Lightning arrester leakage current on-line monitoring device

Abstract

The utility model discloses a lightning arrester leakage current on-line monitoring device which comprises an on-line monitoring device main body, a sampling unit is arranged in the on-line monitoring device main body, the input end of the sampling unit is electrically connected with a plurality of current sensors, each current sensor is electrically connected with a lightning arrester, the output end of the sampling unit is electrically connected with a CPU, and the CPU is electrically connected with the on-line monitoring device main body. The output end of the CPU is electrically connected with an output unit, the current sensor is a zero-flux sensor and improves the measurement precision of the current of the lightning arrester, the sampling unit comprises a filter and is used for filtering disordered signals and further improving the measurement precision, the input end of the filter is electrically connected with the current sensor, and the output end of the filter is electrically connected with an analog switch. And multi-channel transmission of measurement signals is realized. According to the utility model, through the arrangement of corresponding mechanisms, live-line online monitoring can be carried out on the lightning arrester, so that workers can conveniently and timely master the actual operation condition of the lightning arrester, and the inspection work of the lightning arrester is completed.

Description

Technical Field

[0001] This utility model belongs to the field of online monitoring technology, specifically relating to an online monitoring device for leakage current of surge arresters. Background Technology

[0002] With the development of online monitoring, pattern recognition, and computer information processing technologies, the shift from planned maintenance to condition-based maintenance of electrical equipment has become an inevitable trend. High-voltage electrical equipment is the foundation supporting the safe operation of substations and the entire power system, and is an indispensable and important component of high-voltage power distribution systems. To ensure the safety and reliability of power system operation, installing online monitoring equipment on high-voltage equipment within substations allows for real-time monitoring of the equipment's operation, providing early warnings of anomalies and thus preventing serious losses from sudden failures.

[0003] Online monitoring systems for high-voltage equipment in substations can monitor main transformers, surge arresters, and high-voltage circuit breakers online. Surge arresters are crucial for ensuring the safe operation of the power system. However, surge arresters, subjected to the system's operating voltage for extended periods, can gradually crack or become damp due to poor structure or inadequate sealing, leading to damage or even explosion. This can cause busbar short circuits and compromise system safety. Furthermore, surge arrester inspections require the shutdown of main equipment, which is sometimes impossible due to operational limitations, especially for high-voltage equipment. This prevents timely surge arrester testing.

[0004] Therefore, in order to address the aforementioned technical problems, it is necessary to provide an online monitoring device for surge arrester leakage current. Utility Model Content

[0005] The purpose of this invention is to provide an online monitoring device for surge arrester leakage current to solve the problem of surge arresters not being able to be inspected on time.

[0006] To achieve the above objectives, the technical solution provided by an embodiment of this utility model is as follows:

[0007] An online monitoring device for leakage current of a surge arrester includes an online monitoring device body. The online monitoring device body is provided with a sampling unit. The input terminal of the sampling unit is electrically connected to a plurality of current sensors, and each current sensor is electrically connected to a surge arrester. The output terminal of the sampling unit is electrically connected to a CPU, and the output terminal of the CPU is electrically connected to an output unit.

[0008] Furthermore, the current sensor is a zero-flux sensor, which improves the measurement accuracy of the surge arrester current.

[0009] Furthermore, the sampling unit includes a filter for filtering out cluttered signals, thereby improving measurement accuracy. The input of the filter is electrically connected to the current sensor, and the output of the filter is electrically connected to an analog switch, enabling multi-channel transmission of the measurement signal and ensuring overall measurement accuracy.

[0010] Furthermore, the output terminal of the analog switch is electrically connected to several signal channels to improve the overall measurement accuracy. The output terminals of the several signal channels are electrically connected to an error correction unit, which is electrically connected to the CPU to reduce measurement errors and ensure the overall measurement accuracy, thereby ensuring the accuracy of online monitoring of the surge arrester.

[0011] Furthermore, the number of the current sensor and the number of the signal channels are both three.

[0012] Furthermore, an ADC amplifier is electrically connected between the error correction unit and the CPU, which enables better signal transmission.

[0013] Furthermore, the output unit includes an alarm, a display, and a communication unit. The communication unit is electrically connected to the control center via RS485, enabling digital transmission and effectively solving the problem of distortion during analog signal sensing.

[0014] Furthermore, the output terminal of the communication unit is electrically connected to an electromagnetic shielding unit, which effectively shields against electric and magnetic field interference, ensuring data transmission performance and enabling staff to accurately obtain online monitoring data of the surge arrester.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] This utility model, through the setting of a corresponding mechanism, can perform live online monitoring of surge arresters, thereby facilitating staff to promptly grasp the actual operating status of surge arresters and complete surge arrester inspection work. Attached Figure Description

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

[0018] Figure 1 This is a schematic diagram of the structure of an online monitoring device for leakage current of a surge arrester according to one embodiment of the present invention;

[0019] Figure 2Schematic diagram of the sampling unit structure in an embodiment of the present utility model;

[0020] Figure 3 3D view of an on-line monitoring device for arrester leakage current in an embodiment of the present utility model.

[0021] In the figure: 1. Main body of the on-line monitoring device, 2. Display. Specific embodiments

[0022] The present utility model will be described in detail below in conjunction with the embodiments shown in the drawings. However, these embodiments do not limit the present utility model, and any structural, method or functional transformation made by those of ordinary skill in the art based on these embodiments is included in the protection scope of the present utility model.

[0023] The present utility model discloses an on-line monitoring device for arrester leakage current. Refer Figures 1-3 As shown, it includes a main body 1 of the on-line monitoring device. Inside the main body 1 of the on-line monitoring device, there are a sampling unit, a CPU and an output unit.

[0024] Preferably, the operating temperature range of the main body 1 of the on-line monitoring device is from -20°C to +70°C, the power supply is AC220V / 50Hz, the resolution is 1dB, and the protection level is IP65.

[0025] Among them, the main body 1 of the on-line monitoring device can be installed by means of a hoop, which is convenient for subsequent maintenance by staff on the main body 1 of the on-line monitoring device.

[0026] Refer Figures 1-3 As shown, several current sensors are electrically connected to the input end of the sampling unit, and each current sensor is electrically connected to an arrester, for real-time monitoring of the full current, 3rd harmonic current, resistive current and lightning strike count of the arrester under operating conditions.

[0027] Preferably, the current sensor is a zero-flux sensor. The measurement range of the zero-flux sensor is 0.1 - 650 mA, the resolution is 10 μA, and the error rate is 10 μA, which improves the measurement accuracy of the arrester current. <00​​​​In addition, the output end of the analog switch is electrically connected to several signal channels for improving the overall measurement accuracy. The output ends of the several signal channels are electrically connected to an error correction unit, and the error correction unit is electrically connected to the CPU, which is used to reduce the measurement error and ensure the overall measurement accuracy, thereby ensuring the accuracy of the on-line monitoring of the lightning arrester.

[0030] Preferably, the number of current sensors and signal channels is three each. The sampling rate of the sampling unit is 200KHz / s.

[0031] Specifically, the CPU is electrically connected to the output end of the sampling unit, and the output unit is electrically connected to the output end of the CPU. The lightning arrester current signal collected by the sampling unit will be transmitted to the CPU, and the CPU will send the corresponding data to the output unit after analysis.

[0032] In addition, an ADC amplifier is also electrically connected between the error correction unit and the CPU, enabling better signal transmission.

[0033] See Figures 1-3 As shown, the output unit includes an alarm, a display 2, and a communication unit. The communication unit is electrically connected to a control center through RS485, enabling digital transmission and effectively solving the problem of signal distortion during the analog signal sensing process.

[0034] If an abnormal situation is detected, the alarm will give an alarm, the display 2 is convenient for the staff to read the data, and the communication unit is used to send relevant data to the control center for the staff to perform relevant processing.

[0035] Among them, the output end of the communication unit is electrically connected to an electromagnetic shielding unit, which effectively shields electric and magnetic field interference, ensures the data transmission effect, and thus enables the staff to accurately obtain the on-line monitoring data of the lightning arrester.

[0036] During specific use, the current sensor senses the pulse signal of the lightning strike discharge of the lightning arrester for lightning strike counting and event recording. The current signal fed back by the current sensor is sent to the filter, and then transmitted through multiple signal channels by the analog switch, and finally sent to the ADC amplifier through the error correction unit. After the ADC amplifier amplifies and the ADC processes and transforms it into a digital signal, the full current, third harmonic current, and resistive current of the lightning arrester are obtained through the CPU.

[0037] The CPU processes and stores the obtained data to monitor the leakage current of the lightning arrester. When a fault of the lightning arrester is detected, the alarm gives an alarm to remind the staff that the lightning arrester has a fault and needs to be replaced in time. The data can be transmitted to the control center through the communication unit, facilitating the staff to know in time.

[0038] From the above technical solutions, it can be seen that the present utility model has the following beneficial effects:

[0039] This utility model, through the setting of a corresponding mechanism, can perform live online monitoring of surge arresters, thereby facilitating staff to promptly grasp the actual operating status of surge arresters and complete surge arrester inspection work.

[0040] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0041] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An online monitoring device for leakage current of a surge arrester, comprising an online monitoring device body (1), characterized in that, The main body (1) of the online monitoring device is equipped with a sampling unit. The input end of the sampling unit is electrically connected to several current sensors. Each current sensor is electrically connected to a surge arrester. The output end of the sampling unit is electrically connected to a CPU. The output end of the CPU is electrically connected to an output unit.

2. The online monitoring device for leakage current of a surge arrester according to claim 1, characterized in that, The current sensor is a zero flux sensor.

3. The online monitoring device for leakage current of a surge arrester according to claim 1, characterized in that, The sampling unit includes a filter, the input of which is electrically connected to the current sensor, and the output of which is electrically connected to an analog switch.

4. The online monitoring device for leakage current of a surge arrester according to claim 3, characterized in that, The analog switch output terminal is electrically connected to several signal channels, and the output terminals of the several signal channels are electrically connected to an error correction unit, which is electrically connected to the CPU.

5. The online monitoring device for leakage current of a surge arrester according to claim 4, characterized in that, The number of current sensors and signal channels are both three.

6. The online monitoring device for leakage current of a surge arrester according to claim 4, characterized in that, An ADC amplifier is electrically connected between the error correction unit and the CPU.

7. The online monitoring device for leakage current of a surge arrester according to claim 1, characterized in that, The output unit includes an alarm, a display (2), and a communication unit, which is electrically connected to the control center via RS485.

8. The online monitoring device for leakage current of a surge arrester according to claim 7, characterized in that, The communication unit output is electrically connected to an electromagnetic shielding unit.

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