminate the influence of environmental factors on the ground resistance measurement results and improve the measurement accuracy through the correction of the comprehensive environmental temperature and humidity parameter correction unit. At the same time, the evaluation and feedback of the dynamic stability evaluation and loop feedback unit can further ensure the stability and reliability of the measurement results and improve the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A flow chart of the preparation of the test equipment installation and configuration for the online automated test method of the resistance of the grounding device of the gas station;

[0063] Figure 2 This is a schematic diagram of the workflow of the automated testing method;

[0064] Figure 3 It is a test flow diagram of the online automatic test method for the resistance of the grounding device of a gas station according to the present invention;

[0065] Figure 4 It is a structural schematic diagram of the data processing module of the present invention. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] Regarding the online automated testing method for the resistance of the grounding device of a gas station, it is different from the existing online automated testing method for the resistance of the grounding device of a gas station. The existing ground resistance of each gas pump in the resistance test of the grounding device of a gas station needs to be tested separately, and its gas stations are widely distributed, which makes the entire testing process time-consuming, which not only increases the labor cost, but also greatly affects the detection efficiency. In addition, the process of manually recording the detection data is cumbersome and prone to errors. In addition, since the detection is carried out regularly, the status information of the grounding device cannot be obtained in real time. Finally, the existing technology often lacks real-time monitoring and correction of these environmental factors, which causes the accuracy of the measurement results to be affected to a certain extent. The algorithm unit comprehensively optimizes and solves the shortcomings of the existing technology by improving detection efficiency, saving human resources, enhancing real-time performance, facilitating data recording and analysis, and improving measurement accuracy.

[0068] For example, see Figures 1 to 4 This embodiment provides an online automatic test method for the resistance of a gas station grounding device. The specific test steps of the online automatic test method for resistance are as follows:

[0069] 1. Test equipment installation and configuration preparation

[0070] S1. Select a ground resistance tester that meets the requirements and has a test accuracy of 0.1 ohm. The ground resistance tester has a switch, uses the three-wire test principle, and is equipped with an LED display screen and disposable battery power supply;

[0071] S2. Install the bull nose connector on the test line and auxiliary grounding wire of the tester, and fix it on the test point and auxiliary grounding electrode with screws;

[0072] S3. Connect the RS485 networking device to the ground resistance tester;

[0073] S4. Install a multi-channel resistance collector in the gas station and connect it to the RS485 networking device of the tester through the RS485 interface;

[0074] S5. Connect the multi-channel resistance collector to the computer at the gas station through the RS485 interface and upload the data to the computer in real time;

[0075] S6. Check that the gas station's computers are connected to the Internet and that data can be aggregated to the company's headquarters; 3. Test equipment to obtain calibration and evaluation feedback

[0076] Data acquisition, the real-time collected resistance data is transmitted to the multi-channel resistance collector through the measurement and detection module of the RS485 networking device;

[0077] Data correction processing: Through the data processing module, the continuously collected resistance data is corrected to eliminate the influence of environmental factors, and then stability evaluation is performed to determine whether the feedback grounding device is in a stable state. The data processing module includes a real-time data measurement and acquisition unit, a comprehensive environmental temperature and humidity parameter correction unit, and a dynamic stability evaluation and loop feedback unit;

[0078] Data upload: record the collected resistance data, the results of each test and the alarm information on the computer at the company headquarters and generate a detailed test report;

[0079] The equipment used in the measurement and detection module includes a high-precision ground resistance tester and an environmental sensor, and the equipment used in the data processing module includes data transmission equipment, a computer, and an embedded processing system.

[0080] In this embodiment, the ground resistance tester is installed on the grounding flat iron of the gas pump. By adding RS485 networking equipment, the data is directly connected to the multi-channel resistance collector of the local gas station through the RS485 sensor. The multi-channel resistance collector can be connected to the computer of the gas station through RS485. The computer of the gas station is connected to the Internet, and the data can be directly summarized to the company headquarters. This equipment can greatly improve the frequency and efficiency of ground resistance testing. For example, the test can be changed from once a year to once or twice a month, which is much higher than the original test frequency, greatly improving the safety detection level of the gas station grounding system and the safety performance of the gas station. Not only can the test frequency be more, but also faster. The data can be uploaded directly to the Internet, and the test results can be directly displayed at the headquarters, completely saving professional testers and travel expenses.

[0081] In this embodiment, the system uses the cooperation of three algorithm units to automatically test the resistance of the grounding device at the gas station. 1(t) , D 2(t) and D 3(t) The three calculation results can form a digital, networked, and big data resistance test, which is a new direction for technological innovation in ground resistance testing and also represents a new direction for the future development of ground resistance testing. 1(t)The core of the test is to realize the basic measurement of the resistance of the gas station grounding device and ensure that these measurement data can be obtained in real time and accurately. This is the cornerstone of the entire online automatic test system and provides the original basis for subsequent data processing and analysis. 2(t) is the corrected resistance value within time t. The basic resistance measurement result is corrected by environmental parameters. Since the measurement result of ground resistance is affected by many environmental factors, including temperature, humidity, and soil resistivity, it is necessary to improve the accuracy and reliability of the measurement result by correcting the comprehensive environmental parameters. 3(t) The resistance value after stable evaluation within time t is designed to monitor the change trend of the resistance value of the grounding device through dynamic stability evaluation, and timely adjust the test strategy or issue an early warning signal through a loop feedback mechanism. This step is the key to ensure the long-term stable operation of the grounding device. 3(t) Based on D 1(t) and D 2(t) It is obtained by comprehensive evaluation, which reflects the stability and dynamic change process of the grounding resistance value. This evaluation result is important for D 1(t) There is no direct feedback effect because D 1(t) is calculated based on real-time measurement data, however, D 3(t) It can be used as a basis for system status assessment and to guide subsequent monitoring and maintenance work, so that the overall algorithm system can perform automated feedback and optimization based on actual conditions to be closer to reality.

[0082] See also Figures 1 to 4 , the calculation formula of the real-time data measurement acquisition unit is as follows:

[0083] D 1(t) =Y AB(t) / H AB ;

[0084] in:

[0085] D 1(t) is the foundation grounding resistance value at time t;

[0086] Y AB(t) is the voltage difference between AB at time t, H AB A constant current value is injected between AB, A is the test voltage pole, B is the test current pole, and it is obtained through the RS485 networking device.

[0087] In this embodiment: First, in this algorithm unit, Y AB(t)Y is the voltage difference between AB at time t, which is measured by a voltage sensor installed on the grounding system. The sensor is connected to the data acquisition system through an RS485 networking device. During the measurement process, the voltage sensor will detect the potential difference between the test voltage electrode A and the test current electrode B in real time, and transmit this voltage value to the data acquisition system through the RS485 interface. The data acquisition system will record this voltage value at each sampling time t, that is, Y AB(t) ;H AB A constant current value is injected between AB. This is a known constant current value, usually provided by the current source inside the ground resistance tester. Before the test starts, the tester will inject this constant current between A and B to generate a measurable voltage difference. This current value remains unchanged during the test, so there is no need for real-time measurement. The division of the two outputs the basic ground resistance value D at the real-time time t. 1(t) .

[0088] This algorithm unit ensures the timeliness of data through real-time measurement of foundation resistance, allowing managers to grasp the status of the grounding device at any time and discover potential problems in a timely manner; the high-precision measurement technology ensures the accuracy of the measurement results and reduces the impact of human errors and interference factors; and the automated measurement process greatly reduces the manual burden, improves work efficiency, and avoids measurement errors caused by human negligence.

[0089] See also Figures 1 to 4 , the calculation formula of the comprehensive environmental temperature and humidity parameter correction unit is as follows:

[0090] D 2(t) =D 1(t) *(WJZ+SJZ);

[0091] WJZ=1+a*(W (t) -CW);

[0092] SJZ=b*(S (t) -CS) / 100;

[0093] in:

[0094] D 2(t) is the resistance value after correction at time t;

[0095] WJZ is the temperature correction factor;

[0096] a is the temperature coefficient;

[0097] W (t) is the temperature value at time t;

[0098] CW is the reference temperature value;

[0099] SJZ is the humidity correction factor;

[0100] b is the humidity influence coefficient;

[0101] S (t) is the relative humidity value at time t;

[0102] CS is the reference relative humidity value.

[0103] In this embodiment, firstly, based on the real-time data measurement acquisition unit output, the foundation ground resistance value D at time t is obtained. 1(t) ; "WJZ=1+a*(W (t) -CW)" calculates the temperature value W at time t (t) The difference between the reference temperature value CW and the correction factor adjusted by the temperature coefficient a, the calculated value is a proportional factor, which is used to adjust the influence of temperature change on the grounding resistance measurement value. When the temperature is higher than the reference temperature, the factor is usually greater than 1, indicating that the resistance value may increase due to the temperature increase. On the contrary, when the temperature is lower than the reference temperature, the factor is less than 1, indicating that the resistance value may decrease due to the temperature decrease. Temperature is one of the important factors affecting the grounding resistance. The resistivity of soil and other materials changes with temperature. Therefore, this correction factor is needed to eliminate the influence of temperature change on the grounding resistance measurement result. By applying this temperature correction factor WJZ, the grounding resistance value measured under different temperature conditions can more accurately reflect the actual state of the grounding device, and improve the accuracy and reliability of the measurement result. "SJZ=b*(S (t) -CS) / 100" calculates the relative humidity value S at time t (t) The difference between the reference relative humidity value CS and the correction factor adjusted by the humidity influence coefficient b reflects the relationship between humidity and grounding resistance. Humidity is another important factor affecting grounding resistance. By applying an appropriate humidity correction factor, the accuracy of grounding resistance measurement results can be further improved, especially in environments with large humidity changes. This helps to ensure that the grounding device can maintain its expected performance and safety under different humidity conditions. According to the basic grounding resistance value D within the above time t 1(t) , temperature correction factor WJZ and humidity correction factor SJZ, output the corrected resistance value D within the corrected time t 2(t) .

[0104] This algorithm unit can eliminate the influence of environmental factors on the ground resistance measurement results and further improve the measurement accuracy by correcting the comprehensive environmental parameters; the correction algorithm enables the test equipment to adapt to the measurement needs under different environmental conditions, improves the versatility and practicality of the equipment, and enhances its adaptability; the corrected measurement data is more reliable, providing strong support for subsequent decision-making and analysis, and can greatly improve the reliability of the data.

[0105] 10. Please refer to Figures 1 to 4 , the calculation formula of the dynamic stability evaluation and loop feedback unit is as follows:

[0106]

[0107]

[0108] XC=c*(D 3(t-1) -D 2(t) ) 2 ;

[0109] in:

[0110] D 3(t) is the resistance value after stable evaluation within time t;

[0111] γ is the weight coefficient;

[0112] D 2(t-1) is the resistance value after correction at time t-1;

[0113] PD 2(t-1) is the average value of the corrected resistance before time t-1, C is the total number of detections, k is the time window width, D 2i is the square value of the i-th grounding resistance;

[0114] XC is the dynamic adjustment value;

[0115] c is the loop feedback coefficient;

[0116] D 3(t-1) is the internal resistance evaluation value at time t-1.

[0117] In this embodiment, the algorithm unit first calculates the average value of the corrected resistance PD before time t-1 2(t-1) is the average value of all R2 measurements within the time window defined before time t-1, and the corrected resistance value D within time t-1 2(t-1) It is the D2 value obtained in the measurement immediately before time t-1. This value is usually obtained directly from the measurement data without additional calculation. In the dynamic stability evaluation, the corrected resistance value D within time t-1 is 2(t-1) and the average resistance value PD after correction before time t-1 2(t-1) It is used to compare the changing trend of ground resistance value in a short time. For example, it can calculate the corrected resistance value D within time t-1. 2(t-1) The average resistance value PD after correction before time t-1 2(t-1) The relative change or percentage change between the two values ​​is used to evaluate whether the grounding resistance is stable. If the corrected resistance value D within time t-1 is2(t-1) The average resistance value PD after correction before time t-1 2(t-1) If the difference between the ground resistance and the measured ground resistance exceeds a preset threshold, it may indicate that the ground resistance is changing significantly and further inspection or maintenance measures are required;

[0118] "XC=c*(D 3(t-1) -D 2(t) ) 2 This term reflects the cyclic effect, which calculates the resistance evaluation value D at the previous moment t-1 3(t-1) The corrected resistance value D at the current time t 2(t) The square of the difference between them is multiplied by a loop feedback coefficient c. This difference term reflects the change of the resistance value at consecutive time points.

[0119] The dynamic stability assessment in this algorithm unit usually involves statistical analysis of the continuously measured grounding resistance data, including calculating the mean value and standard deviation to evaluate its stability and changing trend. If abnormal fluctuations are found or the preset threshold is exceeded, the system will trigger the loop feedback mechanism to automatically adjust the test frequency, increase monitoring points or send early warning signals to management personnel; through dynamic stability assessment, the changing trend of the resistance of the grounding device can be discovered in time, providing a basis for preventive maintenance and avoiding sudden failures; the loop feedback mechanism enables the test equipment to automatically adjust the test strategy according to real-time data, optimize resource allocation and improve test efficiency; the dynamic stability assessment is combined with the loop feedback to form a closed-loop control system that can continuously monitor and evaluate the status of the grounding device to ensure the long-term stable operation of the system.

[0120] See also Figures 1 to 4 , the feedback evaluation based on the detection changes of the comprehensive environmental temperature and humidity parameter correction unit and the dynamic stability evaluation and loop feedback unit is as follows:

[0121] S1, set the resistance value D after correction within time t 2(t) As the main evaluation value of the test, set the internal resistance evaluation value D at time t-1 3(t-1) The safety assessment value of the test is set to the dangerous resistance threshold D4 as the dangerous assessment value of the test;

[0122] S2, if the resistance value after correction within time t is D 2(t) Exceeding the resistance evaluation value D at time t-1 3(t-1) , and the dangerous resistance threshold D4 is not reached, the feedback enters the early warning interval. At this time, the system issues a warning to prompt the operator to pay attention to the status of the grounding system and to check and monitor it;

[0123] S3, if the resistance value after correction within time t is D 2(t)If the resistance exceeds the dangerous resistance threshold D4, it is considered that there is a serious problem with the grounding system or the environmental factors have changed dramatically. At this time, the system should immediately issue an emergency alarm and take emergency response measures;

[0124] S4, if the resistance value after correction within time t is D 2(t) The internal resistance evaluation value D at time t-1 3(t-1) If they are close to each other, it is considered to be a normal fluctuation;

[0125] The dynamic adjustment value XC plays a role of dynamic adjustment in the dynamic stability evaluation and loop feedback unit. When the difference term is large, the resistance value D after stable evaluation within time t is increased. 3(t) The resulting value reflects the instability of the resistance value.

[0126] In this embodiment, the algorithm unit compares the corrected resistance value D within time t 2(t) The internal resistance evaluation value D at time t-1 3(t-1) , can evaluate the stability of the resistance value. If the difference between the two is large, it means that the resistance value has changed significantly in a short period of time. This is caused by problems in the grounding system or sudden changes in environmental factors.

[0127] Among them, further responses to changes in environmental factors and grounding system problems are as follows: If it is confirmed that the change in resistance is caused by environmental factors, including sudden changes in temperature and humidity, and this change is within an acceptable range, then an observation strategy is adopted, waiting for the environment to return to stability before re-evaluating the status of the grounding system. If the environmental change exceeds the acceptable range, temporary measures need to be taken, including increasing the number of grounding devices or improving the grounding soil to deal with it; if it is confirmed that there is a problem with the grounding system itself, including corrosion of the grounding body and poor contact, it needs to be repaired or replaced immediately, including cleaning the grounding body, replacing damaged parts or re-laying the grounding grid.

[0128] In summary, in the specific implementation process, by continuously monitoring and evaluating the changes in resistance values, small fluctuations and potential problems in the grounding system can be discovered in a timely manner, thereby improving the sensitivity of detection; by introducing historical data and dynamic adjustment items, the stability of the grounding system can be evaluated more accurately, reducing false alarms and missed alarms, and enhancing system stability; when the system issues a warning or emergency alarm, the severity and urgency of the problem are judged based on the results and change range of the dynamic stability evaluation and loop feedback unit, thereby making corresponding maintenance decisions; through continuous monitoring and evaluation of the status of the grounding system, maintenance plans and resource allocation can be reasonably arranged to avoid unnecessary waste and delays.

[0129] For example 2, please refer to Figures 1 to 4The test accuracy of the ground resistance tester reaches 0.1 ohm. When the resistance of the gas station is less than 10 ohms, it is considered qualified. If it is unqualified, it will be reported immediately to the headquarters to send professionals to check the grounding system. The LED display screen can directly display the ground resistance value within a few seconds after each startup.

[0130] The shell of the ground resistance tester uses an explosion-proof type. When testing, the ground resistance tester fluctuates to the on position to connect the wires for testing. After the test, it fluctuates to the off position to cut off the wires and shut down.

[0131] In this embodiment, the ground resistance tester is equipped with a small LED display screen, which can directly display the ground resistance value within a few seconds after each startup, which improves the convenience and intuitiveness of the display. The control of the test accuracy of the ground resistance tester can also ensure the safety and accuracy of the ground resistance tester during testing. In addition, the shell uses an explosion-proof type of ground resistance tester, which can further ensure the safety of the ground resistance tester when used outdoors, and only enters the power-on state during testing, which not only achieves the purpose of energy saving and resource saving, but also ensures the safe tangent state when the test is turned off.

[0132] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An online automatic test method for the resistance of a gas station grounding device, characterized in that: The specific test steps of the online automatic resistance test method are as follows:

1. Test equipment installation and configuration preparation S1. Select a ground resistance tester that meets the requirements and has a test accuracy of 0.1 ohm. The ground resistance tester has a switch, uses the three-wire test principle, and is equipped with an LED display screen and disposable battery power supply; S2. Install the bull nose connector on the test line and auxiliary grounding wire of the tester, and fix it on the test point and auxiliary grounding electrode with screws; S3. Connect the RS485 networking device to the ground resistance tester; S4. Install a multi-channel resistance collector in the gas station and connect it to the RS485 networking device of the tester through the RS485 interface; S5. Connect the multi-channel resistance collector to the computer at the gas station through the RS485 interface and upload the data to the computer in real time; S6. Check that the computers at the gas station are connected to the Internet and the data can be aggregated to the company headquarters; 2. Test equipment to obtain calibration and evaluation feedback; Data acquisition, the resistance data collected in real time is transmitted to the multi-channel resistance collector through the measurement and detection module of the RS485 networking device; Data correction processing: Through the data processing module, the continuously collected resistance data is corrected to eliminate the influence of environmental factors, and then stability evaluation is performed to determine whether the feedback grounding device is in a stable state. The data processing module includes a real-time data measurement and acquisition unit, a comprehensive environmental temperature and humidity parameter correction unit, and a dynamic stability evaluation and loop feedback unit; Data upload: record the collected resistance data, the results of each test and the alarm information on the computer at the company headquarters and generate a detailed test report; The equipment used in the measurement and detection module includes a high-precision ground resistance tester and an environmental sensor, and the equipment used in the data processing module includes a data transmission device, a computer, and an embedded processing system; The calculation formula of the real-time data measurement and acquisition unit is as follows: D 1（t） =Y AB（t） / H AB ; in: D 1（t） is the foundation grounding resistance value at time t; Y AB（t） is the voltage difference between AB at time t, H AB Inject a constant current value between AB, A is the test voltage pole, B is the test current pole, and it is obtained through the RS485 networking device; The calculation formula of the comprehensive environmental temperature and humidity parameter correction unit is as follows: ； in: D 2（t） is the resistance value after correction at time t; WJZ is the temperature correction factor; a is the temperature coefficient; W （t） is the temperature value at time t; CW is the reference temperature value; SJZ is the humidity correction factor; b is the humidity influence coefficient; S （t） is the relative humidity value at time t; CS is the reference relative humidity value; The calculation formula of the dynamic stability evaluation and loop feedback unit is as follows: ； ； ； in: D 3（t） is the resistance value after stable evaluation at time t; γ is the weight coefficient; D 2（t-1） is the resistance value after correction at time t-1; PD 2（t-1） is the average value of the corrected resistance before time t-1, C is the total number of detections, k is the time window width, D 2i is the square value of the i-th grounding resistance; XC is the dynamic adjustment value; c is the loop feedback coefficient; D 3（t-1） is the resistance evaluation value at time t-1.

2. The method for online automatic testing of resistance of a gas station grounding device according to claim 1, characterized in that: The feedback evaluation based on the detection changes of the comprehensive environmental temperature and humidity parameter correction unit and the dynamic stability evaluation and loop feedback unit is as follows: S1, set the resistance value D after correction at time t 2（t） As the main evaluation value of the test, set the resistance evaluation value D at time t-1 3（t-1） The safety assessment value of the test is set to the dangerous resistance threshold D4 as the dangerous assessment value of the test; S2, if the resistance value after correction at time t is D 2（t） Exceeding the resistance evaluation value D at time t-1 3（t-1） , and the dangerous resistance threshold D4 is not reached, the feedback enters the early warning interval. At this time, the system issues a warning to prompt the operator to pay attention to the status of the grounding system and to check and monitor it; S3, if the resistance value after correction at time t is D 2（t） If the resistance exceeds the dangerous resistance threshold D4, it is considered that there is a serious problem with the grounding system or the environmental factors have changed dramatically. At this time, the system should immediately issue an emergency alarm and take emergency response measures; S4, if the resistance value after correction at time t is D 2（t） The resistance evaluation value D at time t-1 3（t-1） If they are close to each other, it is considered to be normal fluctuation.

3. The method for online automatic testing of resistance of a gas station grounding device according to claim 2, characterized in that: The dynamic adjustment value XC plays a role of dynamic adjustment in the dynamic stability evaluation and loop feedback unit. When the difference term is large, the resistance value D after the stable evaluation at time t is increased. 3（t） The resulting value reflects the instability of the resistance value.

4. The method for online automatic testing of resistance of a gas station grounding device according to claim 1, characterized in that: The test accuracy of the ground resistance tester reaches 0.1 ohm. When the resistance of the gas station is less than 10 ohms, it is considered qualified. If it is unqualified, it will be reported immediately to the headquarters to send professionals to check the grounding system. The LED display screen can directly display the ground resistance value within a few seconds after each startup.

5. The method for online automatic testing of resistance of a gas station grounding device according to claim 4, characterized in that: The shell of the ground resistance tester is of flameproof type. When testing, the ground resistance tester fluctuates to the on position to connect the wires for testing, and after the test, it fluctuates to the off position to cut off the wires and shut down.

Images