A lightning arrester current sharing monitoring device and method in a controllable self-restoring energy dissipation device

Abstract

The present invention discloses a device and method for monitoring the uniform current of lightning arresters in a controllable self-restoring energy dissipation device, wherein the device includes: a plurality of branch current measuring device electromagnetic current transformers, a data acquisition module, and a control and protection module; the plurality of branch current measuring device electromagnetic current transformers respectively correspond to the lightning arrester body and are arranged at the connection between the fixed element and the controlled element of the lightning arrester body to measure the operating current of each lightning arrester body and determine its uniformity; the data acquisition module obtains the measurement signal of the branch current measuring device electromagnetic current transformer and sends it to the control and protection module; the control and protection module performs real-time detection of the uniformity of the operating current of the lightning arrester body based on the measurement signal sent by the data acquisition module. Compared with the traditional lightning arrester uniform current monitoring solution, the device reduces the difficulty of insulation design, floor space occupied, and equipment cost, ensures measurement accuracy, improves equipment reliability, and further enhances the stability of the power grid system.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage power equipment measurement, and in particular to a device and method for monitoring the current sharing of a lightning arrester in a controllable self-restoring energy dissipation device. Background Art

[0002] When bipolar DC faults (bipolar commutation failure, bipolar blocking, or bipolar line restart) occur in a high-power grid system, the AC system and AC filters generate excessive reactive power during the DC power interruption, causing transient overvoltages at the converter station that exceed system control levels. This is a major issue in limiting DC power. Controllable self-restoring energy dissipation devices, installed between the AC busbars of the converter station, effectively address these grid system overvoltage issues.

[0003] When the power grid system is operating normally, the fixed and controlled components of the arrester in the controllable self-restoring energy dissipation device exhibit high resistance, allowing only leakage current to flow. However, because the arrester resistors are directly exposed to the operating voltage for long periods of time and are subjected to various overvoltages and surge currents during operation, if the resistors become damp and age, they can easily break down and cause a short circuit, potentially causing a major power grid accident. Therefore, promptly detecting potential arrester failures before they become serious accidents is crucial to preventing them from escalating into accidents.

[0004] To accurately and reliably determine the quality of a lightning arrester, it is necessary to perform condition monitoring. The main operating parameters monitored include operating current, leakage current, and surface contamination. However, current arrester current measurement devices are bulky, experience significant losses, and are expensive, making them unsuitable for monitoring the shared current of multiple parallel arresters in controllable, self-restoring energy dissipation devices used in AC systems. Summary of the Invention

[0005] The purpose of the embodiment of the present invention is to provide a lightning arrester current sharing monitoring device and method in a controllable self-restoring energy dissipation device. The uniformity of the lightning arrester operating current is monitored by an electromagnetic current transformer, a branch current measuring device, which is arranged between the fixed part and the controllable part of the lightning arrester. Compared with the traditional lightning arrester current sharing monitoring scheme, it can not only reduce the difficulty of insulation design, but also reduce the floor space and equipment cost. While ensuring measurement accuracy, it can realize the operating current measurement of each lightning arrester and perform uniformity monitoring; it can also improve equipment reliability and further enhance the stability of the power grid system.

[0006] To solve the above technical problems, an embodiment of the present invention provides a lightning arrester current sharing monitoring device in a controllable self-restoring energy dissipation device, comprising: a plurality of branch current measuring devices, electromagnetic current transformers, a data acquisition module, and a control and protection module;

[0007] The electromagnetic current transformers of the branch current measuring devices correspond to the arrester bodies respectively and are arranged at the connection between the fixed element and the controlled element of the arrester body to measure the operating current of each arrester body and determine its uniformity;

[0008] The data acquisition module acquires the measurement signal of the electromagnetic current transformer of the branch current measurement device and sends it to the control and protection module;

[0009] The control and protection module performs real-time detection on the uniformity of the operating current of the arrester body according to the measurement signal sent by the data acquisition module.

[0010] Furthermore, the electromagnetic current transformer of the branch current measuring device outputs two measurement signals, and the two measurement signals are respectively transmitted to the data acquisition unit.

[0011] Furthermore, the data acquisition unit is provided with two power inputs, performs high-speed AD sampling on the two measurement signals of each arrester body measurement point, and outputs them to the control and protection module simultaneously through two mutually redundant optical signals.

[0012] Furthermore, the high-speed AD sampling transmits the measurement signal through an optical fiber.

[0013] Furthermore, the optical signal adopts the standard IEC60044-8 communication protocol.

[0014] Furthermore, the arrester current sharing monitoring device in the controllable self-restoring energy dissipation device further includes: an energy supply transformer;

[0015] The data acquisition unit is arranged on a high-potential insulating platform and is supplied with electric energy by the energy supply transformer.

[0016] Furthermore, the secondary voltage of the energy supply transformer is at the same potential as the insulation platform of the controllable self-restoring energy dissipation device.

[0017] Accordingly, a second aspect of an embodiment of the present invention provides a method for monitoring the current sharing of a lightning arrester in a controllable self-restoring energy dissipation device, wherein the lightning arrester in the controllable self-restoring energy dissipation device is monitored by any of the above-mentioned devices for monitoring the current sharing of a lightning arrester in the controllable self-restoring energy dissipation device, comprising the following steps:

[0018] Acquiring an operating current measurement signal at a connection between a fixed element and a controlled element of the arrester body based on an electromagnetic current transformer of a branch current measurement device;

[0019] Based on the data acquisition module, the operating current measurement signal of the arrester body is received and sent to the control and protection module;

[0020] The operating current measurement signal of the arrester body is analyzed by the control and protection module to obtain a real-time detection result of the operating current of the arrester body.

[0021] The above technical solutions of the embodiments of the present invention have the following beneficial technical effects:

[0022] The uniformity of the arrester's operating current is monitored by using an electromagnetic current transformer, a branch current measuring device installed between the fixed and controllable parts of the arrester. Compared with traditional arrester current sharing monitoring solutions, this solution can not only reduce the difficulty of insulation design, but also reduce the floor space and equipment cost. While ensuring measurement accuracy, it can measure the operating current of each arrester and monitor its uniformity. It can also improve equipment reliability and further enhance the stability of the power grid system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a configuration diagram of the current sharing monitoring configuration of the lightning arrester in the controllable self-restoring energy dissipation device provided by an embodiment of the present invention;

[0024] Figure 2 The present invention provides a wiring diagram of a lightning arrester branch current measuring device. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0026] Please refer to Figure 1 and Figure 2 , an embodiment of the present invention provides a lightning arrester current sharing monitoring device in a controllable self-recovering energy dissipation device.

[0027] The arrester body includes: fixed elements and controlled elements, both of which are multi-column parallel-connected. The fixed elements and controlled elements are connected in series with the same number of columns; the voltage-equalizing capacitor is connected in parallel at both ends of the fixed elements to ensure uniform voltage distribution between the fixed elements and the controlled elements; the control switch is connected in parallel at both ends of the controlled element. When a fault occurs in the AC system, the controlled element is partially bypassed to reduce the residual voltage of the arrester.

[0028] The lightning arrester current sharing monitoring device in the controllable self-restoring energy dissipation device includes: several branch current measuring device electromagnetic current transformers, a data acquisition module and a control and protection module; several branch current measuring device electromagnetic current transformers correspond to the lightning arrester body respectively, and are arranged at the connection between the fixed element and the controlled element of the lightning arrester body to measure the operating current of each lightning arrester body and judge its uniformity; the data acquisition module obtains the measurement signal of the branch current measuring device electromagnetic current transformer and sends it to the control and protection module; the control and protection module performs real-time detection of the uniformity of the operating current of the lightning arrester body based on the measurement signal sent by the data acquisition module.

[0029] Specifically, the electromagnetic current transformer of the branch current measuring device outputs two measurement signals, and the two measurement signals are respectively transmitted to the data acquisition unit.

[0030] Specifically, the data acquisition unit is provided with two power inputs, performs high-speed AD sampling on the two measurement signals of each arrester body measurement point, and outputs them to the control and protection module simultaneously through two mutually redundant optical signals.

[0031] Optionally, high-speed AD sampling transmits the measurement signal via optical fiber.

[0032] Preferably, the optical signal adopts the standard IEC60044-8 communication protocol.

[0033] In addition, the arrester current sharing monitoring device in the controllable self-restoring energy dissipation device also includes: an energy supply transformer; a data acquisition unit is arranged on a high-potential insulating platform, and electric energy is provided by the energy supply transformer.

[0034] Furthermore, the secondary voltage of the energy supply transformer is at the same potential as the insulation platform of the controllable self-restoring energy dissipation device.

[0035] like Figure 1 As shown in the figure, the specific working process of the arrester current sharing monitoring in the controllable self-restoring energy dissipation device is as follows:

[0036] When the power grid operates normally, the AC bus voltage is stable, the control switch in the controllable self-restoring energy dissipation device is in the open state, and the arrester's fixed and controlled components exhibit high resistance, allowing only leakage current to flow. The arrester leakage current is measured by a branch electromagnetic current transformer and sampled at high speed by a data acquisition unit powered by the energy transformer. The sampled data is then transmitted via optical fiber to the control and protection system, enabling measurement and monitoring of the arrester leakage current.

[0037] When the power grid experiences fault conditions such as single-pole lockout, double-pole lockout, or continuous commutation failure, the control and protection system detects that system parameters meet the conditions for the controllable self-recovery energy dissipation device to be put into operation and immediately issues a closing command to the control switch. Upon receiving the closing command, the control switch closes, bypassing the controlled element of the lightning arrester. At this time, the lightning arrester operating current is measured by a branch electromagnetic current transformer and sampled at high speed by a data acquisition unit powered by the energy transformer. After sampling, the data is transmitted to the control and protection system via optical fiber, realizing the measurement of the lightning arrester operating current and uniformity monitoring.

[0038] Accordingly, a second aspect of an embodiment of the present invention provides a method for monitoring the current sharing of a lightning arrester in a controllable self-restoring energy dissipation device, wherein the lightning arrester in the controllable self-restoring energy dissipation device is monitored by any of the above-mentioned lightning arrester current sharing monitoring devices in the controllable self-restoring energy dissipation device, comprising the following steps:

[0039] Step S100: obtaining an operating current measurement signal at a connection point between a fixed element and a controlled element of a lightning arrester body based on an electromagnetic current transformer of a branch current measurement device.

[0040] Step S200: The data acquisition module receives the operating current measurement signal of the arrester body and sends it to the control and protection module.

[0041] Step S300: analyzing the operating current measurement signal of the arrester body through the control protection module to obtain a real-time detection result of the operating current of the arrester body.

[0042] The embodiment of the present invention aims to protect a lightning arrester current sharing monitoring device and method in a controllable self-restoring energy dissipation device, wherein the device includes: a plurality of branch current measuring device electromagnetic current transformers, a data acquisition module and a control protection module; a plurality of branch current measuring device electromagnetic current transformers respectively correspond to the lightning arrester body, which are arranged at the connection between the fixed element and the controlled element of the lightning arrester body to measure the action current of each lightning arrester body and judge its uniformity; the data acquisition module obtains the measurement signal of the branch current measuring device electromagnetic current transformer and sends it to the control protection module; the control protection module performs real-time detection of the action current uniformity of the lightning arrester body based on the measurement signal sent by the data acquisition module. The above technical solution has the following effects:

[0043] The uniformity of the arrester's operating current is monitored by using an electromagnetic current transformer, a branch current measuring device installed between the fixed and controllable parts of the arrester. Compared with traditional arrester current sharing monitoring solutions, this solution can not only reduce the difficulty of insulation design, but also reduce the floor space and equipment cost. While ensuring measurement accuracy, it can measure the operating current of each arrester and monitor its uniformity. It can also improve equipment reliability and further enhance the stability of the power grid system.

[0044] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A lightning arrester current sharing monitoring device in a controllable self-restoring energy dissipation device, characterized in that: include: Several branch current measurement devices, electromagnetic current transformers, data acquisition units and control and protection modules; The electromagnetic current transformers of the branch current measuring devices correspond to the arrester bodies respectively and are arranged at the connection between the fixed element and the controlled element of the arrester body to measure the operating current of each arrester body and determine its uniformity; The data acquisition unit acquires the measurement signal of the electromagnetic current transformer of the branch current measurement device and sends it to the control and protection module; The control and protection module performs real-time detection of the operating current uniformity of the arrester body according to the measurement signal sent by the data acquisition unit; The electromagnetic current transformer of the branch current measuring device outputs two measurement signals, and the two measurement signals are respectively transmitted to the data acquisition unit; The data acquisition unit is provided with two power inputs, performs high-speed AD sampling on the two measurement signals of each arrester body measurement point, and outputs them to the control and protection module simultaneously through two mutually redundant optical signals; The high-speed AD sampling transmits the measurement signal through an optical fiber.

2. The arrester current sharing monitoring device in the controllable self-restoring energy dissipation device according to claim 1 is characterized in that: The optical signal adopts the standard IEC60044-8 communication protocol.

3. The arrester current sharing monitoring device in the controllable self-restoring energy dissipation device according to claim 1 or 2, characterized in that: Also includes: Energy supply transformer; The data acquisition unit is arranged on a high-potential insulating platform and is supplied with electric energy by the energy supply transformer.

4. The arrester current sharing monitoring device in the controllable self-restoring energy dissipation device according to claim 3 is characterized in that: The secondary voltage of the energy supply transformer is at the same potential as the insulation platform of the controllable self-restoring energy dissipation device.

5. A method for monitoring the current sharing of a lightning arrester in a controllable self-restoring energy dissipation device, characterized in that: Monitoring the arrester in the controllable self-restoring energy dissipation device by the arrester current sharing monitoring device in the controllable self-restoring energy dissipation device according to any one of claims 1 to 4 comprises the following steps: Acquiring an operating current measurement signal at a connection between a fixed element and a controlled element of the arrester body based on an electromagnetic current transformer of a branch current measurement device; Based on the data acquisition unit, the operating current measurement signal of the arrester body is received and sent to the control and protection module; The operating current measurement signal of the arrester body is analyzed by the control and protection module to obtain a real-time detection result of the operating current of the arrester body.

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