High-voltage live display for GIS (Gas Insulated Switchgear)

Abstract

The invention provides a high-voltage live display for a GIS, and the display comprises a housing which is made of an aluminum-coated zinc plate and is used for attenuating the interference of an external magnetic field; the inner shell is made of an aluminum alloy plate, is positioned in the outer shell and is used for inhibiting electric field interference; the electronic circuit is arranged in the inner shell; the copper foil adhesive tape is used for sealing a seam between the outer shell and the inner shell and preventing interference signals from entering the interior through the seam; wherein the electronic circuit comprises a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit and a live display circuit; the magnetic beads are used for filtering ultrahigh-frequency interference signals in conducted interference; the magnetic ring is used for filtering ultrahigh frequency interference signals in conducted interference; the inductor is used for filtering low-frequency interference signals in conducted interference; the overvoltage protection circuit is used for suppressing transient overvoltage which is connected in series through a wire. And the live display circuit is used for displaying the live state of electrical equipment in the GIS and providing visual safety indication. The high-voltage live display can effectively shield conducted radiation and space radiation at the same time.

Description

Technical Field

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

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

[0003] Since the overall structure of GIS is closed, it is impossible to visually judge the live status of the internal electrical equipment. The live operation of GIS is extremely dangerous, posing a great threat to the life safety of the staff and easily causing safety accidents. The live display widely used in the power system at present is mainly to extract a certain voltage from the high-voltage live circuit as the power supply for display and locking by pumping the capacitor core rod, which is used to reflect the live status of the device setting and can force the switch to lock. The high-voltage live display plays a vital role in reflecting whether the electrical equipment has an operating voltage and forcing the electrical locking function.

[0004] GIS usually uses a high voltage level (110kV and above) and is in a strong electromagnetic interference environment. When the circuit breaker is activated, currents of tens to hundreds of kA appear, causing extremely strong electromagnetic interference inside and around the GIS closed structure, far exceeding the values ​​specified by current national standards. Conventional high-voltage live displays are prone to display abnormalities and frequent damage in such a strong electromagnetic environment, leading to misjudgment by operation and maintenance personnel, resulting in serious safety hazards and even major safety accidents such as personal injury or death.

[0005] There are two types of strong electromagnetic interference in GIS: conducted radiation and space radiation. Since the high-voltage live display of GIS is directly connected to the primary circuit of GIS through a high-voltage capacitive sensor, there is a direct conduction path, which causes serious conducted radiation. In addition, the high-voltage live display is installed in the GIS control terminal box, which is very close to the GIS body. When the switch inside the GIS is activated, it will generate extremely strong space radiation, which can easily affect the operation of the high-voltage live display.

[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, while achieving 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 to 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 display 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, the inner shell is located inside the outer shell and is used to suppress 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 comprises 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 the 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 overvoltage injected through the wire;

[0018] The live display circuit is used to display the live status of electrical equipment inside the GIS and provide 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 for introducing the high-voltage signal is wound around the magnetic ring for multiple turns.

[0021] Furthermore, the magnetic ring is a low-frequency magnetic ring, and the operating frequency is 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 to the primary circuit of the GIS through a high-voltage capacitor sensor, there is a direct conduction path, which is easily affected by conducted radiation. Therefore, the embodiment of the present invention effectively filters out conducted interference through components such as magnetic beads, magnetic rings, and inductors in the electronic circuit.

[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 spatial radiation generated when the internal switch of the GIS is actuated. Therefore, the electromagnetic shielding design of the embodiment of the present invention has a good effect of attenuating the magnetic field. The aluminum alloy plate material has good conductivity and can suppress the electric field interference caused by the change of the magnetic field. The gap between the outer shell and the inner shell is sealed with a copper foil tape with good ductility to prevent the interference with shorter wavelengths from entering the interior of the GIS high-voltage live display through the air, effectively filtering out the spatial radiation interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the present invention.

[0027] Figure 1 The present invention is a schematic structural diagram of a high-voltage live display for GIS in one embodiment of the present invention.

[0028] Markings in the figure: 1-outer shell, 2-inner shell, 3-copper foil tape, 4-magnetic bead, 5-magnetic ring, 6-inductor, 7-overvoltage protection circuit, 8-powered display circuit. DETAILED DESCRIPTION

[0029] The detailed description of the drawings is intended as an illustration of the current embodiment 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 accomplished by different embodiments intended to be included in the spirit and scope of the present application.

[0030] See also Figure 1 The embodiment of the present invention provides a high voltage live display for GIS, including:

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

[0032] An inner shell made of aluminum alloy plate, the inner shell is located inside the outer shell and is used to suppress electric field interference;

[0033] An electronic circuit disposed in the inner housing; and

[0034] 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;

[0035] Wherein, the electronic circuit comprises a magnetic bead, a magnetic ring, an inductor, an overvoltage protection circuit and a charged display circuit which are electrically connected in sequence;

[0036] The magnetic beads are used to filter out ultra-high frequency interference signals in the conducted interference;

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

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

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

[0040] The live display circuit is used to display the live status of electrical equipment inside the GIS and provide intuitive safety instructions.

[0041] Specifically, the GIS high-voltage bus carries high voltage, and three-phase high-voltage sensors (also called voltage transformers or PTs) are used to convert the high-voltage signals on the high-voltage bus into safe low-voltage electrical signals. These sensors have high precision and reliability and can adapt to the harsh environment inside the GIS. The converted low-voltage electrical signals are connected to the terminals of the GIS-specific high-voltage live display through special cables. 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 ferrite beads, which serve as the first filtering element of the circuit to filter out ultra-high frequency interference signals in the conducted interference.

[0042] In the GIS (gas-insulated fully enclosed switchgear) system, the high-voltage live display plays a vital role. It provides key live status indications for operation and maintenance personnel to ensure 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 interferences have high frequencies and short wavelengths, which pose a challenge to the normal operation of the display. In order to meet these challenges, the GIS high-voltage live display of this embodiment has the following special treatments on the shell structure:

[0043] Alu-zinc plate is a material with excellent electromagnetic shielding performance. It can effectively attenuate the magnetic field strength in high-frequency electromagnetic fields. Compared with traditional stainless steel, alu-zinc plate has a better magnetic field attenuation effect. Although stainless steel is strong, its shielding effect on magnetic fields is not as good as that of alu-zinc plate. Therefore, in an environment with strong electromagnetic interference, alu-zinc plate is a more suitable choice. The alu-zinc plate shell forms a protective layer, which reduces the impact of external electromagnetic fields on internal electronic circuits.

[0044] The aluminum alloy plate has excellent electrical conductivity and can form an equipotential surface, which effectively suppresses 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, and reduce the impact of electric field interference on electronic circuits.

[0045] At the joints between the outer shell and the inner shell, there are inevitably some gaps due to manufacturing and assembly reasons. These gaps may become channels for high-frequency electromagnetic waves to enter the display. Sealing these gaps with copper foil tape with good ductility can effectively block the propagation path of high-frequency electromagnetic waves. Copper foil tape not only has good conductivity, but also can fit the gaps tightly to ensure the integrity of electromagnetic shielding. This sealing measure is particularly important for interference with shorter wavelengths, because short-wavelength electromagnetic waves are more likely to enter the inside of the device through tiny gaps.

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

[0047] In the design of GIS high-voltage live display, conducted interference is an issue that requires special attention, because the display is connected to the high-voltage capacitive sensor through a wire and is directly exposed to conducted interference. In order to ensure the accuracy and stability of the display, a variety of components are used in the electronic circuit to filter out interference signals in different frequency ranges. The following is a detailed description of the functions of these components:

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

[0049] Magnetic rings are similar to magnetic beads and are also components used to filter out high-frequency interference. Magnetic rings are usually used to wind wires, forming a low-impedance path specifically for high-frequency signals. In GIS high-voltage live displays, magnetic rings are used to further filter out ultra-high frequency signals in conducted interference. By winding the wire around the magnetic ring multiple times, its filtering effect can be enhanced. The selection of magnetic rings is usually based on their operating frequency range. The operating frequency of the magnetic ring mentioned in the present invention is between 30kHz and 300kHz, which just covers the high-frequency interference that may be generated during GIS operation.

[0050] Inductors are components that can suppress low-frequency interference signals. Through their inductance characteristics, they generate impedance to low-frequency signals, thereby reducing the impact of these signals on electronic circuits. In GIS high-voltage live displays, inductors are used to filter out low-frequency components in conducted interference, which may come from the fundamental frequency and harmonics of the power system. Inductors are usually installed in direct series to ensure that low-frequency interference signals are effectively suppressed before entering the electronic circuit.

[0051] Overvoltage protection circuit is an indispensable part of electronic circuit. It is used to suppress transient overvoltage through wires and protect electronic components from damage. In GIS high voltage live display, overvoltage protection circuit can respond quickly and limit the amplitude of overvoltage to ensure that electronic circuits are not damaged when voltage is abnormal.

[0052] Through the comprehensive application of these electronic circuit elements, the GIS high-voltage live display can effectively filter out conducted interference, including ultra-high frequency and low frequency interference signals, as well as transient overvoltage, thereby maintaining the stability and reliability of its performance in a complex electromagnetic environment. Furthermore, the magnetic beads are directly installed in series, and the operating frequency of the magnetic beads is between 500kHz and 1MHz.

[0053] Specifically, the magnetic beads are installed in direct series in the electronic circuit of the GIS high-voltage live display, which means that the magnetic beads are placed directly on the signal path of the circuit and connected in series with the wires of the circuit. This installation method allows the high-frequency components of the signal to be effectively filtered out when passing through the magnetic beads. Since the magnetic beads have a higher impedance to high-frequency signals and have less impact on their low-frequency or DC signals, they can specifically suppress high-frequency interference without affecting normal signal transmission. The direct series installation method simplifies the circuit layout, reduces the complexity and possible errors during the installation process, and is also conducive to future maintenance and replacement.

[0054] The working frequency of the magnetic beads is between 500kHz and 1MHz. This frequency range is specially selected for the high-frequency interference that may be encountered by GIS high-voltage live displays. In this frequency range, the magnetic beads can provide the best filtering effect and effectively suppress the ultra-high frequency signals in the conducted interference.

[0055] It should be noted that the frequency characteristics of the magnetic bead determine its impedance to the signal within a specific frequency range. For magnetic beads operating at 500kHz to 1MHz, it is designed to handle interference within this frequency band, while for signals below or above this frequency band, the filtering effect of the magnetic beads may be weakened. Therefore, choosing the appropriate magnetic bead operating frequency is crucial to ensuring the performance of the GIS high-voltage live display in a specific application environment.

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

[0057] Furthermore, 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.

[0058] Specifically, the installation of the magnetic ring in the GIS high-voltage live display adopts a winding method, that is, the wire of the high-voltage signal is wound around the magnetic ring in multiple turns. This installation method can maximize the suppression effect of the magnetic ring on the high-frequency interference signal in the wire. Winding the wire around the magnetic ring multiple times can increase the mutual inductance coupling between the magnetic ring and the wire, thereby enhancing the attenuation effect of the magnetic ring on the high-frequency interference signal. With each winding, the suppression effect of the magnetic ring on the signal will be enhanced, so multiple windings can provide more effective filtering performance.

[0059] Magnetic ring is a commonly used electromagnetic interference suppression component, which can generate additional impedance to high-frequency interference signals transmitted through wires, thereby reducing these signals from entering electronic circuits. In GIS high-voltage live displays, magnetic rings are mainly used to filter out ultra-high frequency interference signals in conducted interference. By wrapping magnetic rings around the wires, the electronic circuits inside the display can be protected from external high-frequency interference, ensuring the normal operation of the circuit and accurate transmission of data. The use of magnetic rings helps to improve the quality of signals, reduce signal distortion and noise, and thus improve the overall performance and reliability of GIS high-voltage live 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 winding 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 ring has high stability and strong temperature resistance, and is 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, and the operating frequency is between 30kHz and 300kHz.

[0063] Specifically, the magnetic ring used in GIS high-voltage live displays is designed for the low-frequency range, and its operating frequency is between 30kHz and 300kHz. The material and structure of this magnetic ring give it a higher magnetic permeability within this frequency range, which can more effectively suppress 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 the ultra-high frequency interference, the low-frequency interference is also a problem that needs attention, because they 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 the signal in this specific frequency band. This targeted design helps to ensure that the magnetic ring can effectively suppress the main interference frequencies in the GIS environment.

[0066] The low-frequency magnetic ring is designed with its frequency response in the range of 30kHz to 300kHz in mind to ensure stable impedance in this frequency range, thereby effectively attenuating interference signals. The material and coating of the magnetic ring usually have good temperature resistance and corrosion resistance, and are suitable for use in high temperature, high humidity, and dusty environments such as GIS.

[0067] Wrapping the wire around the low-frequency magnetic ring for multiple turns not only increases the mutual inductance coupling between the magnetic ring and the wire, 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-level electromagnetic interference protection system, thereby more comprehensively protecting electronic circuits from various frequency interferences.

[0068] By adopting low-frequency magnetic rings with operating frequencies 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 the GIS high-voltage live display, the inductor element is installed in direct series, which means that the inductor is directly connected to the signal path of the circuit and forms a series relationship with other parts of the circuit. This installation method ensures that the inductor can produce the required inductive reactance to the current passing through it, thereby playing its filtering role.

[0071] The main function of the inductor is to filter out low-frequency interference signals in the conducted interference. Since the impedance of the inductor to the AC signal increases with the increase of frequency, it can effectively block or attenuate the interference in the low-frequency range, while allowing the normal DC and low-frequency signals to pass. The inductor can also provide a certain over-current protection, because when the current suddenly increases, the inductor will generate additional inductive reactance to limit the rate of increase of the current, thereby protecting the circuit from damage.

[0072] The direct series installation method is simple and efficient, without the need for complex wiring or additional connectors, which reduces the complexity of the circuit and reduces the number of failure points. Since the inductor is directly connected in series in the circuit, it has high stability and is not easily affected by external factors, ensuring the stability of the filtering effect. Inductors installed directly in series are easy to inspect and maintain, and can be quickly replaced if necessary without affecting the rest of the entire 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 such as high temperature and high humidity in the GIS environment 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 only the preferred embodiment of the present invention, which 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, the inner shell is located inside the outer shell and is used to suppress 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; Wherein, the electronic circuit comprises 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 the 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 overvoltage injected through the wire; The live display circuit is used to display the live status of electrical equipment inside the GIS and provide intuitive safety instructions.

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

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

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

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