Method and device for detecting overheating fault of cable in switch cabinet

Abstract

The invention provides a method and device for detecting an overheating fault of a cable in a switch cabinet, and belongs to the technical field of cable detection. The method comprises the following steps: acquiring the detection voltage of a gas sensor when the switch cabinet runs and the initial resistance of the gas sensor when the switch cabinet does not run; calculating sensitivity characteristic parameters according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet does not operate; when the sensitivity characteristic parameters meet early warning conditions, cable overheating early warning information is generated; wherein the early warning condition comprises a sensitivity characteristic parameter threshold value, and the sensitivity characteristic parameter threshold value is set according to a preset temperature so as to determine a temperature range of cable overheating early warning. According to the invention, the cable overheating fault in the switch cabinet can be rapidly detected.

Description

Technical Field

[0001] The present invention relates to the technical field of cable detection, and in particular to a method and device for detecting overheating faults of cables inside a switch cabinet. Background Art

[0002] Switchgear is an important equipment in the power system. Cable failure inside switchgear may cause local power outages and disrupt social production processes. In extreme cases, overheating of cables inside switchgear may cause fires, posing a major threat to public safety and property. In the context of power equipment maintenance, temperature index is a key indicator for evaluating the operating status of switchgear cables and other equipment.

[0003] In practice, especially for 35kV and 10kV switchgear cables, the main reason for overheating is the heating of key components in the cabinet. The circuit breaker contacts and the joints between the busbar and the cable in the cabinet cable room are continuously subjected to high voltage, high current and strong magnetic field. When detecting the temperature of the cable, due to the large temperature decay of the cable, when the inside of the cable is very hot, the temperature around the cable may decay to normal. Therefore, directly using a temperature sensor cannot accurately detect the temperature of the cable.

[0004] In the prior art, such as the patent with application number 202410977718.X, when detecting cables, it is necessary to measure data such as the voltage, ambient temperature and humidity of the gas sensor, and then make a subsequent judgment on whether the cable is overheated. Many types of data need to be collected, which makes the judgment process cumbersome and reduces the efficiency of cable detection. Summary of the invention

[0005] The embodiment of the present invention provides a method and device for detecting overheating faults of cables inside a switch cabinet, so as to solve the problem of quickly detecting overheating faults of cables inside a switch cabinet.

[0006] In a first aspect, an embodiment of the present invention provides a method for detecting an overheating fault of a cable inside a switch cabinet, comprising:

[0007] Acquire the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation;

[0008] Calculating a sensitivity characteristic parameter according to a detection voltage of the gas sensor and an initial resistance of the gas sensor when the switch cabinet is not in operation;

[0009] When the sensitivity characteristic parameter meets the warning condition, cable overheating warning information is generated; wherein the warning condition includes a sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheating warning.

[0010] In a possible implementation, obtaining the detection voltage of the gas sensor when the switch cabinet is running includes:

[0011] Obtaining a power supply voltage and a load detection voltage when the switch cabinet is in operation;

[0012] The detection voltage of the gas sensor is calculated according to the power supply voltage and the load detection voltage when the switch cabinet is running.

[0013] In a possible implementation, obtaining the initial resistance of the gas sensor when the switch cabinet is not in operation includes:

[0014] Obtaining the power supply voltage and the initial load voltage and load resistance when the switch cabinet is not in operation;

[0015] Calculating the initial voltage of the gas sensor according to the power supply voltage and the initial voltage of the load when the switch cabinet is not in operation;

[0016] The initial resistance of the gas sensor is calculated based on the load resistance, the initial voltage of the gas sensor, and the load initial voltage.

[0017] In a possible implementation, calculating the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation includes:

[0018] Obtaining a load resistance and a load detection voltage when the switch cabinet is in operation;

[0019] Calculate the detection resistance of the gas sensor when the switch cabinet is in operation according to the detection voltage of the gas sensor when the switch cabinet is in operation, the load resistance and the load detection voltage when the switch cabinet is in operation;

[0020] The sensitivity characteristic parameter is calculated according to the initial resistance of the gas sensor when the switch cabinet is not in operation and the detection resistance of the gas sensor when the switch cabinet is in operation.

[0021] In a possible implementation, the sensitivity characteristic parameter threshold includes a plurality of sub-sensitivity characteristic parameter thresholds;

[0022] When the sensitivity characteristic parameter meets the warning condition, generating cable overheat warning information includes:

[0023] The sensitivity characteristic parameter is compared with each sub-sensitivity characteristic parameter threshold value to determine the operation status information of the cable; wherein each sub-sensitivity characteristic parameter threshold value corresponds to a different preset temperature.

[0024] In a possible implementation manner, the sensitivity characteristic parameter threshold includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

[0025] In a possible implementation, when the sensitivity characteristic parameter meets the warning condition, generating cable overheat warning information includes:

[0026] When the sensitivity characteristic parameter is less than or equal to the first sensitivity characteristic parameter threshold, determining that the current temperature of the cable is less than or equal to a first preset temperature, and generating normal operation information;

[0027] When the sensitivity characteristic parameter is greater than the first sensitivity characteristic parameter threshold and less than or equal to the second sensitivity characteristic parameter threshold, determining that the current temperature of the cable is between the first preset temperature and the second preset temperature, and generating warning information;

[0028] When the sensitivity characteristic parameter is greater than the second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is higher than the second preset temperature, and overheating information is generated; wherein, the first sensitivity characteristic parameter corresponds to the first preset temperature, the second sensitivity characteristic parameter corresponds to the second preset temperature, the first sensitivity characteristic parameter threshold is less than the second sensitivity characteristic parameter threshold, and the first preset temperature is less than the second preset temperature.

[0029] In a possible implementation, when the sensitivity characteristic parameter meets the warning condition, before generating the cable overheating warning information, the method further includes:

[0030] Acquire a preset temperature; wherein the preset temperature includes the first preset temperature and the second preset temperature;

[0031] Obtaining the power supply voltage and the load voltage and load resistance at the preset temperature;

[0032] Calculating the gas sensor voltage at a preset temperature according to the power supply voltage and the load voltage at the preset temperature;

[0033] The sensitivity characteristic parameter threshold corresponding to the preset temperature is calculated based on the gas sensor voltage, load voltage and load resistance at the preset temperature; wherein the sensitivity characteristic parameter threshold corresponding to the preset temperature includes the first sensitivity characteristic parameter threshold and the second sensitivity characteristic parameter threshold.

[0034] In a second aspect, an embodiment of the present invention provides a switch cabinet internal cable overheating fault detection device, comprising:

[0035] A detection voltage and initial resistance acquisition module, used to acquire the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation;

[0036] A sensitivity characteristic parameter calculation module, used to calculate the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation;

[0037] A cable overheat warning information generation module is used to generate cable overheat warning information when the sensitivity characteristic parameter meets the warning condition; wherein the warning condition includes a sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheat warning.

[0038] In a possible implementation, the detection voltage and initial resistance acquisition module is used to:

[0039] Obtain the detection voltage of the gas sensor when the switch cabinet is running, including:

[0040] Obtaining a power supply voltage and a load detection voltage when the switch cabinet is in operation;

[0041] The detection voltage of the gas sensor is calculated according to the power supply voltage and the load detection voltage when the switch cabinet is running.

[0042] The embodiment of the present invention provides a method and device for detecting overheating faults of cables inside a switch cabinet. The method obtains the detection voltage of a gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation, and calculates the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation. The initial resistance of the gas sensor when the switch cabinet is not in operation can be calculated before the cable is detected, and there is no need to repeat the calculation. When the cable is detected each time, it is only necessary to obtain the detection voltage of the gas sensor when the switch cabinet is in operation, and the sensitivity characteristic parameter can be calculated according to the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor calculated in advance. The only parameter that needs to be obtained during the calculation process is the detection voltage of the gas sensor, and the types of parameters involved are small, which reduces the calculation complexity and amount, and improves the detection efficiency of cable overheating faults. When the cable is detected, when the sensitivity characteristic parameter meets the warning condition, the cable overheating warning information is generated, and the warning condition includes the sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to the preset temperature. The current temperature range of the cable is determined according to the sensitivity characteristic parameter and the sensitivity parameter threshold to determine whether an overheating warning is required. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 is a schematic diagram of a system for detecting overheating faults of cables inside a switch cabinet provided by an embodiment of the present invention;

[0045] Figure 2 is a circuit diagram of a voltage measurement unit of a gas sensor provided by an embodiment of the present invention;

[0046] Figure 3 is a flow chart of an implementation method for detecting overheating faults of cables inside a switch cabinet provided by an embodiment of the present invention;

[0047] Figure 4 It is a flow chart of a method for generating cable overheat warning information provided by an embodiment of the present invention;

[0048] Figure 5 It is a flow chart of a method for testing sensitivity characteristic parameters of a gas sensor at different temperatures provided by an embodiment of the present invention;

[0049] Figure 6 is a schematic diagram of voltage results of a load resistor at different temperatures provided by an embodiment of the present invention;

[0050] Figure 7 It is a structural schematic diagram of a switch cabinet internal cable overheat fault detection device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0052] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0053] Figure 1 A schematic diagram of a system for detecting overheating faults of cables inside a switch cabinet provided by an embodiment of the present invention. Figure 1As shown, the system for detecting overheating faults of cables inside the switch cabinet includes a voltage measuring unit of a gas sensor, an OLED display, an audible and visual alarm unit, a central control unit, and a serial data transmission unit. When the temperature of the cable changes, the gas around the cable changes, causing the voltage of the gas sensor to change. The voltage of the gas sensor is measured by the voltage measuring unit of the gas sensor, and the measured voltage of the gas sensor is transmitted to the central control unit. The central control unit converts the voltage of the gas sensor into a sensitivity characteristic parameter. When the threshold of the sensitivity characteristic parameter is reached, the audible and visual alarm unit is controlled to sound an alarm. At the same time, the OLED display displays the obtained voltage of the gas sensor, and communicates with the outside through the serial data transmission unit. Among them, the audible and visual alarm unit includes a buzzer and an LED indicator.

[0054] like Figure 2 , is the circuit diagram of the voltage measurement unit of the gas sensor. The voltage measurement unit of the gas sensor includes a power supply, a gas sensor, a load resistor and a filter. When the temperature of the cable changes, the gas around the cable changes, causing the resistance of the gas sensor to change, which is converted into voltage through the load resistor. The load voltage is obtained through ADC high-speed acquisition, and the voltage of the gas sensor is calculated based on the difference between the power supply voltage and the load voltage. The filter in the circuit plays a role in filtering and removing noise.

[0055] Figure 3 The implementation flow chart of the method for detecting overheating faults of cables inside a switch cabinet provided by an embodiment of the present invention is described in detail as follows:

[0056] Step 301 , obtaining the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation.

[0057] The initial resistance of the gas sensor when the switch cabinet is not in operation represents a reference state of the resistance of the gas sensor, and serves as a benchmark to facilitate the calculation of subsequent sensitivity characteristic parameters.

[0058] The detection voltage of the gas sensor is obtained by the difference between the power supply voltage and the voltage of the load resistor, and the power supply voltage is fixed, that is, each time only the voltage of the load resistor is needed to calculate the detection voltage of the gas sensor. During detection, the detection resistance of the gas sensor is calculated based on the obtained detection voltage of the gas sensor, and then the initial resistance of the gas sensor is ratioed with the detection resistance of the gas sensor to obtain the sensitivity characteristic parameter.

[0059] When performing cable overheat fault detection, it is only necessary to obtain the detection voltage of the gas sensor each time to calculate the sensitivity characteristic parameters. During detection, fewer types of parameters need to be obtained, which reduces the amount of calculation and complexity of calculation, thereby improving the calculation efficiency of the sensitivity characteristic parameters and thus improving the efficiency of overheat fault detection.

[0060] In a possible implementation, obtaining the initial resistance of the gas sensor when the switch cabinet is not in operation includes:

[0061] Obtain the power supply voltage and the initial load voltage and load resistance when the switch cabinet is not in operation;

[0062] Calculate the initial voltage of the gas sensor based on the power supply voltage and the initial voltage of the load when the switch cabinet is not running;

[0063] The initial resistance of the gas sensor is calculated based on the load resistance, the initial voltage of the gas sensor, and the load initial voltage.

[0064] Step 302: Calculate the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation.

[0065] When the switch cabinet is not in operation, the initial resistance of the gas sensor is a fixed value. Before detecting a cable overheating fault, it only needs to be calculated and recorded. The initial resistance will not change. When calculating the sensitivity characteristic parameters, the initial resistance can be directly obtained. It is not necessary to calculate each time the cable is detected. Therefore, it can save the sensitivity characteristic parameter calculation time, thereby saving the cable fault detection time and improving the fault detection efficiency.

[0066] During detection, the detection resistance of the gas sensor can be calculated based on the detection voltage of the gas sensor, and the sensitivity characteristic parameter can be calculated based on the ratio of the initial resistance of the gas sensor and the detection resistance of the gas sensor.

[0067] Step 303, when the sensitivity characteristic parameter meets the warning condition, generate cable overheat warning information; wherein the warning condition includes a sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheat warning.

[0068] The warning condition is a condition set in advance. When the sensitivity characteristic parameter meets the warning condition, the system will trigger the warning signal. The sensitivity characteristic parameter threshold in the warning condition defines the level at which the sensitivity characteristic parameter output by the gas sensor reaches the system will consider that the cable may be overheated. For example, when the sensitivity characteristic parameter is greater than the sensitivity parameter threshold, the system will consider that the cable temperature is too high and a warning is required.

[0069] The preset temperature is the temperature value preset by the user according to the needs or safety standards. When the actual temperature of the cable exceeds this preset value, the system will consider the cable to be in an overheated state. The sensitivity characteristic parameter threshold is set at the corresponding preset temperature, that is, the sensitivity characteristic parameter threshold corresponds to the preset temperature one by one. When the sensitivity characteristic parameter threshold is determined, the corresponding preset temperature can also be determined. The sensitivity characteristic parameter threshold divides the sensitivity characteristic parameter into a range, and correspondingly divides the temperature into a range.

[0070] When judging whether the cable is overheated, after calculating the sensitivity characteristic parameter, the sensitivity characteristic parameter is compared with the sensitivity characteristic parameter threshold to determine the range of the sensitivity characteristic parameter (at the same time, the range of the current temperature of the cable corresponding to the sensitivity characteristic parameter is also determined), and then determine whether an early warning is needed and the level of the early warning.

[0071] Cable overheating fault detection helps to improve the safety and reliability of the power system and reduce faults and accidents caused by cable overheating.

[0072] The embodiment of the present invention obtains the detection voltage of the gas sensor when the switch cabinet is running and the initial resistance of the gas sensor when the switch cabinet is not running, and calculates the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not running. The initial resistance of the gas sensor when the switch cabinet is not running can be calculated before the cable detection, and there is no need to repeat the calculation. When the cable is detected each time, it is only necessary to obtain the detection voltage of the gas sensor when the switch cabinet is running, and the sensitivity characteristic parameter can be calculated according to the detection voltage of the gas sensor when the switch cabinet is running and the initial resistance of the gas sensor that has been calculated in advance. The parameter that needs to be obtained during the calculation process is only the detection voltage of the gas sensor, and the types of parameters involved are small, which reduces the calculation complexity and amount, and improves the detection efficiency of the cable overheating fault. When the cable is detected, when the sensitivity characteristic parameter meets the warning condition, the cable overheating warning information is generated, and the warning condition includes the sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to the preset temperature. The current temperature range of the cable is determined according to the sensitivity characteristic parameter and the sensitivity parameter threshold to determine whether an overheating warning is required.

[0073] In a possible implementation, obtaining a detection voltage of a gas sensor when the switch cabinet is running includes:

[0074] Obtain the power supply voltage and the load detection voltage when the switch cabinet is running;

[0075] The detection voltage of the gas sensor is calculated based on the power supply voltage and the load detection voltage when the switch cabinet is in operation.

[0076] like Figure 2The power supply voltage is the sum of the detection voltage of the gas sensor and the load detection voltage. When the switch cabinet is running, the temperature of the cable changes, causing the gas around the cable to change. The gas sensor senses the change in gas, thereby changing the resistance of the gas sensor, causing the detection voltage of the gas sensor to change. Since the power supply voltage remains unchanged, the load detection voltage will change. Therefore, as long as the load detection voltage is measured and the power supply voltage is subtracted from the load detection voltage, the detection voltage of the gas sensor can be obtained. Compared with directly measuring the detection voltage of the gas sensor, the accuracy, reliability and economy of the measurement can be improved, while simplifying system design and maintenance.

[0077] In a possible implementation, the calculation formula of the initial resistance of the gas sensor when the switch cabinet is not in operation is as follows:

[0078] R0=R L V0 / V RL0

[0079] Where R0 is the initial resistance of the gas sensor when the switch cabinet is not in operation, R L is the load resistance, V0 is the initial voltage of the gas sensor, V RL0 Initial voltage of the load when the switchgear is not in operation.

[0080] In this embodiment, the load resistor R L It is known that the initial voltage V0 of the gas sensor depends on the initial voltage V RL0 Subtract the power supply voltage to get the initial load voltage V RL0 It can be measured, the power supply voltage can be measured, and its value remains unchanged. After calculating the initial resistance of the gas sensor according to the formula, the initial resistance will not change, so just record it for backup.

[0081] In a possible implementation, the sensitivity characteristic parameter is calculated according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation, including:

[0082] Obtain the load resistance and the load detection voltage when the switch cabinet is running;

[0083] Calculate the detection resistance of the gas sensor when the switch cabinet is in operation according to the detection voltage of the gas sensor when the switch cabinet is in operation, the load resistance and the load detection voltage when the switch cabinet is in operation;

[0084] The sensitivity characteristic parameter is calculated based on the initial resistance of the gas sensor when the switch cabinet is not in operation and the detection resistance of the gas sensor when the switch cabinet is in operation.

[0085] Optionally, the calculation formula of the detection resistance of the gas sensor when the switch cabinet is running is as follows:

[0086] RS =R L ·V / V RL

[0087] In the formula, R S is the detection resistance of the gas sensor when the switch cabinet is running, R L is the load resistance, V is the detection voltage of the gas sensor when the switch cabinet is running, V RL It is the load detection voltage when the switch cabinet is running.

[0088] The calculation formula of the sensitivity characteristic parameter is as follows:

[0089] S=R0 / R S

[0090] Where S is the sensitivity characteristic parameter, R0 is the initial resistance of the gas sensor when the switch cabinet is not in operation, and R S It is the detection resistance of the gas sensor when the switch cabinet is running.

[0091] In this embodiment, the load resistor R L It is a fixed value and will not change. You can directly obtain it. The load detection voltage V RL It can be measured that the detection voltage V of the gas sensor is composed of the power supply voltage and the load detection voltage V RL Since the power supply voltage is fixed, the detection voltage of the gas sensor can be obtained by measuring the load detection voltage, and then the detection resistance R of the gas sensor can be calculated. S , and then calculate the sensitivity characteristic parameters, while the initial resistance R0 of the gas sensor has been calculated according to the previous steps and is a fixed value, which can be used directly. That is, in each cable overheat fault detection, only the load detection voltage parameter needs to be measured to calculate the sensitivity characteristic parameters, so as to detect the cable overheat fault. The number of parameters to be obtained is small, the calculation is simple, and the efficiency of cable overheat detection is improved.

[0092] In a possible implementation, the sensitivity characteristic parameter threshold includes a plurality of sub-sensitivity characteristic parameter thresholds;

[0093] When the sensitivity characteristic parameters meet the warning conditions, the cable overheating warning information generated includes:

[0094] The sensitivity characteristic parameter is compared with each sub-sensitivity characteristic parameter threshold value to determine the operation status information of the cable; wherein each sub-sensitivity characteristic parameter threshold value corresponds to a different preset temperature.

[0095] In this embodiment, multiple sensitivity characteristic parameter thresholds can be set to divide the temperature into multiple intervals. Since each sub-sensitivity characteristic parameter threshold corresponds to a different preset temperature, it can help evaluate the performance and safety status of the cable at different temperatures, conduct a detailed analysis of the performance of the cable, and understand its operation under different temperature conditions. According to the comparison results, preventive maintenance or emergency repairs can be planned to avoid cable failures. By monitoring the operating status of the cable, the safe operation of the power system can be ensured to prevent power outages or fires caused by cable problems.

[0096] In another possible implementation, the sensitivity characteristic parameter threshold includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

[0097] In a possible implementation, when the sensitivity characteristic parameter meets the warning condition, generating cable overheat warning information includes:

[0098] When the sensitivity characteristic parameter is less than or equal to the first sensitivity characteristic parameter threshold, determining that the current temperature of the cable is less than or equal to the first preset temperature, and generating normal operation information;

[0099] When the sensitivity characteristic parameter is greater than a first sensitivity characteristic parameter threshold and less than or equal to a second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is between the first preset temperature and the second preset temperature, and an early warning message is generated;

[0100] When the sensitivity characteristic parameter is greater than the second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is higher than the second preset temperature, and overheating information is generated; wherein, the first sensitivity characteristic parameter corresponds to the first preset temperature, the second sensitivity characteristic parameter corresponds to the second preset temperature, the first sensitivity characteristic parameter threshold is less than the second sensitivity characteristic parameter threshold, and the first preset temperature is less than the second preset temperature. Figure 4 It is a flow chart of a method for generating cable overheat warning information.

[0101] In this embodiment, by dividing the first sensitivity characteristic parameter threshold and the second sensitivity characteristic parameter threshold, the operation status of the cable can be judged according to the sensitivity characteristic parameter of the cable, and corresponding early warning information can be generated to ensure the safe and stable operation of the power system. The temperature change of the cable can be dynamically monitored, and the operation status of the cable can be updated according to real-time data.

[0102] In a possible implementation, when the sensitivity characteristic parameter meets the warning condition, before generating the cable overheating warning information, the method further includes:

[0103] Obtaining a preset temperature; wherein the preset temperature includes a first preset temperature and a second preset temperature;

[0104] Obtain the power supply voltage and the load voltage and load resistance at the preset temperature;

[0105] Calculate the gas sensor voltage at a preset temperature according to the power supply voltage and the load voltage at the preset temperature;

[0106] The sensitivity characteristic parameter threshold corresponding to the preset temperature is calculated based on the gas sensor voltage, load voltage and load resistance at the preset temperature; wherein the sensitivity characteristic parameter threshold corresponding to the preset temperature includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

[0107] In this embodiment, in different regions and under different usage requirements, the safety temperature of the switch cabinet that needs to be set is different. Under different safety temperature conditions, the measured voltage of the gas sensor is different, and the corresponding sensitivity characteristic parameter threshold is obtained according to the voltage of the gas sensor.

[0108] The sensitivity characteristic parameter test method of gas sensor at different temperatures is as follows: Figure 5 As shown, first preheat the sensor for one hour, then conduct the experiment, set the preset temperature, heat the cable at the preset temperature for 15 minutes, and then make the cable maintain the preset temperature. Measure the voltage of the gas sensor at the preset temperature, convert the voltage of the gas sensor into the sensitivity characteristic parameter, adjust different preset temperatures, and get the sensitivity characteristic parameters at different temperatures. When the preset temperature is greater than 300℃, the sensitivity characteristic parameter test is no longer performed.

[0109] like Figure 6 is the load resistance R at different temperatures L Voltage diagram, when the preset temperature is higher, the load resistance R L The voltage V RL increases. Since the power supply voltage remains unchanged, the voltage V of the gas sensor decreases, and the load resistance R L The detection resistance R of the gas sensor will not change when the switch cabinet is running. S When the switch cabinet is not running, the initial resistance R0 of the gas sensor remains unchanged, and the sensitivity characteristic parameter S increases. When the first preset temperature corresponding to the first sensitivity characteristic parameter threshold is lower than the second preset temperature corresponding to the second sensitivity characteristic parameter threshold, the first sensitivity characteristic parameter threshold is lower than the second sensitivity characteristic parameter threshold.

[0110] Exemplarily, the temperatures corresponding to the first sensitivity characteristic parameter threshold value A1 and the second sensitivity characteristic parameter threshold value A2 are shown in Table 1, A1 corresponds to 100° C., and A2 corresponds to 220° C., and at this time A1 is smaller than A2.

[0111] Table 1 Sensitivity characteristic parameter thresholds A1 and A2 corresponding to temperature

[0112]

[0113] The different temperatures, different working conditions and warning methods corresponding to different sensitivity characteristic parameters are shown in Table 2. It can be seen from the table that when the sensitivity characteristic parameter is less than or equal to A1, the temperature of the corresponding cable is less than or equal to 100°C, the cable operates normally, there is no sound prompt, and the indicator light is always green. When the sensitivity characteristic parameter is greater than A1 and less than or equal to A2, the temperature of the corresponding cable is greater than 100°C and less than or equal to 220°C, the cable is in a warning condition, there is no sound prompt, and the indicator light flashes red. When the sensitivity characteristic parameter is greater than A2, the temperature of the corresponding cable is greater than 220°C, the cable is in an overheating condition, a long sound prompt is given, and the indicator light is always red.

[0114] Table 2 Different temperatures, different working conditions and warning methods corresponding to different sensitivity characteristic parameters

[0115]

[0116] The present application uses a gas sensor to sense the gas signal generated by the decomposition of the cable material, performs real-time detection and issues an alarm when the alarm condition is reached; obtains the temperature range for normal operation of the cable by analyzing the sensitivity characteristic parameters of the gas sensor; and provides an early warning effect for cable fires.

[0117] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0118] The following is an embodiment of the device of the present invention. For details not described in detail therein, reference may be made to the corresponding method embodiment described above.

[0119] Figure 7 The structure diagram of the cable overheat fault detection device inside the switch cabinet provided by the embodiment of the present invention is shown. For the convenience of description, only the part related to the embodiment of the present invention is shown, which is described in detail as follows:

[0120] like Figure 7 As shown, the switch cabinet internal cable overheating fault detection device 7 includes:

[0121] A detection voltage and initial resistance acquisition module 71 is used to acquire the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation;

[0122] A sensitivity characteristic parameter calculation module 72, used to calculate the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation;

[0123] The cable overheat warning information generation module 73 is used to generate cable overheat warning information when the sensitivity characteristic parameter meets the warning condition; wherein the warning condition includes the sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheat warning.

[0124] In a possible implementation, the detection voltage and initial resistance acquisition module 71 is used to:

[0125] Obtain the detection voltage of the gas sensor when the switch cabinet is running, including:

[0126] Obtain the power supply voltage and the load detection voltage when the switch cabinet is running;

[0127] The detection voltage of the gas sensor is calculated based on the power supply voltage and the load detection voltage when the switch cabinet is in operation.

[0128] In a possible implementation, the detection voltage and initial resistance acquisition module 71 is used to:

[0129] Obtain the initial resistance of the gas sensor when the switch cabinet is not in operation, including:

[0130] Obtain the power supply voltage and the initial load voltage and load resistance when the switch cabinet is not in operation;

[0131] Calculate the initial voltage of the gas sensor based on the power supply voltage and the initial voltage of the load when the switch cabinet is not running;

[0132] The initial resistance of the gas sensor is calculated based on the load resistance, the initial voltage of the gas sensor, and the load initial voltage.

[0133] In a possible implementation, the sensitivity characteristic parameter calculation module 72 is used to:

[0134] The sensitivity characteristic parameters are calculated based on the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation, including:

[0135] Obtain the load resistance and the load detection voltage when the switch cabinet is running;

[0136] Calculate the detection resistance of the gas sensor when the switch cabinet is in operation according to the detection voltage of the gas sensor when the switch cabinet is in operation, the load resistance and the load detection voltage when the switch cabinet is in operation;

[0137] The sensitivity characteristic parameter is calculated based on the initial resistance of the gas sensor when the switch cabinet is not in operation and the detection resistance of the gas sensor when the switch cabinet is in operation.

[0138] In a possible implementation, the cable overheating warning information generating module 73 is used to:

[0139] The sensitivity characteristic parameter threshold includes a plurality of sub-sensitivity characteristic parameter thresholds;

[0140] When the sensitivity characteristic parameters meet the warning conditions, the cable overheating warning information generated includes:

[0141] The sensitivity characteristic parameter is compared with each sub-sensitivity characteristic parameter threshold in sequence to determine the operating status information of the cable; wherein each sub-sensitivity characteristic parameter threshold corresponds to a different preset temperature, and each sub-sensitivity characteristic parameter threshold is sorted from low to high according to the preset temperature.

[0142] In a possible implementation, the cable overheating warning information generating module 73 is used to:

[0143] The sensitivity characteristic parameter threshold includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

[0144] In a possible implementation, the cable overheating warning information generating module 73 is used to:

[0145] When the sensitivity characteristic parameters meet the warning conditions, the cable overheating warning information generated includes:

[0146] When the sensitivity characteristic parameter is less than or equal to the first sensitivity characteristic parameter threshold, determining that the current temperature of the cable is less than or equal to the first preset temperature, and generating normal operation information;

[0147] When the sensitivity characteristic parameter is greater than a first sensitivity characteristic parameter threshold and less than or equal to a second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is between the first preset temperature and the second preset temperature, and an early warning message is generated;

[0148] When the sensitivity characteristic parameter is greater than the second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is higher than the second preset temperature, and overheating information is generated; wherein, the first sensitivity characteristic parameter corresponds to the first preset temperature, the second sensitivity characteristic parameter corresponds to the second preset temperature, the first sensitivity characteristic parameter threshold is less than the second sensitivity characteristic parameter threshold, and the first preset temperature is less than the second preset temperature.

[0149] In a possible implementation, the cable overheating warning information generating module 73 is used to:

[0150] When the sensitivity characteristic parameter meets the warning condition, before generating the cable overheat warning information, it also includes:

[0151] Obtaining a preset temperature; wherein the preset temperature includes a first preset temperature and a second preset temperature;

[0152] Obtain the power supply voltage and the load voltage and load resistance at the preset temperature;

[0153] Calculate the gas sensor voltage at a preset temperature according to the power supply voltage and the load voltage at the preset temperature;

[0154] The sensitivity characteristic parameter threshold corresponding to the preset temperature is calculated based on the gas sensor voltage, load voltage and load resistance at the preset temperature; wherein the sensitivity characteristic parameter threshold corresponding to the preset temperature includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

[0155] The embodiment of the present invention obtains the detection voltage of the gas sensor when the switch cabinet is running and the initial resistance of the gas sensor when the switch cabinet is not running, and calculates the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not running. The initial resistance of the gas sensor when the switch cabinet is not running can be calculated before the cable detection, and there is no need to repeat the calculation. When the cable is detected each time, it is only necessary to obtain the detection voltage of the gas sensor when the switch cabinet is running, and the sensitivity characteristic parameter can be calculated according to the detection voltage of the gas sensor when the switch cabinet is running and the initial resistance of the gas sensor that has been calculated in advance. The parameter that needs to be obtained during the calculation process is only the detection voltage of the gas sensor, and the types of parameters involved are small, which reduces the calculation complexity and amount, and improves the detection efficiency of the cable overheating fault. When the cable is detected, when the sensitivity characteristic parameter meets the warning condition, the cable overheating warning information is generated, and the warning condition includes the sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to the preset temperature. The current temperature range of the cable is determined according to the sensitivity characteristic parameter and the sensitivity parameter threshold to determine whether an overheating warning is required.

[0156] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0157] Those of ordinary skill in the art will appreciate that the templates, units, and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0158] If the module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned embodiments of the cable overheating fault detection method inside the switch cabinet can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium.

[0159] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for detecting overheating faults of cables inside a switch cabinet, characterized in that: include: Acquire the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation; Calculating a sensitivity characteristic parameter according to a detection voltage of the gas sensor and an initial resistance of the gas sensor when the switch cabinet is not in operation; When the sensitivity characteristic parameter meets the warning condition, cable overheating warning information is generated; wherein the warning condition includes a sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheating warning.

2. The method for detecting overheating faults of cables inside a switch cabinet according to claim 1, characterized in that: The step of obtaining the detection voltage of the gas sensor when the switch cabinet is running includes: Obtaining a power supply voltage and a load detection voltage when the switch cabinet is in operation; The detection voltage of the gas sensor is calculated according to the power supply voltage and the load detection voltage when the switch cabinet is running.

3. The method for detecting overheating faults of cables inside a switch cabinet according to claim 1, characterized in that: Obtaining the initial resistance of the gas sensor when the switch cabinet is not in operation includes: Obtaining the power supply voltage and the initial load voltage and load resistance when the switch cabinet is not in operation; Calculating the initial voltage of the gas sensor according to the power supply voltage and the initial voltage of the load when the switch cabinet is not in operation; The initial resistance of the gas sensor is calculated based on the load resistance, the initial voltage of the gas sensor, and the load initial voltage.

4. The method for detecting overheating faults of cables inside a switch cabinet according to claim 1, characterized in that: The calculating of the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation includes: Obtaining a load resistance and a load detection voltage when the switch cabinet is in operation; Calculate the detection resistance of the gas sensor when the switch cabinet is in operation according to the detection voltage of the gas sensor when the switch cabinet is in operation, the load resistance and the load detection voltage when the switch cabinet is in operation; The sensitivity characteristic parameter is calculated according to the initial resistance of the gas sensor when the switch cabinet is not in operation and the detection resistance of the gas sensor when the switch cabinet is in operation.

5. The method for detecting overheating faults of cables inside a switch cabinet according to claim 1, characterized in that: The sensitivity characteristic parameter threshold includes a plurality of sub-sensitivity characteristic parameter thresholds; When the sensitivity characteristic parameter meets the warning condition, generating cable overheat warning information includes: The sensitivity characteristic parameter is compared with each sub-sensitivity characteristic parameter threshold value to determine the operation status information of the cable; wherein each sub-sensitivity characteristic parameter threshold value corresponds to a different preset temperature.

6. The method for detecting overheating faults of cables inside a switch cabinet according to claim 1, characterized in that: The sensitivity characteristic parameter threshold includes a first sensitivity characteristic parameter threshold and a second sensitivity characteristic parameter threshold.

7. The method for detecting overheating faults of cables inside a switch cabinet according to claim 6, characterized in that: When the sensitivity characteristic parameter meets the warning condition, generating cable overheat warning information includes: When the sensitivity characteristic parameter is less than or equal to the first sensitivity characteristic parameter threshold, determining that the current temperature of the cable is less than or equal to a first preset temperature, and generating normal operation information; When the sensitivity characteristic parameter is greater than the first sensitivity characteristic parameter threshold and less than or equal to the second sensitivity characteristic parameter threshold, determining that the current temperature of the cable is between the first preset temperature and the second preset temperature, and generating warning information; When the sensitivity characteristic parameter is greater than the second sensitivity characteristic parameter threshold, it is determined that the current temperature of the cable is higher than the second preset temperature, and overheating information is generated; wherein, the first sensitivity characteristic parameter corresponds to the first preset temperature, the second sensitivity characteristic parameter corresponds to the second preset temperature, the first sensitivity characteristic parameter threshold is less than the second sensitivity characteristic parameter threshold, and the first preset temperature is less than the second preset temperature.

8. The method for detecting overheating faults of cables inside a switch cabinet according to claim 7, characterized in that: When the sensitivity characteristic parameter meets the warning condition, before generating the cable overheating warning information, the method further includes: Acquire a preset temperature; wherein the preset temperature includes the first preset temperature and the second preset temperature; Obtaining the power supply voltage and the load voltage and load resistance at the preset temperature; Calculating the gas sensor voltage at a preset temperature according to the power supply voltage and the load voltage at the preset temperature; The sensitivity characteristic parameter threshold corresponding to the preset temperature is calculated based on the gas sensor voltage, load voltage and load resistance at the preset temperature; wherein the sensitivity characteristic parameter threshold corresponding to the preset temperature includes the first sensitivity characteristic parameter threshold and the second sensitivity characteristic parameter threshold.

9. A switch cabinet internal cable overheating fault detection device, characterized in that: include: A detection voltage and initial resistance acquisition module, used to acquire the detection voltage of the gas sensor when the switch cabinet is in operation and the initial resistance of the gas sensor when the switch cabinet is not in operation; A sensitivity characteristic parameter calculation module, used to calculate the sensitivity characteristic parameter according to the detection voltage of the gas sensor and the initial resistance of the gas sensor when the switch cabinet is not in operation; A cable overheat warning information generation module is used to generate cable overheat warning information when the sensitivity characteristic parameter meets the warning condition; wherein the warning condition includes a sensitivity characteristic parameter threshold, and the sensitivity characteristic parameter threshold is set according to a preset temperature to determine the temperature range of the cable overheat warning.

10. The switch cabinet internal cable overheat fault detection device according to claim 9, characterized in that: The detection voltage and initial resistance acquisition module is used to: Obtain the detection voltage of the gas sensor when the switch cabinet is running, including: Obtaining a power supply voltage and a load detection voltage when the switch cabinet is in operation; The detection voltage of the gas sensor is calculated according to the power supply voltage and the load detection voltage when the switch cabinet is running.

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