A high-voltage live display for GIS

Abstract

The application provides a high-voltage live display for GIS, comprising: an outer shell made of aluminum-zinc-coated sheet material for attenuating external magnetic field interference; an inner shell made of aluminum alloy sheet material, which is located in the outer shell for suppressing electric field interference; an electronic circuit arranged in the inner shell; and a copper foil tape for sealing the joint between the outer shell and the inner shell to prevent interference signals from entering the interior through the gap; wherein the electronic circuit comprises a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit and a live display circuit; the magnetic bead is used for filtering out ultra-high frequency interference signals in conducted interference; the magnetic ring is used for filtering out ultra-high frequency interference signals in conducted interference; the inductor is used for filtering out low frequency interference signals in conducted interference; the overvoltage protection circuit is used for suppressing transient overvoltage introduced through the wire; and the live display circuit is used for displaying the live state of the electrical equipment inside the GIS and providing an intuitive safety indication. The high-voltage live display can simultaneously realize effective shielding of conducted radiation and space radiation.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a high-voltage live indicator for GIS. Background Art

[0002] GIS (Gas Insulated Switchgear) is the abbreviation for gas-insulated switchgear. GIS consists of circuit breakers, disconnectors, earthing switches, transformers, lightning arresters, busbars, connectors, and outgoing line terminals. These devices or components are all enclosed in a grounded metal casing filled with SF6 insulating gas at a certain pressure. Hence, it is also called SF6 fully enclosed switchgear.

[0003] Due to the enclosed structure of the GIS, it's impossible to visually determine the live state of internal electrical equipment. Operating a GIS while it's live is extremely dangerous, posing a significant threat to the lives of workers and easily leading to accidents. Currently, live displays widely used in power systems primarily utilize a capacitor core to extract a certain voltage from the high-voltage live circuit as a power source for display and locking. This displays the live state at the device's location and can also force switches to lock. High-voltage live displays play a crucial role in indicating whether electrical equipment is operating at voltage and providing mandatory electrical locking capabilities.

[0004] GIS typically operates at high voltage levels (110kV and above), inherently subject to strong electromagnetic interference. When a circuit breaker is actuated, currents ranging from tens to hundreds of kA flow, generating extremely strong electromagnetic interference within and around the GIS's enclosed structure. The levels far exceed those specified by current national standards. Conventional high-voltage live displays are prone to display anomalies and damage in this strong electromagnetic environment, leading to misjudgment by maintenance personnel, serious safety hazards, and even fatalities.

[0005] GIS can be exposed to two types of strong electromagnetic interference: conducted radiation and space radiation. Because the GIS's high-voltage live indicator is directly connected to the GIS's primary circuit via a high-voltage capacitive sensor, a direct conduction path exists, resulting in severe exposure to conducted radiation. Furthermore, the high-voltage live indicator is installed in the GIS control terminal box, very close to the GIS itself. Switching within the GIS generates extremely strong space radiation, which can easily affect the high-voltage live indicator's operation.

[0006] Therefore, it is necessary to develop a GIS-specific high-voltage live display that is resistant to high-intensity electromagnetic interference for special application scenarios such as GIS, and at the same time achieve effective shielding of conducted radiation and space radiation. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a high-voltage live display for GIS, which can achieve effective shielding of conducted radiation and space radiation.

[0008] In order to solve the above technical problems, an embodiment of the present invention provides a high-voltage live indicator for GIS, comprising:

[0009] The shell is made of aluminum-zinc sheet material to attenuate external magnetic field interference;

[0010] An inner shell made of aluminum alloy plate, located inside the outer shell, for suppressing electric field interference;

[0011] an electronic circuit disposed in the inner housing; and

[0012] Copper foil tape is used to seal the joints between the outer shell and the inner shell to prevent interference signals from entering the interior through the gap;

[0013] Wherein, the electronic circuit includes a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit and a charged display circuit which are electrically connected in sequence;

[0014] The magnetic beads are used to filter out ultra-high frequency interference signals in conducted interference;

[0015] The magnetic ring is used to filter out ultra-high frequency interference signals in the conducted interference;

[0016] The inductor is used to filter out low-frequency interference signals in the conducted interference;

[0017] The overvoltage protection circuit is used to suppress transient overvoltages introduced through the wires;

[0018] The live display circuit is used to display the live status of electrical equipment inside the GIS, providing intuitive safety instructions.

[0019] Furthermore, the magnetic beads are installed in direct series, and the operating frequency of the magnetic beads is between 500kHz and 1MHz.

[0020] Furthermore, the magnetic ring is installed in a winding manner, and the wire that introduces the high-voltage signal is wound around the magnetic ring for multiple turns.

[0021] Furthermore, the magnetic ring is a low-frequency magnetic ring with an operating frequency between 30kHz and 300kHz.

[0022] Furthermore, the inductors are installed in direct series.

[0023] The embodiments of the present invention have the following beneficial effects:

[0024] (1) Since the display is directly connected with the primary circuit of the GIS through the high-voltage capacitive sensor, there is a direct conduction path, which is easily affected by the conduction radiation. Therefore, the magnetic beads, the magnetic ring and the inductor and other elements in the electronic circuit of the embodiment of the present application effectively filter out the conduction interference.

[0025] (2) The high-voltage live display is installed in the GIS control terminal box, close to the GIS body, and is easily affected by the strong space radiation generated when the switch in the GIS body is operated. Therefore, the electromagnetic shielding design of the embodiment of the present application has the aluminum-zinc plate material with good magnetic field attenuation effect, the aluminum alloy plate material with good electrical conductivity can inhibit the electric field interference caused by the change of the magnetic field, the copper foil tape with good ductility is used to seal the gap between the outer shell and the inner shell, so as to avoid the interference with shorter wavelength from entering the GIS high-voltage live display through the air, and effectively filter out the space radiation interference. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings obtained according to these drawings without creative labor still belong to the scope of the present application.

[0027] Figure 1 FIG. 1 is a structural schematic diagram of a GIS high-voltage live display according to an embodiment of the present application.

[0028] In the figure, 1 is an outer shell, 2 is an inner shell, 3 is a copper foil tape, 4 is a magnetic bead, 5 is a magnetic ring, 6 is an inductor, 7 is an overvoltage protection circuit, and 8 is a live display circuit. DETAILED DESCRIPTION

[0029] The detailed description of the drawings is intended as a description of the current embodiments of the present application, and is not intended to represent the only form in which the present application can be implemented. It should be understood that the same or equivalent functions can be completed by different embodiments intended to be included in the spirit and scope of the present application.

[0030] Reference Figure 1 The embodiment of the present application provides a GIS high-voltage live display, which comprises:

[0031] The outer shell made of aluminum-zinc plate material is used to attenuate external magnetic field interference;

[0032] The inner shell made of aluminum alloy plate material is located in the outer shell and is used to suppress electric field interference;

[0033] The electronic circuit arranged in the inner shell; and

[0034] Copper foil tape for sealing the joint between the outer shell and the inner shell, preventing interference signals from entering the interior through the gap;

[0035] The electronic circuit includes a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit, and a live display circuit connected in sequence.

[0036] The magnetic bead is used to filter out ultra-high frequency interference signals in conducted interference;

[0037] The magnetic ring is used to filter out ultra-high frequency interference signals in conducted interference;

[0038] The inductor is used to filter out low frequency interference signals in conducted interference;

[0039] The overvoltage protection circuit is used to suppress transient overvoltage from the wire;

[0040] The live display circuit is used to display the live state of the electrical equipment inside the GIS, providing an intuitive safety indication.

[0041] Specifically, the GIS high-voltage bus carries high voltage, and three-phase high-voltage sensors (also known as voltage transformers or PTs) are used to convert the high-voltage signal on the high-voltage bus into a safe low-voltage electrical signal. These sensors have high precision and high reliability, and can adapt to the harsh environment inside the GIS. The converted low-voltage electrical signal is connected to the terminals of the GIS-specific high-voltage live display through a dedicated cable. These terminals are designed to receive low-voltage signals from high-voltage sensors and are part of the display's electronic circuit. The terminals of the high-voltage live display are directly connected to the magnetic bead, which serves as the first filtering element in the circuit, filtering out ultra-high frequency interference signals in conducted interference.

[0042] In GIS (Gas Insulated Switchgear) systems, high-voltage live displays play a crucial role in providing critical live state indications to maintenance personnel, ensuring safe operation. However, due to the compact layout and high-voltage characteristics of GIS equipment, there is extremely strong electromagnetic field radiation interference around the display. These disturbances have high frequencies and short wavelengths, posing challenges to the normal operation of the display. To address these challenges, the GIS high-voltage live display of the present embodiment has the following special treatment on the shell structure:

[0043] Aluminum-zinc clad sheet is a material with excellent electromagnetic shielding performance, which can effectively attenuate the magnetic field strength in high-frequency electromagnetic fields. Compared with traditional stainless steel materials, aluminum-zinc clad sheet has better magnetic field attenuation effect. Although stainless steel is strong, its shielding effect on the magnetic field is not as good as that of aluminum-zinc clad sheet. Therefore, in a strong electromagnetic interference environment, aluminum-zinc clad sheet is a more suitable choice. The aluminum-zinc clad sheet shell forms a protective layer, reducing the influence of external electromagnetic fields on the internal electronic circuit.

[0044] The aluminum alloy plate has excellent electrical conductivity, which can form an equipotential surface, effectively suppressing the electric field interference generated on the inner shell surface due to the change of the magnetic field. The design of this equipotential surface helps to guide and disperse the induced current generated by the change of the external electromagnetic field, reducing the influence of electric field interference on electronic circuits.

[0045] At the joint of the outer shell and the inner shell, due to manufacturing and assembly reasons, there are some gaps inevitably. These gaps can become a channel for high-frequency electromagnetic waves to enter the display. Using a copper foil tape with good ductility to seal these gaps can effectively block the propagation path of high-frequency electromagnetic waves. The copper foil tape not only has good electrical conductivity, but also can tightly fit the gap, ensuring the integrity of electromagnetic shielding. This sealing measure is particularly important for shorter wavelength interference, because short-wavelength electromagnetic waves are more likely to enter the interior of the device through tiny gaps.

[0046] Through the above special treatment, the GIS high-voltage live display can maintain stable working performance in a strong electromagnetic interference environment, ensuring the accuracy and reliability of the display, thereby providing strong protection for the safe operation of the power system.

[0047] In the design of GIS high-voltage live display, conducted interference is a problem that needs special attention, because the display is connected to the high-voltage capacitor sensor through a wire, directly exposed to conducted interference. In order to ensure the accuracy and stability of the display, various components are used in the electronic circuit to filter out interference signals of different frequency ranges, and the functions of these components are described in detail as follows:

[0048] The magnetic bead is a commonly used component for suppressing electromagnetic interference, which is particularly effective for ultra-high frequency interference signals. The internal structure of the magnetic bead can generate additional resistance when high-frequency signals pass through, thereby consuming the energy of these signals and converting them into heat energy. In the GIS high-voltage live display, magnetic beads are used to filter out ultra-high frequency components in conducted interference, which may come from rapid voltage changes during GIS operation or other high-frequency electromagnetic sources. Through the filtering action of the magnetic bead, the electronic circuit can be protected from ultra-high frequency interference, ensuring the clarity and accuracy of signal transmission.

[0049] The magnetic ring is similar to the magnetic bead and is also used to filter high-frequency interference. The magnetic ring is usually used to wind the wire, forming a low-impedance path specifically for high-frequency signals. In the GIS high-voltage live display, the magnetic ring is used to further filter out ultra-high frequency signals in conducted interference. By winding the wire around the magnetic ring multiple times, the filtering effect can be enhanced. The selection of the magnetic ring is usually based on its working frequency range, and the magnetic ring mentioned in this invention has a working frequency of 30kHz-300kHz, which covers the high-frequency interference that may occur during GIS operation.

[0050] An inductor is a component that suppresses low-frequency interference signals. Its inductance creates impedance for low-frequency signals, thereby reducing their impact on electronic circuits. In GIS high-voltage live displays, inductors are used to filter out low-frequency components of conducted interference, which can originate from the power system's fundamental frequency and harmonics. Inductors are typically installed directly in series to effectively suppress low-frequency interference signals before they enter the electronic circuits.

[0051] Overvoltage protection circuits are an integral part of electronic circuits. They suppress transient overvoltages introduced through wires, protecting electronic components from damage. In GIS high-voltage live displays, overvoltage protection circuits quickly respond and limit the magnitude of overvoltages, ensuring that electronic circuits are not damaged by voltage anomalies.

[0052] Through the integrated application of these electronic circuit components, the GIS high-voltage live display effectively filters out conducted interference, including ultra-high-frequency and low-frequency interference signals, as well as transient overvoltages, thereby maintaining its performance stability and reliability in complex electromagnetic environments. Furthermore, the ferrite beads are directly mounted in series, with an operating frequency between 500kHz and 1MHz.

[0053] Specifically, ferrite beads are installed in direct series within the electronic circuits of GIS high-voltage live displays. This means they are placed directly in the circuit's signal path, connected in series with the circuit's conductors. This installation method effectively filters out high-frequency components of the signal as it passes through the beads. Because the beads have a higher impedance to high-frequency signals and less impact on low-frequency or DC signals, they can effectively suppress high-frequency interference without affecting normal signal transmission. Direct series installation simplifies circuit layout, reduces complexity and potential errors during installation, and facilitates future maintenance and replacement.

[0054] The operating frequency of the ferrite beads is between 500kHz and 1MHz. This frequency range is specifically selected to address the high-frequency interference that GIS high-voltage live displays may encounter. Within this frequency range, the ferrite beads provide optimal filtering, effectively suppressing ultra-high frequency signals in conducted interference.

[0055] It should be noted that the frequency characteristics of a ferrite bead determine its impedance to signals within a specific frequency range. Ferrite beads operating between 500kHz and 1MHz are designed to handle interference within this frequency band. However, for signals below or above this frequency band, the bead's filtering effect may be reduced. Therefore, selecting the appropriate ferrite bead operating frequency is crucial to ensuring the performance of GIS high-voltage live displays in specific application environments.

[0056] By using magnetic beads within this specific operating frequency range, the GIS high-voltage live display in this embodiment can more effectively handle high-frequency interference generated by GIS operations and environmental factors, thereby ensuring stable operation and accurate display. This design improves the electromagnetic compatibility of the entire GIS system, reduces misoperation and equipment failures caused by electromagnetic interference, and enhances the safety and reliability of the power system.

[0057] Furthermore, the magnetic ring is installed in a winding manner, and the wire that introduces the high-voltage signal is wound around the magnetic ring for multiple turns.

[0058] Specifically, the magnetic ring in the GIS high-voltage live display is installed using a winding method, where the high-voltage signal conductor is wrapped around the ring multiple times. This installation method maximizes the magnetic ring's ability to suppress high-frequency interference signals in the conductor. Multiple wraps of the conductor around the magnetic ring increase the mutual inductive coupling between the ring and the conductor, thereby enhancing the ring's ability to attenuate high-frequency interference signals. The signal suppression effect of the magnetic ring increases with each wrap, thus providing more effective filtering performance.

[0059] Magnetic rings are commonly used as electromagnetic interference suppression components. They create additional impedance for high-frequency interference signals transmitted through conductors, thereby reducing their entry into electronic circuits. In GIS high-voltage live-line displays, magnetic rings are primarily used to filter out ultra-high-frequency interference signals from conducted interference. By wrapping magnetic rings around conductors, the electronic circuits within the display are protected from external high-frequency interference, ensuring proper circuit operation and accurate data transmission. The use of magnetic rings helps improve signal quality, reduce distortion and noise, and thus enhance the overall performance and reliability of GIS high-voltage live-line displays.

[0060] By adopting the winding installation method, the application of magnetic rings in GIS high-voltage live displays achieves the following effects: compared with single-turn winding or magnetic beads, multi-turn magnetic rings can provide stronger filtering effects, especially when processing high-frequency interference signals; the winding installation method can adjust the number of windings according to actual needs to adapt to different interference levels and filtering requirements; the magnetic rings have high stability and strong temperature resistance, making them suitable for long-term work in harsh environments such as GIS.

[0061] In summary, the winding and installation method of the magnetic ring is an important link in the electronic circuit design of the GIS high-voltage live display. It plays a key role in improving the anti-interference ability of the display and ensuring the stable operation of the power system.

[0062] Furthermore, the magnetic ring is a low-frequency magnetic ring with an operating frequency between 30kHz and 300kHz.

[0063] Specifically, the magnetic ring used in GIS high-voltage live displays is designed for the low-frequency range, operating between 30kHz and 300kHz. The material and structure of this magnetic ring give it high magnetic permeability within this frequency range, thereby more effectively suppressing interference signals within this frequency band.

[0064] The main function of the low-frequency magnetic ring is to filter out the low-frequency interference signal in the conducted interference. In the GIS system, in addition to ultra-high frequency interference, low-frequency interference is also a problem that needs attention because it may affect the normal operation of the display.

[0065] This embodiment selects a magnetic ring with an operating frequency between 30kHz and 300kHz, which means that the magnetic ring has the best filtering effect on signals in this specific frequency band. This targeted design helps ensure that the magnetic ring can effectively suppress the main interference frequencies in the GIS environment.

[0066] Low-frequency magnetic rings are designed with a frequency response within the 30kHz to 300kHz range in mind, ensuring stable impedance within this frequency range, effectively attenuating interference signals. The materials and coatings used for these rings typically offer excellent temperature and corrosion resistance, making them suitable for use in high-temperature, high-humidity, and dusty environments like GIS.

[0067] Wrapping a conductor multiple times around a low-frequency magnetic ring not only increases the mutual inductive coupling between the ring and the conductor, but also improves the ability to suppress low-frequency interference signals. In GIS high-voltage live displays, low-frequency magnetic rings are used in conjunction with other filtering components such as magnetic beads and inductors to form a multi-layered electromagnetic interference protection system, thereby more comprehensively protecting electronic circuits from various frequency interferences.

[0068] By adopting a low-frequency magnetic ring with an operating frequency between 30kHz and 300kHz, the GIS high-voltage live display can more effectively cope with low-frequency interference, improve its adaptability and reliability in complex electromagnetic environments, and provide important guarantees for the safe operation of the power system.

[0069] Furthermore, the inductors are installed in direct series.

[0070] Specifically, in GIS high-voltage live displays, the inductor component is installed in direct series, meaning it is directly connected to the circuit's signal path, forming a series relationship with the rest of the circuit. This installation ensures that the inductor can generate the required inductive reactance for the current passing through it, thereby fulfilling its filtering function.

[0071] The primary function of an inductor is to filter out low-frequency interference signals from conducted interference. Because the inductor's impedance to AC signals increases with frequency, it effectively blocks or attenuates low-frequency interference while allowing normal DC and low-frequency signals to pass through. Inductors also provide a degree of overcurrent protection. When current suddenly increases, the inductor generates additional inductive reactance, limiting the rate of current rise and thus protecting the circuit from damage.

[0072] The direct series installation method is simple and efficient, requiring no complex wiring or additional connectors, reducing circuit complexity and points of failure. Because the inductor is directly connected in series with the circuit, it has high stability and is not easily affected by external factors, thus ensuring the stability of the filtering effect. Inductors installed directly in series are easy to inspect and maintain and, if necessary, can be quickly replaced without affecting the rest of the circuit. The selection of the inductor takes into account its frequency response in the low-frequency range to ensure that it is effective within the operating frequency range of the GIS high-voltage live display. The design and material selection of the inductor take into account the harsh conditions of the GIS environment, such as high temperature and high humidity, to ensure that its performance remains unchanged during long-term use.

[0073] By adopting the direct series installation method, the inductor plays its due filtering and protection role in the GIS high-voltage live display, which helps to improve the display's anti-interference ability and working reliability in an electromagnetic interference environment, thereby ensuring the safe and stable operation of the power system.

[0074] The above disclosure is merely a preferred embodiment of the present invention and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A high voltage live indicator for GIS, characterized in that: include: The shell is made of aluminum-zinc sheet material to attenuate external magnetic field interference; An inner shell made of aluminum alloy plate, located inside the outer shell, for suppressing electric field interference; an electronic circuit disposed in the inner shell; as well as Copper foil tape is used to seal the joints between the outer shell and the inner shell to prevent interference signals from entering the interior through the gap; The electronic circuit includes a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit and a charged display circuit which are electrically connected in sequence; The magnetic beads are used to filter out ultra-high frequency interference signals in conducted interference; The magnetic ring is used to filter out ultra-high frequency interference signals in the conducted interference; The inductor is used to filter out low-frequency interference signals in the conducted interference; The overvoltage protection circuit is used to suppress transient overvoltages introduced through the wires; The live display circuit is used to display the live status of electrical equipment inside the GIS, providing intuitive safety instructions.

2. The high-voltage live indicator for GIS according to claim 1, further characterized in that: The magnetic beads are installed in direct series, and the operating frequency of the magnetic beads is between 500kHz and 1MHz.

3. The high-voltage live indicator for GIS according to claim 1 is further characterized in that: The magnetic ring is installed in a winding manner, and the wire for introducing the high-voltage signal is wound around the magnetic ring for multiple turns.

4. The high-voltage live indicator for GIS according to claim 1 is further characterized in that: The magnetic ring is a low-frequency magnetic ring with an operating frequency between 30kHz and 300kHz.

5. The high-voltage live indicator for GIS according to claim 1 is further characterized in that: The inductors are installed in direct series.

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