Wide-band GIS voltage transformer

Abstract

The present application relates to a kind of wideband GIS voltage transformer, including metal shell, high voltage conductor, capacitive voltage division mutual inductance module, suspended light force electric field sensing module and signal processing module.Capacitive voltage division mutual inductance module is formed coupling capacitor by electrode spaced apart with high voltage conductor middle section, and output first detection signal;High voltage conductor and metal shell form space electric field, suspended light force electric field sensing module according to the movement response of charged suspended microparticle in space electric field output second detection signal.Signal processing module determines the voltage component of different frequency range in primary voltage according to first detection signal and second detection signal respectively, to realize the wideband measurement of power frequency voltage, high frequency voltage.

Description

Technical Field

[0001] This invention belongs to the field of voltage transformer technology, and specifically relates to a wideband GIS voltage transformer. Background Technology

[0002] Voltage transformers are crucial measuring devices in power systems used to obtain voltage information from primary equipment. Their outputs can be used by metering, monitoring, control, and relay protection systems. For gas-insulated metal-enclosed switchgear (GIS), voltage transformers not only need to meet insulation requirements under high-voltage conditions but also need to adapt to the compact structure, sealed gas chambers, complex electromagnetic environment, and online digital measurement requirements of GIS equipment.

[0003] Existing voltage transformers mainly include electromagnetic voltage transformers and capacitive voltage transformers. Electromagnetic voltage transformers typically utilize the electromagnetic induction relationship between the primary winding, secondary winding, and core to achieve voltage transformation. As the primary voltage level increases, the winding insulation distance, core size, and overall weight increase accordingly, making manufacturing and insulation coordination more difficult. Simultaneously, the core may be affected by factors such as magnetic saturation, remanence, and ferroresonance, limiting its response capability in fast transient or wide dynamic range measurement scenarios.

[0004] Capacitive voltage transformers typically use a capacitor divider unit composed of a high-voltage capacitor and a voltage divider capacitor, and an electromagnetic unit composed of a compensating reactor, a medium-voltage transformer, and damping devices to convert the primary high voltage into a voltage signal usable by the secondary system. This type of transformer contains numerous capacitors, reactors, transformers, and damping components, resulting in a long measurement chain and a complex overall structure and insulation interfaces. The transmission network formed by the capacitors and inductors can also attenuate, oscillate, or delay transient voltages, affecting the accurate reflection of rapid voltage changes.

[0005] Therefore, existing technologies urgently need to overcome the aforementioned defects in existing transformer types and develop voltage transformers that do not excessively increase in size under high primary voltage and have sensitive transient response capabilities. Summary of the Invention

[0006] One of the objectives of this invention is to solve at least one or more of the aforementioned problems existing in the prior art. In other words, one of the objectives of this invention is to provide a wideband GIS voltage transformer that meets the aforementioned requirements.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a wideband GIS voltage transformer, comprising: Metal casing, electrically connected to a reference potential; An insulating support component is airtightly connected to a metal shell, and the insulating support component and the metal shell together form an insulating gas chamber filled with insulating gas. The high-voltage conductor passes through the insulating support member. Its first end is electrically connected to the primary equipment outside the metal shell, and its second end is located in the insulating air chamber, forming a spatial electric field between it and the metal shell that varies with the primary voltage carried by the high-voltage conductor. The capacitor voltage divider mutual inductor module includes electrodes, voltage divider capacitors, and an electronic acquisition unit; The electrode is placed in an insulating gas chamber, spaced apart from the high-voltage conductor in the middle section between the first and second ends, and forms a coupling capacitor with the high-voltage conductor; the two ends of the voltage divider capacitor are electrically connected to the electrode and the metal shell respectively; the electronic acquisition unit acquires the voltage divider voltage across the voltage divider capacitor and outputs a first detection signal characterizing the primary voltage; The suspended photoelectric field sensing module is set apart from the high-voltage conductor in an insulating air chamber. It outputs a second detection signal characterizing the primary voltage based on the motion response of charged suspended particles under the action of a spatial electric field. The signal processing module is connected to the electronic acquisition unit and the levitation photoelectric field sensing module. Based on the first detection signal and the second detection signal, it determines the voltage components in the primary voltage whose frequencies are in the first frequency range and the second frequency range, respectively; the second frequency range is higher than the first frequency range.

[0008] In a preferred embodiment, the electrode is a cylindrical electrode disposed around the middle section of the high-voltage conductor, the cylindrical electrode having an axial opening toward a second end of the high-voltage conductor, the second end extending from the axial opening and located outside the axial coverage area of ​​the cylindrical electrode.

[0009] In a preferred embodiment, the second end of the high-voltage conductor is formed into a spherical end.

[0010] In one preferred embodiment, the levitation photoelectric field sensing module includes an insulating sensor housing, an optical constraint unit, charged suspended particles, and an optical detection unit. A vacuum environment is formed inside the insulating sensor housing. The optical constraint unit is used to constrain the charged suspended particles to a predetermined position within the insulating sensor housing. The optical detection unit is used to detect the motion response of the charged suspended particles under the action of the spatial electric field and output a second detection signal.

[0011] As a further preferred embodiment, the optical detection unit is used to receive the scattered light formed by charged suspended particles under laser irradiation, and generate a second detection signal according to the change of the scattered light.

[0012] As a further preferred embodiment, the change in scattered light includes at least one of a change in spot position and a change in phase, and the second detection signal is used to characterize the displacement response of the charged suspended particles.

[0013] In one preferred embodiment, the suspended photoelectric field sensing module is disposed in the insulating chamber on the side opposite to the insulating support.

[0014] In a preferred embodiment, when the signal processing module determines the voltage component in the primary voltage that is higher than the first frequency range based on the second detection signal, it determines the displacement response of the charged suspended particles based on the second detection signal, determines the electric force on the charged suspended particles based on the displacement response and the predetermined relationship between the particle mechanical response, determines the electric field parameters at a predetermined position based on the electric field force and the charge of the charged suspended particles, and determines the primary voltage based on the correspondence between the electric field parameters and the primary voltage.

[0015] As a further preferred embodiment, the particle mechanical response relationship is calculated from the mass of the charged suspended particle, the resonant frequency of the charged suspended particle, and the damping coefficient.

[0016] In a preferred embodiment, the insulating gas is sulfur hexafluoride gas.

[0017] Compared with the prior art, the wideband GIS voltage transformer provided by the present invention has the following advantages: In this invention, the levitation optical electric field sensing module can sense the spatial electric field corresponding to the primary voltage without direct electrical connection to the high-voltage conductor. Under the premise of electrical isolation between high and low potentials, it uses a non-contact optical method to read the electric field effect, thus realizing the sensing of the primary voltage. At the same time, this module does not rely on iron core magnetic coupling or capacitive voltage division, which can reduce the attenuation and delay of high-frequency transient components in traditional electromagnetic or capacitive current transformer transmission networks.

[0018] Furthermore, this invention also incorporates a capacitive voltage divider mutual inductance module within the same GIS insulating chamber, using two modules and two different detection principles to obtain a first detection signal and a second detection signal, respectively. The signal processing module determines the voltage component within a first frequency range in the primary voltage based on the first detection signal, and determines the voltage component within a second frequency range based on the second detection signal. The capacitive voltage divider detection channel achieves accurate measurement of power frequency and low-frequency voltage components, while the suspended optical electric field detection channel achieves measurement of high-frequency and transient voltage components. This further addresses the relative weakness of the suspended optical electric field detection method in the low-frequency range, allowing the two detection channels to operate within their respective frequency ranges where measurement is advantageous, thus accommodating both power frequency and high-frequency voltage measurements. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a broadband GIS voltage transformer according to an embodiment of the present invention.

[0020] Reference numerals: Metal casing-1, Insulating support-2, First end-301, Middle section-302, Second end-303, Electrode-401, Voltage divider capacitor-402, Electronic acquisition unit-403, Suspended photoelectric field sensing module-5, Optical cable-6, Signal processing module-7. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0022] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the described elements without departing from the scope of the invention. Various processes or components may be appropriately omitted, substituted, or added to the various examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into other examples.

[0023] An embodiment of the present invention provides a wideband GIS voltage transformer, the structural schematic diagram of which is shown below. Figure 1 As shown, it includes a metal shell 1, an insulating support 2, a high-voltage conductor, a capacitor voltage divider mutual inductance module, a suspended optical force electric field sensing module 5, an optical cable 6, and a signal processing module 7.

[0024] The metal housing 1 is electrically connected to the reference potential. The insulating support 2 is hermetically connected to the metal housing 1 and together with the metal housing 1, forms an insulating chamber filled with insulating gas. The high-voltage conductor is supported by the insulating support 2 and passes through the insulating support 2. Its first end 301 is located outside the metal housing 1 and is used for electrical connection with the primary equipment. The second end 303 is located inside the insulating chamber. The middle section 302 between the first end 301 and the second end 303 is opposite to the electrode 401 in the capacitive voltage divider mutual inductance module. The suspended optical force electric field sensing module 5 is fixed inside the insulating chamber and spaced apart from the high-voltage conductor. The signal processing module 7 is electrically connected to the electronic acquisition unit 403 in the coaxial capacitive voltage divider mutual inductance module and is connected to the suspended optical force electric field sensing module 5 inside the insulating chamber through an optical cable 6 that passes through the metal housing 1.

[0025] Among them, the metal shell 1 is a conductive shell surrounding the high-voltage conductor and the suspended photoelectric field sensing module 5. On the one hand, it forms the boundary of the insulating air chamber, and on the other hand, it serves as a reference potential electrode opposite to the high-voltage conductor.

[0026] In some implementations, the metal casing 1 is grounded, so the reference potential is the ground potential. When the primary voltage of the primary equipment is applied to the high-voltage conductor, the high-voltage conductor is at a relatively high potential, and the metal casing 1 is at the reference potential. At this time, the potential difference between the two establishes a spatial electric field in the insulating chamber.

[0027] The insulating support 2 participates in forming the airtight boundary of the insulating chamber and is used to support the high-voltage conductor while isolating the high-voltage conductor from the potential of the metal shell 1.

[0028] In some embodiments, the insulating support 2 is an insulator with a basin-shaped, inwardly protruding design. Specifically, the basin-shaped insulator is located on one side of the metal housing 1, with its outer periphery airtightly connected to the metal housing 1. The high-voltage conductor passes through the central area of ​​the basin-shaped insulator and is supported by it. In this case, the insulating support 2 simultaneously serves as an insulating seal and a mechanical support, structurally fixing the metal housing 1 and the high-voltage conductor while maintaining the airtightness of the insulating chamber.

[0029] The insulating chamber is an insulating space located inside the metal shell 1, enclosed by a metal shell 1 and an insulating support 2 that is airtightly connected to it. An insulating gas fills this insulating chamber and serves as the insulating medium between the high-voltage conductor and the metal shell 1. In some more specific embodiments, the insulating gas is sulfur hexafluoride gas.

[0030] The high-voltage conductor is fixedly supported by an insulating support 2, including a first end 301 located outside the metal shell 1, a second end 303 located inside the insulating chamber, and a middle section 302 located between the first end 301 and the second end 303 and inside the insulating chamber.

[0031] The capacitive voltage divider module includes electrodes 401, a voltage divider capacitor 402, and an electronic acquisition unit 403. Electrode 401 is disposed within an insulating chamber and spaced apart from the middle section 302 of the high-voltage conductor, forming the two poles of a coupling capacitor. The first terminal of the voltage divider capacitor 402 is electrically connected to electrode 401, and the second terminal is electrically connected to the metal casing 1, causing the primary voltage carried by the high-voltage conductor to form a voltage divider across the voltage divider capacitor 402. The electronic acquisition unit 403 is connected across the voltage divider capacitor 402, samples the voltage divider, and outputs a first detection signal characterizing the primary voltage.

[0032] The first end 301 of the high-voltage conductor is electrically connected to the primary equipment to receive the primary voltage being measured; the middle section 302 and the electrode 401 of the capacitor voltage divider mutual inductor module respectively form the two poles of the coupling capacitor; the second end 303 in the insulating gas chamber acts as a high-potential electrode and generates an electric field with the metal shell 1 at the reference potential.

[0033] The above structure forms two voltage response relationships through the coupling of the middle section 302 with the electrode 401 and the coupling of the second end 303 with the metal shell 1: When the primary voltage changes, the voltage change of the primary device is converted into a voltage divider change that can be collected on the voltage divider capacitor 402 through the coupling capacitor formed by the middle section 302 and the electrode 401; in addition, the potential difference between the high voltage conductor and the metal shell 1 changes accordingly, and the spatial electric field in the insulating gas chamber also changes accordingly, thereby converting the voltage change of the primary device into a field change that can act on the charged suspended particles in the insulating gas chamber.

[0034] In some embodiments, electrode 401 is a cylindrical electrode. The cylindrical electrode is disposed around the middle section 302 of the high-voltage conductor, with the middle section 302 located inside the cylindrical electrode and the two maintained at a radial distance. When the cylindrical electrode and the middle section 302 of the high-voltage conductor are coaxially disposed, an annular insulating gap filled with insulating gas is formed between the inner circumferential surface of the cylindrical electrode and the outer circumferential surface of the middle section 302 of the high-voltage conductor, and the electric field is distributed in a coaxial cylindrical shape within the annular insulating gap.

[0035] For the aforementioned coaxial cylindrical coupling capacitor, its capacitance value Determined according to the following formula: .

[0036] in, It is the vacuum permittivity; is the relative permittivity of the dielectric. The outer radius of the high-voltage conductor; The inner radius of the cylindrical electrode; is the length of the cylindrical electrode.

[0037] The capacitance value of voltage divider capacitor 402 It can be determined using the following formula: .

[0038] in, is the relative permittivity of the intermediate insulating medium; The thickness is the outer cylinder.

[0039] When a voltage is applied to the high-voltage conductor At that time, the formula derived from circuit principles is as follows: .

[0040] The voltage across the voltage divider capacitor 402 can be obtained. for: .

[0041] The voltage ratio can be calculated as follows: .

[0042] The cylindrical electrode has an axial opening toward the second end 303 of the high-voltage conductor, from which the second end 303 extends. Viewed radially along the high-voltage conductor, the cylindrical electrode covers only the middle section 302 of the high-voltage conductor, with its side toward the second end 303 terminating before the second end 303, thus placing the second end 303 outside the axial coverage area of ​​the cylindrical electrode.

[0043] It is understood that the aforementioned axial coverage area is the range occupied by the cylindrical electrode between its two ends in the axial direction of the high-voltage conductor.

[0044] The aforementioned axial relationship forms two action regions arranged along the axial direction of the high-voltage conductor: within the axial coverage area of ​​the cylindrical electrode, a capacitive coupling region is formed between the middle section 302 of the high-voltage conductor and the cylindrical electrode; outside the axial coverage area of ​​the cylindrical electrode facing the second end 303, a spatial electric field region is formed between the second end 303 of the high-voltage conductor and the metal shell 1. The suspended photoelectric field sensing module 5 is arranged on the side opposite to the insulating support 2 and corresponds to the spatial electric field detection region where the second end 303 is located. Since the cylindrical electrode does not continue to surround the second end 303, this structure helps to reduce the shielding and disturbance of the spatial electric field near the second end 303 by the cylindrical electrode, thereby reducing interference to the second detection signal.

[0045] In some embodiments, the second end 303 forms a spherical end that protrudes toward the center of the gas chamber. The rounded and continuous surface profile of this spherical end can mitigate the tendency of electric field lines to concentrate at the conductor end compared to sharp ends or abrupt changes in profile, thereby reducing the local electric field concentration at the high-voltage conductor end and preventing partial discharge from occurring in the GIS device.

[0046] The levitation photoelectric field sensing module 5 is used to convert the spatial electric field change at its location into a second detection signal. The module is fixed in an insulating air chamber and spaced apart from the high-voltage conductor to ensure that the sensing module does not directly receive the potential of the high-voltage conductor, but indirectly senses the potential change on the high-voltage conductor through the spatial electric field.

[0047] In some embodiments, the insulating support 2 is located on one side of the insulating air chamber, and the suspended photoelectric field sensing module 5 is located on the side of the insulating air chamber opposite to the insulating support 2 and is installed on the inner wall of the metal housing 1 in a low potential region.

[0048] This opposite-side arrangement allows the suspended photoelectric field sensing module 5 to be in the spatial electric field formed by the high-voltage conductor and the metal shell 1 while maintaining a distance from the high-voltage conductor, and to be in a more sensitive sensing position.

[0049] The levitation optical electric field sensing module 5 is fixed in an insulating air chamber, and the optical cable 6 passes through the metal shell 1 and connects to the outside. When the primary voltage carried by the high-voltage conductor changes, the potential difference between the high-voltage conductor and the metal shell 1 changes, and the electric field parameters at the fixed position of the levitation optical electric field sensing module 5 change accordingly. Thus, the pre-determined correspondence between the electric field parameters and the primary voltage can map the local field quantity at the fixed position back to the primary voltage.

[0050] As a feasible example, the levitation photoelectric field sensing module 5 includes an insulating sensor housing, an optical constraint unit, charged levitation particles, and an optical detection unit. The insulating sensor housing surrounds the working space of the charged levitation particles, forming a vacuum environment inside and an insulating gas chamber outside. This vacuum environment provides the working space for the optical constraint and force-induced motion of the particles, enabling the spatial electric field to induce particle motion read by the optical detection unit.

[0051] The optical constraint unit is used to constrain charged suspended particles to a predetermined position within the insulating sensor housing. It captures charged suspended particles through the action of an optical potential trap and forms an optical constraint, so that the particles remain at the predetermined position when the electric field to be measured does not change.

[0052] The charged suspended particles are the mechanical conversion components between the spatial electric field and optical readout. Specifically, the charged suspended particles have a charge. When they are located in the spatial electric field formed by the high-voltage conductor and the metal shell 1, the spatial electric field exerts a Coulomb force on the particles. A voltage change will cause a change in the spatial electric field at the location of the charged suspended particles, which in turn causes a change in the electric force on the particles. At this time, the particles will produce a displacement corresponding to the voltage change near the predetermined position formed by the optical constraint.

[0053] The optical detection unit is used to receive the scattered light generated by charged suspended particles under laser irradiation and to generate a second detection signal based on the changes in the scattered light. Specifically, the laser irradiating the particles interacts with the particles to form scattered light. Changes in the spatial position of the particles modulate the light field distribution of the scattered light, and the optical detection unit can thus receive the changes in the scattered light along its propagation path.

[0054] As an example, this change can include changes in the position of the light spot and changes in the phase. The change in the position of the light spot reflects the change in the spatial distribution of the scattered light as the position of the particles changes, and the change in the phase reflects the change in the phase state of the scattered light as the particles move.

[0055] One end of the optical cable 6 is connected to the suspended photoelectric field sensing module 5 located in the insulating air chamber, and the other end passes through the boundary of the metal shell 1 and is connected to the signal processing module 7 located outside the metal shell 1, so that the second detection signal can be transmitted across the metal shell 1 to the outside of the shell and the airtight state of the insulating air chamber is maintained.

[0056] The signal processing module 7 is located outside the metal housing 1, connected to the electronic acquisition unit via a cable, and connected to the suspended photoelectric field sensing module 5 via an optical cable 6.

[0057] The signal processing module 7 is used to determine the voltage component in the primary voltage whose frequency is in a first frequency range based on the first detection signal, and to determine the voltage component in the primary voltage whose frequency is in a second frequency range based on the second detection signal.

[0058] The capacitive voltage divider mutual inductance module exhibits a relatively stable voltage division relationship and high measurement accuracy within the first frequency range, including the power frequency. However, its ability to identify higher harmonic voltage components and high-frequency transient voltage components is relatively limited. The levitation optical-electric field sensing module 5 utilizes charged suspended particles to respond to changes in the spatial electric field, exhibiting a fast high-frequency and transient response. However, its measurement sensitivity and accuracy within the power frequency range are relatively lower than those of the capacitive voltage divider detection channel.

[0059] Understandably, the second frequency range is higher than the first frequency range, so as to be compatible with the advantageous operating frequency bands of the levitation optical force electric field sensing module 5 and the capacitor voltage divider mutual inductance module, respectively.

[0060] Therefore, the signal processing module 7 determines the voltage component in the primary voltage that is within the first frequency range based on the first detection signal, and determines the voltage component in the second frequency range based on the second detection signal, so that the two detection channels operate in their respective frequency ranges where they have measurement advantages, thereby achieving wide-band accurate detection of both the power frequency voltage component and the high frequency voltage component in the primary voltage.

[0061] When determining the voltage component in the primary voltage whose frequency falls within the second frequency range based on the second detection signal, the signal processing module 7 uses the following method: The displacement response of the charged suspended particles is determined based on the second detection signal. The electric force on the charged suspended particles is determined based on the displacement response and the predetermined relationship between the particle mechanical response and the displacement response. The electric field parameters at the predetermined position are determined based on the electric field force and the charge of the charged suspended particles. The primary voltage is determined based on the correspondence between the electric field parameters and the primary voltage.

[0062] Specifically, the signal processing module 7 takes the second detection signal as input, first determines the displacement response of the charged suspended particles by the change in the position or phase of the scattered light spot, and then determines the electric force on the particles based on the displacement response and the predetermined relationship between the particle mechanical response and the electric field. Subsequently, it determines the electric field parameters at the suspension position based on the electric field force and the charge of the particles. Under the conditions that the reference potential of the metal shell 1 and the position of the high voltage conductor-metal shell 1-suspended photoelectric field sensing module 5 are determined, the local electric field parameters will change accordingly with the potential difference caused by the primary voltage, so that the signal processing module 7 can determine the primary voltage according to the predetermined correspondence.

[0063] As a feasible example, signal processing module 7 can determine the applied electric field strength at the location of the charged suspended particles based on the following relationship: ; .

[0064] in, Indicates the applied electric field strength. This represents the electric force experienced by the particle. This represents the total charge of the particles. This represents the number of charges on a charged particle. Represents the elementary charge. Indicates the displacement of the particle. Represents the transfer function. Indicates the mass of the particles. It represents the external driving frequency (the frequency of the change in the applied electric field). This represents the resonant frequency of the particle, i.e., the natural vibration frequency of the optical potential trap. This represents the damping coefficient.

[0065] Based on the strength of the applied electric field, combined with the geometric structure and positional relationship of the high-voltage conductor, the metal shell 1, and the suspended photoelectric field sensing module 5, the change in potential difference can be calculated, thereby obtaining the primary voltage change applied to the high-voltage conductor by the primary equipment, and realizing the voltage mutual inductance function.

[0066] The aforementioned device utilizes the existing electrode relationship between the high-voltage conductor and the metal casing 1 to generate the electric field in the space to be measured. The suspended optical electric field sensing module 5 is not directly electrically connected to the high-voltage conductor, but rather senses the electric field with charged particles at a distance from it. Since the particle displacement is read out through changes in scattered light, and the detection signal is led out through the optical cable 6 in the low-potential region, the insulation required for the secondary electrical leads on the high-voltage side can be reduced, and the signal transmission path can be isolated from the high-voltage potential. This enables the device to function as a GIS voltage transformer without the need to use traditional iron cores or capacitive voltage dividers to create secondary voltage measurement conditions.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations can be made to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A broadband GIS voltage transformer, characterized in that, include: Metal casing, electrically connected to a reference potential; An insulating support member is hermetically connected to the metal housing, and the insulating support member and the metal housing together form an insulating gas chamber filled with insulating gas; A high-voltage conductor passes through the insulating support member. Its first end is electrically connected to the primary equipment outside the metal shell, and its second end is disposed in the insulating air chamber, forming a spatial electric field between it and the metal shell that varies with the primary voltage carried by the high-voltage conductor. The capacitor voltage divider mutual inductor module includes electrodes, voltage divider capacitors, and an electronic acquisition unit; The electrode is disposed in the insulating gas chamber, and is spaced apart from the high-voltage conductor in the middle section between the first end and the second end, forming a coupling capacitor with the high-voltage conductor; the two ends of the voltage dividing capacitor are electrically connected to the electrode and the metal shell respectively; the electronic acquisition unit acquires the voltage divided across the voltage dividing capacitor and outputs a first detection signal characterizing the primary voltage; A suspended photoelectric field sensing module is disposed at an interval between the high-voltage conductor and the insulating air chamber. It outputs a second detection signal characterizing the primary voltage based on the motion response of charged suspended particles under the action of the spatial electric field. The signal processing module is connected to the electronic acquisition unit and the levitated photoelectric field sensing module. Based on the first detection signal and the second detection signal, it determines the voltage components in the primary voltage whose frequencies are in the first frequency range and the second frequency range, respectively, where the second frequency range is higher than the first frequency range.

2. The broadband GIS voltage transformer according to claim 1, characterized in that, The electrode is a cylindrical electrode disposed around the middle section of the high-voltage conductor, the cylindrical electrode having an axial opening toward a second end of the high-voltage conductor, the second end extending from the axial opening and located outside the axial coverage area of ​​the cylindrical electrode.

3. The broadband GIS voltage transformer according to claim 1, characterized in that, The second end of the high-voltage conductor forms a spherical end.

4. The broadband GIS voltage transformer according to claim 1, characterized in that, The suspended photoelectric field sensing module includes an insulating sensor housing, an optical constraint unit, charged suspended particles, and an optical detection unit. A vacuum environment is formed inside the insulating sensor housing. The optical constraint unit is used to constrain the charged suspended particles to a predetermined position within the insulating sensor housing. The optical detection unit is used to detect the motion response of the charged suspended particles under the action of the spatial electric field and output the second detection signal.

5. The broadband GIS voltage transformer according to claim 4, characterized in that, The optical detection unit is used to receive the scattered light generated by the charged suspended particles under laser irradiation, and to generate the second detection signal according to the changes in the scattered light.

6. The broadband GIS voltage transformer according to claim 5, characterized in that, The change in the scattered light includes at least one of the changes in the position of the light spot and the phase change, and the second detection signal is used to characterize the displacement response of the charged suspended particles.

7. The broadband GIS voltage transformer according to claim 1, characterized in that, The suspended photoelectric field sensing module is disposed in the insulating chamber on the side opposite to the insulating support.

8. The broadband GIS voltage transformer according to claim 1, characterized in that, When the signal processing module determines a voltage component in the primary voltage that is higher than the first frequency range based on the second detection signal, it determines the displacement response of the charged suspended particle based on the second detection signal, determines the electric field force on the charged suspended particle based on the displacement response and a predetermined relationship between the particle mechanical response, determines the electric field parameters at a predetermined position based on the electric field force and the charge of the charged suspended particle, and determines the primary voltage based on the correspondence between the electric field parameters and the primary voltage.

9. The wideband GIS voltage transformer according to claim 8, characterized in that, The particle mechanical response relationship is calculated from the mass of the charged suspended particle, the resonant frequency of the charged suspended particle, and the damping coefficient.

10. The broadband GIS voltage transformer according to claim 1, characterized in that, The insulating gas is sulfur hexafluoride gas.

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