High-frequency ultrahigh-voltage pulse voltage and current transformer

Abstract

The invention discloses a high-frequency ultrahigh-voltage pulse voltage and current transformer which is provided with an annular high-frequency pulse current measuring coil assembly surrounding a central ultrahigh-voltage conductor, and the outer layer of the high-frequency pulse current measuring coil assembly is wrapped with a double-shielding layer. The high-frequency ultrahigh-voltage pulse voltage and current transformer is characterized in that the high-frequency pulse current measuring coil assembly comprises a magnetic core, a coil, a distributed load, a planar conductor, a current sampling semi-rigid coaxial cable, a current sampling load compensation resistor and a winding insulating material. The measuring precision is high in performance, stable and reliable, the production and processing cost is extremely low, wireless induction is achieved, and installation is convenient and fast.

Description

Technical Field

[0001] The invention relates to the field of ultra-high voltage pulse power electronic equipment, and in particular to a high-frequency ultra-high voltage pulse voltage and current transformer for ultra-high voltage pulse power electronic equipment. Background Art

[0002] As high-voltage pulse power electronic technology is widely used in medical accelerators, commercial irradiation, industrial accelerators, radar transmitters, synchrotron radiation sources, high-energy physics research, life science research, biopharmaceuticals, artificial nuclear reaction technology, as well as security inspection, flaw detection and other high-voltage pulse power electronic equipment, production and scientific research require high-fidelity and precise measurement of the pulse ultra-high voltage and high-frequency pulse current of a large number of high-voltage pulse power electronic equipment.

[0003] Since the pulse voltage of high-frequency ultra-high voltage pulse power electronic equipment is relatively high, and there is a relatively complex electromagnetic environment around high-frequency pulse ultra-high voltage equipment, the solutions commonly used in China for online monitoring of pulse ultra-high voltage and high-frequency pulse current of pulse power electronic equipment are:

[0004] 1. Pulse ultra-high voltage measurement: The pulse ultra-high voltage is introduced into the coaxial capacitor voltage divider or parallel plate capacitor voltage divider through wiring to monitor the pulse high voltage online. Such capacitor voltage dividers need to use oil-immersed, insulating gas sealed and insulating resin infused structures; whether it is oil-immersed or insulating gas sealed capacitor voltage dividers, they all have a large shell when designed, resulting in a large proportion of the capacitor voltage divider to the overall equipment volume and weight, high cost, inconvenient and fast installation, and affecting the overall miniaturization design of high-voltage pulse power electronic equipment;

[0005] 2. High-frequency pulse current measurement: Due to the limitations of existing technology, high-frequency pulse current sampling usually only requires a common current transformer to be inserted into the low-voltage end of the pulse power electronic equipment (its internal circuit schematic diagram is shown in the figure). Figure 3 Sampling measurement is performed. This measurement scheme causes the measured high-frequency pulse current waveform to be affected by the electromagnetic environment and distributed parameters, resulting in waveform overshoot, oscillation, deformity or distortion, and the inability to accurately perform online measurement.

[0006] The current transformer that samples at the ultra-pulse high-voltage end requires a large inner diameter to ensure the withstand voltage. When the diameter is very large, it receives a lot of surrounding high-frequency interference signals, resulting in distortion of the high-frequency pulse current sampling waveform and changes in measurement data when the position of the central ultra-high voltage conductor changes. In extreme cases, the central ultra-high voltage conductor will discharge the pulse current transformer or the charge inside the pulse current transformer will accumulate, causing damage to the measuring instrument. Summary of the invention

[0007] The technical problem to be solved by the present invention is to realize a special component which has a simple structure, a light volume, is quick to install, and can accurately measure pulse ultra-high voltage and high-frequency pulse current at the pulse ultra-high voltage end, namely, a high-frequency ultra-high voltage pulse voltage current transformer.

[0008] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a high-frequency ultra-high voltage pulse voltage current transformer, the transformer is provided with a high-frequency pulse current measurement coil assembly which is annular and surrounds the central ultra-high voltage conductor, the outer layer of the high-frequency pulse current measurement coil assembly is wrapped with a double shielding layer, the high-frequency pulse current measurement coil assembly includes a magnetic core, a coil, a distributed load, a planar conductor, a current sampling semi-rigid coaxial cable, a current sampling load compensation resistor, a winding insulation material, etc., the coil is evenly wound on the annular magnetic core, the distributed load is evenly distributed around the coil, and each coil with the same number of turns is electrically connected to one end of a distributed load, and the other end of each distributed load is connected to the planar conductor, the planar conductor is a circular ring structure arranged on the outside of the coil, and an isolation insulation material is arranged between the planar conductor and the coil, the current generated on the high-frequency pulse current measurement coil assembly extends to the outside of the shielding layer through the current sampling semi-rigid coaxial cable, and the winding insulation material wraps the magnetic core.

[0009] The shielding layer is provided with two layers, namely, a first shielding layer located at the inner layer, and a second shielding layer located at the outer layer. The first shielding layer and the second shielding layer are both circular tubular structures. The first shielding layer and the second shielding layer wrap the high-frequency pulse current measurement coil assembly. An isolation suspension gap is provided between the first shielding layer and the second shielding layer.

[0010] A current sampling output interface is provided outside the second shielding layer, the inner and outer conductors of the current sampling semi-rigid coaxial cable are connected to the core and shell of the current sampling output interface, the outer shell of the current sampling output interface is connected to the first shielding layer through the outer conductor of the semi-rigid coaxial cable, and the current sampling output interface is isolated and suspended from the second shielding layer.

[0011] The anti-short-circuit gap of the first shielding layer is located on the outside of the circular ring, and the anti-short-circuit gap of the second shielding layer is located on the inside of the circular ring. A long arc-shaped gap is formed between the anti-short-circuit gap of the first shielding layer and the anti-short-circuit gap of the second shielding layer to prevent stray magnetic flux from directly passing through the gap and inducing voltage spikes on the coil, causing overshoot or oscillation of the high-frequency pulse current sampling waveform.

[0012] An induction ring, an isolation ring, a matching capacitor C2, and a voltage sampling terminal resistor are provided between the first shielding layer and the second shielding layer. The induction ring corresponds to the central ultra-high voltage conductor through the anti-short circuit gap of the second shielding layer and senses an induction capacitor C1. The distance between the induction ring and the central ultra-high voltage conductor is d, and the diameter of the central ultra-high voltage conductor is D.

[0013] pass and Get the distance d;

[0014] pass Obtain the diameter D of the central ultra-high voltage conductor;

[0015] Where S is the sensing area, ε is the dielectric constant, n is the voltage divider ratio, C1 is the sensing capacitor, C2 is the matching capacitor, U p is the ultra-high voltage pulse voltage value, E max is the maximum electric field intensity on the electrode surface.

[0016] One end of the matching capacitor is connected to the induction ring, and the other end is connected to the second shielding layer and the outer conductor of the voltage sampling semi-rigid coaxial cable. One end of the voltage sampling terminal resistor is connected to the induction ring and the other end is connected to the inner conductor of the voltage sampling semi-rigid coaxial cable. The inner and outer conductors of the voltage sampling semi-rigid coaxial cable are then connected to the core and shell of the voltage sampling output interface. The voltage sampling output interface is isolated and suspended from the first shielding layer.

[0017] The voltage sampling output interface and the current sampling output interface are N-type interfaces, BNC interfaces or SAM interfaces.

[0018] The first shielding layer is filled with a potting insulating material, and the first shielding layer and the second shielding layer are filled with a potting insulating material. The potting insulating material is an insulating material with a low dielectric constant, oil resistance, and radiation resistance.

[0019] The magnetic core is a high permeability magnetic core, the current sampling load compensation resistor is a high-power, low-temperature drift, high-precision, non-inductive resistor, and the winding insulation material is an insulating paper or insulating film with a low dielectric constant.

[0020] The high-frequency ultra-high voltage pulse voltage and current transformer of the present invention has the functions of ultra-high voltage pulse voltage sampling and high-frequency pulse current sampling, which provides necessary conditions for the miniaturization design of high-voltage pulse power electronic equipment, and specifically has the following advantages:

[0021] 1. It solves the problems of large size, difficulty in processing and producing structural parts, and high design and production costs of traditional capacitor voltage dividers such as oil-immersed capacitor voltage dividers, insulating gas sealed capacitor voltage dividers, and insulating resin infused capacitor voltage dividers. In addition, the high-frequency ultra-high voltage pulse voltage current transformer does not need to introduce the pulse high voltage into the high-frequency ultra-high voltage pulse voltage current transformer through wiring. The high-frequency ultra-high voltage pulse voltage current transformer can be directly wrapped around the central ultra-high voltage conductor loop to achieve the measurement of ultra-high voltage pulse voltage;

[0022] 2. Solved the problem of high-frequency pulse current sampling waveform distortion or overshoot when sampling at the high-voltage end of ultra-high voltage pulse;

[0023] 3. Solved the problem of damage to the test instrument caused by the discharge of the central ultra-high voltage conductor to the high-frequency pulse current transformer or the accumulation of charge inside the high-frequency pulse current transformer when sampling at the high-voltage end of the ultra-high voltage pulse;

[0024] 4. The problem of high-frequency pulse current transformer being placed in the central ultra-high voltage conductor loop and requiring a large inner diameter to ensure withstand voltage is solved. When the diameter is large, a lot of surrounding high-frequency interference signals are received, resulting in distortion of the high-frequency pulse current sampling waveform and changes in measurement data when the position of the central ultra-high voltage conductor changes.

[0025] Therefore, the high-frequency ultra-high voltage pulse voltage current transformer has the advantages of multiple functions, very small size, low cost, high performance, stable and reliable measurement accuracy, extremely low production and processing cost, wireless induction, and convenient and fast installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The following is a brief description of the contents expressed in each figure in the specification of the present invention and the marks in the figure:

[0027] Figure 1 , 2 It is a schematic diagram of the overall structure of the high-frequency ultra-high voltage pulse voltage current transformer of the present invention;

[0028] Figure 3 It is a schematic diagram of an equivalent circuit of a high-frequency ultra-high voltage pulse voltage and current transformer of the present invention;

[0029] Figure 4 It is the equivalent circuit principle diagram of the common current transformer in the prior art;

[0030] Figure 5 The equivalent circuit principle diagram of the high-frequency pulse current measurement coil assembly of the present invention;

[0031] Figure 6 , 7 This is a structural diagram of a high-frequency pulse current measurement coil assembly of the present invention;

[0032] Figure 8 The high-frequency pulse current measurement coil component structure of the present invention Figure 6 AA section view of the middle edge Figure II ;

[0033] Fig. 9 The high-frequency ultra-high voltage pulse voltage current transformer of the present invention Figure 1 Partial detailed view I of the section along the middle line BB;

[0034] The marks in the above figures are: 1. Central ultra-high voltage conductor; 2. High-frequency pulse current measurement coil assembly; 3. First shielding layer; 4. Second shielding layer; 5. Voltage sampling semi-rigid coaxial cable; 6. Current sampling semi-rigid coaxial cable; 7. Isolation mounting plate; 8. Current sampling output interface; 9. Induction ring; 10. Isolation ring; 11. Matching capacitor; 12. Voltage sampling terminal resistor; 13. Voltage sampling output interface; 14. Voltage shielding tube; 15. Current shielding tube; 16. Magnetic core; 17. Coil; 18. Distributed load; 19. Planar conductor; 20. Current sampling load compensation resistor; 21. Winding insulation material; 22 First shielding layer anti-short-circuit gap; 23 Second shielding layer anti-short-circuit gap; 24. Injection insulation material. DETAILED DESCRIPTION

[0035] The following is a further detailed description of the specific implementation methods of the present invention, such as the shape, structure, relative position and connection relationship between the various components involved, the function and working principle of each part, the manufacturing process and operation method, etc., through the description of the embodiments with reference to the accompanying drawings, so as to help those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0036] The high-frequency ultra-high voltage pulse voltage and current transformer of the present invention is used for measuring ultra-high voltage pulse voltage and high-frequency pulse current, and solves the problems of large size, heavy weight, complex structure, difficult production and assembly, and convenient use of oil-immersed capacitor voltage dividers, insulating gas sealed capacitor voltage dividers, and insulating resin infusion capacitor voltage dividers. It can also greatly reduce production costs and improve production efficiency, providing necessary conditions for miniaturized design of high-voltage pulse power electronic equipment, and solves the problem of distortion or overshoot of high-frequency pulse current sampling waveform when sampling at the ultra-high voltage pulse high-voltage end; solves the problem of damage to the measuring instrument when the central ultra-high voltage conductor discharges the high-frequency pulse current transformer or the internal charge accumulation of the high-frequency pulse current transformer when sampling at the ultra-high voltage pulse high-voltage end; solves the influence of the central ultra-high voltage conductor position change on the distortion of the high-frequency pulse current sampling waveform and the change of measurement data when sampling at the high-voltage end.

[0037] The high-frequency ultra-high voltage pulse voltage current transformer consists of a high-frequency pulse current measurement coil assembly 2, a first shielding layer 3, a second shielding layer 4, a voltage sampling semi-rigid coaxial cable 5, a current sampling semi-rigid coaxial cable 6, an isolation mounting plate 7, a current sampling output interface 8, an induction ring 9, an isolation ring 10, a matching capacitor 11, a voltage sampling terminal resistor 12, a voltage sampling output interface 13, a voltage shielding tube 14, a current shielding tube 15, a first shielding anti-short-circuit gap 22, a second shielding anti-short-circuit gap 23, a perfusion insulation material 24, etc., wherein the high-frequency pulse current measurement coil assembly equivalent circuit structure consists of a magnetic core 16, a coil 17, a distributed load 18, a planar conductor 19, a current sampling semi-rigid coaxial cable 6, a current sampling load compensation resistor 20, a winding insulation material 21, etc. The high-frequency pulse current coil assembly is designed with double-layer shielding to prevent the central ultra-high voltage conductor from discharging the high-frequency pulse voltage current transformer or the accumulation of charge on the high-frequency pulse voltage current transformer when sampling at the high-voltage end of the ultra-high voltage pulse, causing damage to the measuring instrument, and the influence of the position change of the central ultra-high voltage conductor on the high-frequency pulse current sampling waveform and the change of measurement data when sampling at the high-voltage end. The second layer of shielding also serves as a shielding layer for ultra-high voltage pulse voltage sampling, that is, the ultra-high voltage pulse voltage sampling is single-shielded.

[0038] The magnetic core 16 is made of soft magnetic material with high magnetic permeability, such as ferrite material or nanocrystalline material; the magnetic core 16 is coated with insulating material 21, and the coil 17 is evenly wound on the magnetic core 16 with enameled wire; there is insulating material 21 between the magnetic core 16 and the coil 17 for insulation isolation; the planar conductor 19 is tightly attached to the surface of the coil 17, and an insulating material 21 is provided between the planar conductor 19 and the coil 17 for isolation, the distributed load 18 is evenly welded on the outer periphery of the coil 17, one end is welded on the coil 17, and the other end is welded on the planar conductor 19, the current sampling load compensation resistor 20 is connected to the two ends of the coil and is connected to the current sampling output interface 8 core and the shell through the inner and outer conductors of the semi-rigid coaxial cable 6.

[0039] The high-frequency pulse current measurement coil assembly 2 is centrally installed in the first shielding layer 3, and the current sampling semi-rigid coaxial cable 6 on the high-frequency pulse current measurement coil assembly 2 is led out of the first shielding layer 3. The first shielding layer 3 is completely filled with an insulating material 24, and the insulating material 24 is an insulating material with low dielectric constant, oil resistance, and radiation resistance. The isolation ring 10 is fixed on the surface of the first shielding layer 3. Figure 1 and Figure 7The position shown in the figure is shown, and the induction ring 9 is fixed in the corresponding groove of the isolation ring 10, and then installed in the second shielding layer 4. The voltage shielding tube 14 and the current shielding tube 15 are welded at the corresponding positions of the second shielding layer 4, and the voltage sampling output interface 13 is installed on the voltage shielding tube 14; the current sampling output interface 8 is installed on the current shielding tube 15 and the isolation mounting plate 7 and the current sampling output interface 8 is isolated from the current shielding tube 15; the matching capacitor 11 is a low temperature drift and high precision capacitor, one end of the matching capacitor 11 is connected to the induction ring 9, and the other end is connected to the second shielding layer 4 and the outer conductor of the voltage sampling semi-rigid coaxial cable 5; the induction ring 9 is set on the isolation ring 10 between the first shielding layer 3 and the second shielding layer 4, and the capacitance C1 is sensed corresponding to the central ultra-high voltage conductor through the gap of the second shielding layer 4.

[0040] The voltage sampling terminal resistor 11 is a low temperature drift high precision resistor. One end of the voltage sampling terminal resistor 11 is connected to the induction ring 9 and the other end is connected to the inner conductor of the voltage sampling semi-rigid coaxial cable 5; the inner and outer conductors of the voltage sampling semi-rigid coaxial cable 5 are then connected to the core and shell of the voltage sampling output interface 13; the gap between the first shielding layer 3 and the second shielding layer 4 is completely filled with insulating material 24, and the filled insulating material 24 is an insulating material with low dielectric constant, oil resistance, and radiation resistance. The voltage or current sampling output interface is not limited to the N-type interface, but can also be a BNC interface or a SAM interface, etc.

[0041] The first shielding layer 3 and the second shielding layer 4 have an appearance as follows Figure 1 and Figure 7 As shown, because it is to be installed in a pulsed ultra-high voltage environment, a circular ring structure with a circular cross-section is adopted to reduce the surface electric field strength and prevent tip discharge. The anti-short-circuit gap 22 of the first shielding layer 3 is located on the outside of the circular cross-section of the first shielding layer 3. The first shielding layer 3 and the second shielding layer 4 are both formed by welding two upper and lower semicircular rings, and both have semi-rigid coaxial cable through-holes and injection process holes. The anti-short-circuit gap 23 of the second shielding layer 4 is located on the inner side of the circular cross-section of the second shielding layer 4 and corresponds to the central ultra-high voltage conductor 1. A long arc gap is formed between the anti-short-circuit gap 22 of the first shielding layer 3 and the anti-short-circuit gap 23 of the second shielding layer 4 to prevent stray magnetic flux from directly passing through the gap to induce voltage spikes on the coil and cause overshoot of the high-frequency pulse current sampling waveform.

[0042] When the high-frequency ultra-high voltage pulse voltage and current transformer is used, it should be placed in the central ultra-high voltage conductor 1 loop of the high-voltage pulse equipment. An inductive capacitor C1 will be generated between the central ultra-high voltage conductor 1 and the inductive ring 9. The distance between the inductive ring 9 and the central ultra-high voltage conductor 1 is d, and the diameter of the central ultra-high voltage conductor 1 is D.

[0043] pass and Get the distance d;

[0044] pass Obtain the diameter D of the central ultra-high voltage conductor;

[0045] (Where S is the sensing area, ε is the dielectric constant, n is the voltage divider ratio, C1 is the sensing capacitor, C2 is the matching capacitor, U p is the ultra-high voltage pulse voltage value, E max is the maximum electric field strength on the electrode surface)

[0046] The high frequency ultra-high voltage pulse voltage current transformer has the following advantages:

[0047] 1. The high-frequency ultra-high voltage pulse voltage and current transformer is placed in the central ultra-high voltage conductor loop. It can accurately measure pulse ultra-high voltage and high-frequency pulse current at the same time. It has a small size and a simple installation structure, which provides the necessary conditions for the miniaturization design of high-voltage pulse power electronic equipment.

[0048] 2. The high-frequency ultra-high voltage pulse voltage and current transformer adopts wireless induction technology. When measuring the pulse ultra-high voltage, it is not necessary to connect the pulse ultra-high voltage to the high-frequency ultra-high voltage pulse voltage and current transformer; an induction capacitor C1 is induced between the central ultra-high voltage conductor and the induction ring. According to the equivalent circuit of the present invention Figure 2 By adjusting the capacitance value of C2, the voltage divider ratio can be adjusted to achieve the measurement of pulse ultra-high voltage.

[0049] 3. The high-frequency ultra-high voltage pulse voltage and current transformer adopts distributed load technology, which can be placed on the central ultra-high voltage conductor loop to accurately measure the high-frequency pulse current, solving the problem of oscillation, overshoot and distortion of the high-frequency pulse current waveform when measuring the high-voltage end of the ordinary current transformer.

[0050] 4. The high-frequency ultra-high voltage pulse voltage and current transformer adopts a double shielding structure; the first shielding layer and the second shielding layer both adopt a circular ring structure with a circular cross-section. When sampling at the high-voltage end of the ultra-high voltage pulse, the central ultra-high voltage conductor discharges the high-frequency pulse current transformer or the internal charge accumulation of the high-frequency pulse current transformer damages the measuring instrument. It is suitable for working in an ultra-high voltage environment.

[0051] 5. The first shielding layer anti-short-circuit gap of the high-frequency ultra-high voltage pulse voltage current transformer is on the outside of the ring, and the second shielding layer anti-short-circuit gap is on the inside of the ring. A long arc gap is formed between the first shielding layer and the second shielding layer anti-short-circuit gap to prevent stray magnetic flux from directly passing through the gap to induce voltage spikes on the coil and cause overshoot of the high-frequency pulse current sampling waveform.

[0052] 6. The high-frequency ultra-high voltage pulse voltage and current transformer solves the problem that a large inner diameter is required to ensure the withstand voltage. When the diameter is large, a lot of surrounding high-frequency interference signals are received, resulting in distortion of the high-frequency pulse current sampling waveform and change in measurement data when the position of the central ultra-high voltage conductor changes.

[0053] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A high-frequency ultra-high voltage pulse voltage current transformer, the transformer is provided with a high-frequency pulse current measurement coil assembly which is annular and surrounds a central ultra-high voltage conductor, the outer layer of the high-frequency pulse current measurement coil assembly is wrapped with a double shielding layer, characterized in that: The high-frequency pulse current measurement coil assembly includes a magnetic core, a coil, a distributed load, a planar conductor, a current sampling semi-rigid coaxial cable, a current sampling load compensation resistor, and a winding insulation material. The coil is evenly wound on the annular magnetic core, the distributed load is evenly distributed around the coil, and each coil with the same number of turns is electrically connected to one end of a distributed load, and the other end of each distributed load is connected to the planar conductor. The planar conductor is a circular ring structure and is arranged outside the coil. An isolation insulation material is provided between the planar conductor and the coil. The current generated by the high-frequency pulse current measurement coil assembly extends to the outside of the shielding layer through the current sampling semi-rigid coaxial cable, and the winding insulation material wraps the magnetic core.

2. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 1, characterized in that: The shielding layer is provided with two layers, namely, a first shielding layer located at the inner layer, and a second shielding layer located at the outer layer. The first shielding layer and the second shielding layer are both circular tubular structures. The first shielding layer and the second shielding layer wrap the high-frequency pulse current measurement coil assembly. An isolation suspension gap is provided between the first shielding layer and the second shielding layer.

3. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 2, characterized in that: A current sampling output interface is provided outside the second shielding layer, the inner and outer conductors of the current sampling semi-rigid coaxial cable are connected to the core and shell of the current sampling output interface, the outer shell of the current sampling output interface is connected to the first shielding layer through the outer conductor of the semi-rigid coaxial cable, and the current sampling output interface is isolated and suspended from the second shielding layer.

4. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 3, characterized in that: The anti-short-circuit gap of the first shielding layer is located on the outside of the circular ring, and the anti-short-circuit gap of the second shielding layer is located on the inside of the circular ring. A long arc-shaped gap is formed between the anti-short-circuit gap of the first shielding layer and the anti-short-circuit gap of the second shielding layer to prevent stray magnetic flux from directly passing through the gap and inducing voltage spikes on the coil, causing overshoot or oscillation of the high-frequency pulse current sampling waveform.

5. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 4, characterized in that: An induction ring, an isolation ring, a matching capacitor C2, and a voltage sampling terminal resistor are provided between the first shielding layer and the second shielding layer. The induction ring corresponds to the central ultra-high voltage conductor through the anti-short circuit gap of the second shielding layer and senses an induction capacitor C1. The distance between the induction ring and the central ultra-high voltage conductor is d, and the diameter of the central ultra-high voltage conductor is D. pass and Get the distance d; pass Obtain the diameter D of the central ultra-high voltage conductor; Where S is the sensing area, ε is the dielectric constant, n is the voltage divider ratio, C1 is the sensing capacitor, C2 is the matching capacitor, U p is the ultra-high voltage pulse voltage value, E max is the maximum electric field intensity on the electrode surface.

6. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 5, characterized in that: One end of the matching capacitor is connected to the induction ring, and the other end is connected to the second shielding layer and the outer conductor of the voltage sampling semi-rigid coaxial cable. One end of the voltage sampling terminal resistor is connected to the induction ring and the other end is connected to the inner conductor of the voltage sampling semi-rigid coaxial cable. The inner and outer conductors of the voltage sampling semi-rigid coaxial cable are then connected to the core and shell of the voltage sampling output interface. The voltage sampling output interface is isolated and suspended from the first shielding layer.

7. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 6, characterized in that: The voltage sampling output interface and the current sampling output interface are N-type interfaces, BNC interfaces or SAM interfaces.

8. The high-frequency ultra-high voltage pulse voltage current transformer according to any one of claims 2 to 7, characterized in that: The first shielding layer is filled with a potting insulating material, and the first shielding layer and the second shielding layer are filled with a potting insulating material. The potting insulating material is an insulating material with a low dielectric constant, oil resistance, and radiation resistance.

9. The high-frequency ultra-high voltage pulse voltage current transformer according to claim 8, characterized in that: The magnetic core is a high permeability magnetic core, the current sampling load compensation resistor is a high-power, low-temperature drift, high-precision, non-inductive resistor, and the winding insulation material is an insulating paper or insulating film with a low dielectric constant.

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