Power supply line power outage detection method and system

Abstract

The present invention discloses a method and system for detecting power failure of a power supply line, which belongs to the technical field of power failure detection of power supply lines. The method includes obtaining the bus current, resistance current and capacitance current of a monitoring device connected in parallel with a lightning arrester monitor on a power supply line; taking the bus current of the monitoring device flowing to the ground direction as positive, if the bus current is 0, the resistance current is positive, the capacitance current is negative, and the bus current is the sum of the resistance current and the capacitance current, it indicates that the power failure discrimination condition is met, and the power supply line is in a power failure; the resistance current refers to the current flowing through the monitoring resistor in the monitoring device, and the capacitance current refers to the current flowing through the monitoring capacitor in the monitoring device; the monitoring resistor is connected in parallel with the monitoring capacitor. The present invention can accurately determine whether the power supply line is in a power failure without changing the original line, avoiding technical compatibility problems, safety problems and power supply interruption problems caused by the modification of the original line; and it is more convenient to install, and the installation time is greatly shortened.

Description

Technical Field

[0001] The invention relates to a method and a system for detecting power failure of a power supply line, belonging to the technical field of power failure detection of a power supply line. Background Art

[0002] In modern power systems, the stability and reliability of power supply lines are key to ensuring the normal distribution and use of electricity. However, power supply lines often face power outages and power shortages, which not only affect users' daily lives and production work, but may also lead to significant economic losses and safety hazards. In order to timely monitor and diagnose the status of power supply lines, some monitoring technologies and equipment have been widely used, such as sensor-based real-time monitoring systems, smart meters, and drone inspection technologies. These technologies can improve the monitoring capabilities of power supply lines to a certain extent and detect potential faults in advance.

[0003] However, existing monitoring technologies and equipment often require the removal and modification of existing lines during actual installation, which brings many disadvantages. First, the removal of the original lines will not only cause power outages and affect the normal power consumption of users, but may also increase construction costs and time, leading to project delays. Secondly, the modification of the original lines may cause technical compatibility issues and may even have a negative impact on the overall safety of the power supply system; in addition, some high-voltage lines do not allow the removal and modification of the original equipment. Summary of the invention

[0004] The object of the present invention is to provide a method and system for detecting power outages in power supply lines, so as to solve the technical compatibility problems, safety problems and power supply interruption problems existing in the prior art.

[0005] To achieve the above objectives, the present invention is implemented by adopting the following technical solutions:

[0006] In a first aspect, the present invention provides a method for detecting power outage in a power supply line, comprising:

[0007] Obtain the bus current, resistance current and capacitance current of the monitoring device connected in parallel with the arrester monitor on the power supply line;

[0008] The direction in which the bus current of the monitoring device flows to the ground is positive. If the bus current is 0, the resistor current is positive, the capacitor current is negative, and the bus current is the sum of the resistor current and the capacitor current, it indicates that the power outage judgment condition is met and the power supply line is in a power outage.

[0009] The resistor current refers to the current flowing through the monitoring resistor in the monitoring device, and the capacitor current refers to the current flowing through the monitoring capacitor in the monitoring device; the monitoring resistor is connected in parallel with the monitoring capacitor.

[0010] Furthermore, it also includes:

[0011] If the bus current, the resistor current and the capacitor current are all positive, and the bus current is the sum of the resistor current and the capacitor current, it indicates that the power outage judgment condition is met and the power supply line is not out of power.

[0012] Furthermore, it also includes:

[0013] If the bus current, the resistor current and the capacitor current do not satisfy the power outage determination condition and the non-power outage determination condition at the same time, it indicates that a fault occurs inside the monitoring device, and a monitoring device fault notification is issued to a preset receiving unit.

[0014] Furthermore, the impedance change rate of the arrester monitor is less than 0.1% after being connected in parallel with the monitoring device.

[0015] Furthermore, the internal resistance of the monitoring device is 200 to 9000 times the internal resistance of the arrester monitor.

[0016] In a second aspect, the present invention provides a power supply line power failure detection system, including a monitoring device, a data sampling module and a data processing module, wherein the monitoring device is connected in parallel with a lightning arrester monitor on the power supply line;

[0017] The monitoring device comprises a monitoring resistor and a monitoring capacitor, and the monitoring resistor and the monitoring capacitor are connected in parallel;

[0018] The data sampling module is used to collect the bus current, the resistor current and the capacitor current of the monitoring device, wherein the resistor current refers to the current flowing through the monitoring resistor, and the capacitor current refers to the current flowing through the monitoring capacitor;

[0019] The data processing module is used to execute any method described in the first aspect.

[0020] Furthermore, the resistance of the monitoring resistor is 200-300 megohms.

[0021] Further, the data acquisition module includes a bus current acquisition circuit;

[0022] The bus current acquisition circuit includes a current amplifier U2, a capacitor C1, an operational amplifier U3, a capacitor C2, a capacitor C3, a resistor R3 and a single-chip microcomputer U1;

[0023] The non-inverting input terminal VP and the inverting input terminal VN of the current amplifier U2 are respectively connected to the bus bars at both ends of the monitoring device;

[0024] The VCC power supply terminal of the current amplifier U2 is electrically connected to the positive power supply VCC-F, and is connected in series with the capacitor C1 and then grounded; the signal output terminal of the current amplifier U2 is connected in series with the capacitor C2 and then electrically connected to the inverting input terminal of the operational amplifier U3;

[0025] The inverting input terminal of the operational amplifier U3 is connected in series with a resistor R3 and then electrically connected to the output terminal of the operational amplifier U3; a diode D1 and a diode D2 are connected in reverse parallel between the non-inverting input terminal and the inverting input terminal of the operational amplifier U3; the output terminal of the operational amplifier U3 is connected in series with a capacitor C3 and then grounded, and the output terminal of the operational amplifier U3 is also connected to the ADC sampling pin of the single-chip computer U1;

[0026] The common terminal of the current amplifier U2, the non-inverting input terminal of the operational amplifier U3, and the power supply terminal are respectively connected to a voltage source.

[0027] Furthermore, the bus current sampling circuit also includes a transient suppression diode TVS1, and the signal output end of the current amplifier U2 and the in-phase input end of the operational amplifier U3 are respectively connected in series with the transient suppression diode TVS1 and then grounded.

[0028] Furthermore, the data acquisition module also includes a resistor current acquisition circuit, the circuit structure of the resistor current acquisition circuit is the same as the circuit structure of the bus current acquisition circuit, and when collecting the resistor current, the non-inverting input terminal VP and the inverting input terminal VN of the current amplifier U2 in the resistor current acquisition circuit are respectively connected to the two ends of the monitoring resistor;

[0029] Alternatively, the data acquisition module also includes a capacitor current acquisition circuit, the circuit structure of the capacitor current acquisition circuit is the same as the circuit structure of the bus current acquisition circuit, and when collecting the capacitor current, the non-phase input terminal VP and the inverting input terminal VN of the current amplifier U2 in the capacitor current acquisition circuit are respectively connected to the two ends of the monitoring capacitor.

[0030] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0031] The present invention provides a power outage detection method and system for a power supply line. It is unnecessary to change the original device of the power supply line. A monitoring device is connected in parallel to the original lightning arrester monitor to accurately judge whether the power supply line has a power outage by monitoring the change of current. During the installation of the equipment, it is unnecessary to change the original circuit structure of the lightning arrester grounding loop and the power supply line, thereby realizing automatic and rapid identification of power outages in the power supply line, avoiding technical compatibility problems, safety problems and power supply interruption problems caused by the modification of the original line; and it is more convenient to install and the installation time is greatly shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a flow chart of a power supply line power outage detection method corresponding to Embodiment 1 of the present invention;

[0033] Figure 2is a flow chart of a power supply line power outage detection method corresponding to Embodiment 2 of the present invention;

[0034] Figure 3 It is a schematic diagram of the installation position of the monitoring device provided by the present invention;

[0035] Figure 4 It is a schematic diagram of the structure of the monitoring device provided by the present invention;

[0036] Figure 5 is a schematic diagram of a current amplifier U2 in a data acquisition module provided by the present invention;

[0037] Figure 6 It is a partial circuit diagram of the data acquisition module provided by the present invention. DETAILED DESCRIPTION

[0038] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the protection scope of the present invention.

[0039] Example 1

[0040] Based on the research of the prior art described in the background technology, it is urgent to research and develop new monitoring technologies and equipment to achieve efficient monitoring of power supply lines without the need to dismantle or massively remodel the original lines. Solving this problem will help improve the reliability of the power supply system, reduce operating and maintenance costs, and effectively reduce the impact on the environment, thereby promoting sustainable development.

[0041] like Figure 1 As shown, this embodiment provides a method for detecting power outage of a power supply line, including:

[0042] Obtain the bus current, resistance current and capacitance current of the monitoring device connected in parallel with the arrester monitor on the power supply line;

[0043] The direction of the bus current flowing to the ground is considered positive. If the bus current is 0, the resistor current is positive, the capacitor current is negative, and the bus current is the sum of the resistor current and the capacitor current, it means that the power outage judgment condition is met and the power supply line is out of power.

[0044] The resistor current refers to the current flowing through the monitoring resistor in the monitoring device, and the capacitor current refers to the current flowing through the monitoring capacitor in the monitoring device; the monitoring resistor is connected in parallel with the monitoring capacitor.

[0045] In the power transmission and distribution network, the arrester is an important protective device, mainly used to limit the damage of lightning overvoltage and operating overvoltage to power equipment. The present invention cleverly connects a monitoring device in parallel at both ends of the original arrester monitor of the arrester, and does not need to change the original device in the arrester grounding loop during the installation process. The power supply line power failure detection method is implemented on the basis of the monitoring device, realizing automatic and rapid recognition of the power failure state.

[0046] During normal operation, the voltage of the power supply line of the power grid is usually maintained at a fixed level. Since the power supply voltage is stable, the voltage borne by the lightning arrester is basically constant. Therefore, the leakage current of a normally operating lightning arrester remains basically constant in a short period of time. This constant leakage current is determined by the characteristics of the lightning arrester and the material properties. In actual operation, although external factors such as ambient temperature and humidity may have some impact on the leakage current, these impacts are usually small and will not cause significant changes in the leakage current.

[0047] The internal resistance of the arrester monitor is much smaller than that of the arrester. The internal resistance of a normal arrester is in the tens of megohms, while the internal resistance of the arrester monitor is in the thousands of ohms. Therefore, the arrester monitor connected in series in the grounding loop has almost no effect on the size of the original arrester leakage current, which is equivalent to a constant current source with a large internal resistance passing through the arrester monitor. In the present embodiment, the internal resistance of the monitoring device is several hundred megohms. During the implementation process, 200 megohms to 300 megohms can be selected, and specifically 300 megohms is selected in the present embodiment, which is much larger than the internal resistance of the arrester monitor, which is hundreds to thousands of times its internal resistance. The monitoring device is connected in parallel to the arrester monitor, and its shunt is only a few thousandths to a few hundredths of the leakage current. The bus current of the monitoring device can be a factor of the leakage current in the arrester monitor. to In this embodiment, the magnitude of the bus current is set to the magnitude of the leakage current in the arrester monitor. , which has almost no impact on the measurement of the original arrester monitor, and the measurement error complies with relevant standards. The specific standard number is DL / T1432.3-2016, which is the inspection specification for online monitoring devices of substation equipment Part 3 Capacitive equipment and metal oxide arrester insulation online monitoring devices, and Q / GDW1537-2015, which is the technical specification for online monitoring devices of metal oxide arresters insulation. Therefore, a high internal resistance monitoring device can be connected in parallel to the arrester detector without affecting the original device. The specific connection relationship of the monitoring device is as follows: Figure 3As shown, the corresponding detection method is implemented to identify power outages in the power supply lines of the power grid. Since the overall impedance of the original lightning arrester monitor does not change much after a monitoring device is connected in parallel, the impedance change rate is less than 0.1%. In this embodiment, 0.1% is the preset impedance change rate, so there is basically no effect on the original lightning arrester grounding loop.

[0048] In this embodiment, a monitoring resistor is connected in parallel with a monitoring capacitor inside the monitoring device. In the specific implementation process, the monitoring resistor part can be a resistor group formed by connecting multiple resistors, and the same is true for the capacitor. When the power supply line operates normally, the leakage current will charge the monitoring capacitor. , where i is a vector, called bus current, and the current flowing from the bus direction to the ground direction is considered positive; i0 is a vector, called resistor current, and the current flowing from the bus direction to the monitoring resistor direction is considered positive; i1 is a vector, called capacitor current, and the current flowing from the bus direction to the monitoring capacitor direction is considered positive, and are all positive values; when the power supply line is out of power, the bus current i is 0, and the monitoring capacitor will discharge the monitoring resistor. ,and is a positive value, So according to the above power supply line power outage state The characteristics can be measured by The power supply or outage status of the power supply line can be determined by the relationship and positive and negative values. The distribution in the circuit is as follows Figure 4 As shown, Figure 4 Where R is the monitoring resistor and C is the monitoring capacitor.

[0049] The present invention does not need to change the original device of the power supply line. A monitoring device is connected in parallel to the original lightning arrester monitor. By monitoring the change of current, it is accurately determined whether the power supply line is out of power. During the installation of the equipment, the present invention does not need to change the original circuit structure of the lightning arrester grounding loop and the power supply line, and can realize automatic and rapid identification of power outages in the power supply line, avoiding technical compatibility problems, safety problems and power supply interruption problems caused by the original line modification; and it is more convenient to install and the installation time is greatly shortened.

[0050] Example 2

[0051] Based on the same inventive concept as in Example 1, Figure 2 As shown, this embodiment provides a power supply line power outage detection method, which aims to improve the safety and efficiency of power system operation and maintenance. This method does not need to change the original power supply line device, and a monitoring device is connected in parallel to the original lightning arrester monitor connected to the power supply line. By monitoring the changes of all currents inside the monitoring device, the power outage state of the power supply line can be accurately judged.

[0052] This embodiment provides a method for detecting power outages in power supply lines, and the specific implementation process is as follows:

[0053] Measure separately Figure 4 middle The size and direction of are positive and When i is 0, it means that the power outage judgment condition is met, the power supply line is operating normally, and the power supply line is not out of power; when i is 0, is positive, is negative and When , it indicates that the power outage judgment condition is met and the power supply line is in a power outage state. In other cases, the monitoring device may fail. If both the power outage judgment condition and the non-power outage judgment condition are not met at the same time, it indicates that a fault occurs inside the monitoring device, and a monitoring device fault notification is sent to the preset receiving unit. At this time, the monitoring device needs to be checked in time to ensure that the monitoring device is working normally.

[0054] like Figure 2 As shown, a power outage detection method for a power supply line provided in this embodiment can be summarized as follows:

[0055] Step 1: Set parameters inside the monitoring device ;

[0056] Step 2: Measure size and direction;

[0057] Step 3: Judgement are positive and Is it true? If it is true, it means that the power outage judgment condition is met and the power supply line is not out of power. Go to step 2. If it is not true, go to step 4.

[0058] Step 4: Judgement is 0, is positive, is negative and Is it true? If it is true, it means that the power outage judgment condition is met and the power supply line is out of power. Go to step 5. If it is not true, go to step 6.

[0059] Step 5: Determine whether the power supply line is in a power outage state and send the relevant results to the backend;

[0060] Step 6: Determine if there is a problem with the monitoring device and send the relevant results to the background.

[0061] In order to verify the detection effect of the present invention, the following experiments were performed:

[0062] Taking the 220KV transmission line as an example, the leakage current of the lightning arrester at this voltage level is 500μA. According to the shunt ratio between the monitoring device and the lightning arrester monitor, it can be concluded that the leakage current passing through the monitoring device is 0.3μA.

[0063] A current generator is used to simulate the current passing through the monitoring device, and the power supply and power failure state of the power supply circuit is simulated by controlling the on and off state of the current generator. The test data is shown in Table 1.

[0064] Table 1 - Test data table

[0065]

[0066] From the data in Table 1, it can be seen that when the power supply line starts to operate, the leakage current will charge the capacitor. As the voltage across the capacitor increases, the charging speed slows down and the capacitor current When the power supply line is out of power, the capacitor will discharge the resistor. As the discharge progresses, the voltage across the capacitor drops and the current in the resistor As it gets smaller and smaller, it can be seen from the data in the lower half of Table 1 that the detection method provided by the present invention can realize accurate and rapid identification of power outages in power supply lines.

[0067] Example 3

[0068] Based on the same inventive concept as that of Example 1, this embodiment provides a power supply line power failure detection system, including a monitoring device, a data sampling module and a data processing module, wherein the monitoring device is connected in parallel with a lightning arrester monitor on the power supply line;

[0069] The monitoring device includes a monitoring resistor and a monitoring capacitor, and the monitoring resistor and the monitoring capacitor are connected in parallel;

[0070] The data sampling module is used to collect the bus current, the resistor current and the capacitor current of the monitoring device, wherein the resistor current refers to the current flowing through the monitoring resistor, and the capacitor current refers to the current flowing through the monitoring capacitor;

[0071] The data processing module is used to execute the method provided in Example 1 or Example 2.

[0072] Example 4

[0073] like Figure 5 and Figure 6 As shown, this embodiment provides a power supply line power outage detection system. On the basis of Example 3, the resistance of the monitoring resistor is 200 megohms to 300 megohms, and the data acquisition module is used to collect the bus current, resistor current and capacitor current inside the monitoring device, which are all vectors.

[0074] The data acquisition module includes a bus current acquisition circuit, which includes a current amplifier U2, a capacitor C1, an operational amplifier U3, a capacitor C2, a capacitor C3, a resistor R3, a transient suppression diode TVS1, a diode D1, a diode D2 and a single-chip microcomputer U1. The data acquisition module also includes a resistor current acquisition circuit and a capacitor current acquisition circuit.

[0075] In this embodiment, the model of the current amplifier U2 is FP130AKR-LF, the capacitance of the capacitor C1 is 100nF, the capacitance of the capacitor C2 is 10nF, the rated voltage of the capacitor C2 is 10V, the capacitance of the capacitor C3 is 10nF, the model of the transient suppression diode TVS1 is SDT23CXXL02, the model of the diode D1 and the diode D2 is IN4148, the model of the operational amplifier U3 is AD8541ARZ, the resistance of the resistor R3 is 200kΩ, and the model of the microcontroller U1 is STM32L151RCT6.

[0076] like Figure 5 As shown, in the bus current acquisition circuit:

[0077] The non-inverting input terminal VP and the inverting input terminal VN of the current amplifier U2 are respectively connected to the bus bars at both ends of the monitoring device;

[0078] The VCC power supply terminal of the current amplifier U2 is electrically connected to the positive power supply VCC-F, and is connected in series with the capacitor C1 and then grounded; the signal output terminal of the current amplifier U2 is connected in series with the capacitor C2 and then electrically connected to the inverting input terminal of the operational amplifier U3;

[0079] The inverting input terminal of the operational amplifier U3 is connected in series with a resistor R3 and then electrically connected to the output terminal of the operational amplifier U3; a diode D1 and a diode D2 are connected in reverse parallel between the non-inverting input terminal and the inverting input terminal of the operational amplifier U3; the output terminal of the operational amplifier U3 is connected in series with a capacitor C3 and then grounded, and the output terminal of the operational amplifier U3 is also connected to the ADC sampling pin of the single-chip computer U1;

[0080] The common terminal of the current amplifier U2, the non-inverting input terminal of the operational amplifier U3, and the power supply terminal are respectively connected to a 1.6V voltage source.

[0081] The signal output terminal of the current amplifier U2 and the non-inverting input terminal of the operational amplifier U3 are respectively connected in series with a transient suppression diode TVS1 and then grounded.

[0082] Figure 5 and Figure 6 OUT in the figure represents the voltage signal output by the current amplifier U2.

[0083] When the bus current is positive, the voltage output by the current amplifier U2 is greater than 1.6V. When the bus current is negative, the voltage output by the current amplifier U2 is less than 1.6V. This is used to determine whether the bus current is positive or negative.

[0084] Capacitor C1 is a voltage-stabilizing capacitor for supplying power to current amplifier U2.

[0085] Since the bus current, the resistor current and the capacitor current are tested in the same way, only one of them is introduced in this embodiment. The measured current (since the acquisition principle of the three data acquisition modules is the same, only the bus current is described here, and the measured current in this paragraph represents the bus current) flows in the data acquisition module including: the measured current is provided to the current amplifier U2 to be amplified into a voltage signal, the measured current flows from the current input terminal VIN+ into the non-inverting input terminal VP of the current amplifier U2, and the measured current also flows from the current input terminal VIN- into the inverting input terminal VN of the current amplifier U2, that is, the current input terminal VIN+ and the current input terminal VIN- are respectively located at the two ends of the monitoring device; the measured current is amplified by the current amplifier U2 and then passes through the operational amplifier U3, and then is connected to the ADC sampling pin of the single-chip computer U1, thereby realizing data acquisition; the transient suppression diode TVS1, the diode D1 and the diode D2 play an overvoltage protection role, the capacitor C2 and the capacitor C3 filter the sampling signal, and the resistor R3 is the feedback resistor of the operational amplifier U3.

[0086] The circuit structure of the resistor current acquisition circuit is the same as that of the bus current acquisition circuit. When acquiring the resistor current, the in-phase input terminal VP and the inverting input terminal VN of the current amplifier U2 in the resistor current acquisition circuit are respectively connected to the two ends of the monitoring resistor. The judgment logic of the positive and negative of the resistor current is the same as that of the bus current.

[0087] The circuit structure of the capacitor current acquisition circuit is the same as that of the bus current acquisition circuit. When acquiring the capacitor current, the in-phase input terminal VP and the inverting input terminal VN of the current amplifier U2 in the capacitor current acquisition circuit are respectively connected to the two ends of the monitoring capacitor. The judgment logic of the positive and negative of the capacitor current is the same as that of the bus current.

[0088] In this embodiment, the positive and negative judgment method of the bus current, the resistor current and the capacitor current is as follows:

[0089] In the data acquisition module for collecting bus current, when the voltage outputted by the voltage signal output terminal of the current amplifier U2 is greater than 1.6V, the bus current is positive;

[0090] In the data acquisition module for collecting the resistor current, when the voltage outputted by the voltage signal output terminal of the current amplifier U2 is greater than 1.6V, the resistor current is positive;

[0091] In the data acquisition module for acquiring the capacitor current, when the voltage outputted by the voltage signal output terminal of the current amplifier U2 is greater than 1.6V, the capacitor current is positive.

[0092] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0093] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0094] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0095] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0096] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for detecting power outage in a power supply line, characterized in that: include: Obtain the bus current, resistance current and capacitance current of the monitoring device connected in parallel with the arrester monitor on the power supply line; The direction in which the bus current of the monitoring device flows to the ground is positive. If the bus current is 0, the resistor current is positive, the capacitor current is negative, and the bus current is the sum of the resistor current and the capacitor current, it indicates that the power outage judgment condition is met and the power supply line is in a power outage. The resistor current refers to the current flowing through the monitoring resistor in the monitoring device, and the capacitor current refers to the current flowing through the monitoring capacitor in the monitoring device; The monitoring resistor is connected in parallel with the monitoring capacitor.

2. The power supply line power outage detection method according to claim 1, characterized in that: Also includes: If the bus current, the resistor current and the capacitor current are all positive, and the bus current is the sum of the resistor current and the capacitor current, it indicates that the power outage judgment condition is met and the power supply line is not out of power.

3. The power supply line power outage detection method according to claim 2, characterized in that: Also includes: If the bus current, the resistor current and the capacitor current do not satisfy the power outage determination condition and the non-power outage determination condition at the same time, it indicates that a fault occurs inside the monitoring device, and a monitoring device fault notification is issued to a preset receiving unit.

4. The power supply line power outage detection method according to claim 1, characterized in that: The impedance change rate of the arrester monitor after being connected in parallel with the monitoring device is less than 0.1%.

5. The method for detecting power outage in a power supply line according to claim 1, characterized in that: The internal resistance of the monitoring device is 200 to 9000 times the internal resistance of the arrester monitor.

6. A power supply line power outage detection system, characterized in that: It includes a monitoring device, a data sampling module and a data processing module, wherein the monitoring device is connected in parallel with a lightning arrester monitor on a power supply line; The monitoring device comprises a monitoring resistor and a monitoring capacitor, and the monitoring resistor and the monitoring capacitor are connected in parallel; The data sampling module is used to collect the bus current, the resistor current and the capacitor current of the monitoring device, wherein the resistor current refers to the current flowing through the monitoring resistor, and the capacitor current refers to the current flowing through the monitoring capacitor; The data processing module is used to execute the method described in any one of claims 1 to 5.

7. The power supply line power outage detection system according to claim 6, characterized in that: The resistance of the monitoring resistor is 200-300 megohms.

8. The power supply line power outage detection system according to claim 6, characterized in that: The data acquisition module includes a bus current acquisition circuit; The bus current acquisition circuit includes a current amplifier U2, a capacitor C1, an operational amplifier U3, a capacitor C2, a capacitor C3, a resistor R3 and a single-chip microcomputer U1; The non-inverting input terminal VP and the inverting input terminal VN of the current amplifier U2 are respectively connected to the bus bars at both ends of the monitoring device; The VCC power supply terminal of the current amplifier U2 is electrically connected to the positive power supply VCC-F, and is connected in series with the capacitor C1 and then grounded; the signal output terminal of the current amplifier U2 is connected in series with the capacitor C2 and then electrically connected to the inverting input terminal of the operational amplifier U3; The inverting input terminal of the operational amplifier U3 is connected in series with a resistor R3 and then electrically connected to the output terminal of the operational amplifier U3; a diode D1 and a diode D2 are connected in reverse parallel between the non-inverting input terminal and the inverting input terminal of the operational amplifier U3; the output terminal of the operational amplifier U3 is connected in series with a capacitor C3 and then grounded, and the output terminal of the operational amplifier U3 is also connected to the ADC sampling pin of the single-chip computer U1; The common terminal of the current amplifier U2, the non-inverting input terminal of the operational amplifier U3, and the power supply terminal are respectively connected to a voltage source.

9. The power supply line power outage detection system according to claim 8, characterized in that: The bus current sampling circuit further includes a transient suppression diode TVS1. The signal output end of the current amplifier U2 and the in-phase input end of the operational amplifier U3 are respectively connected in series with the transient suppression diode TVS1 and then grounded.

10. The power supply line power outage detection system according to claim 8 or 9, characterized in that: The data acquisition module also includes a resistor current acquisition circuit, the circuit structure of which is the same as that of the bus current acquisition circuit. When acquiring the resistor current, the in-phase input terminal VP and the inverting input terminal VN of the current amplifier U2 in the resistor current acquisition circuit are respectively connected to the two ends of the monitoring resistor; or, The data acquisition module also includes a capacitor current acquisition circuit, the circuit structure of which is the same as that of the bus current acquisition circuit. When collecting the capacitor current, the in-phase input terminal VP and the inverting input terminal VN of the current amplifier U2 in the capacitor current acquisition circuit are respectively connected to the two ends of the monitoring capacitor.

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