High voltage measuring device

Abstract

The invention relates to the field of high voltage measurement, in particular to a high voltage measuring device which comprises a quartz vacuum discharge tube, a vacuum control system, a positive electrode, a negative electrode, an external magnet, an internal magnet, a grating ruler, a photodiode and a digital display. Wherein the positive electrode and the negative electrode are arranged in the quartz vacuum discharge tube. And the annular external magnet is arranged outside the quartz vacuum discharge tube. The built-in magnet is installed on the positive electrode, and the grating ruler and the photodiode are connected to the digital display through wires. And the vacuum control system is connected with the quartz vacuum discharge tube through a vacuum pipeline. The device has the technical advantages that a stable gas discharge environment is constructed by utilizing a vacuum system, and high-precision measurement of high voltage of more than million volts is realized in cooperation with a magnetic transmission and high-precision digital circuit measurement mode.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage measurement, and particularly to a high-voltage measurement device. Background Art

[0002] 1. Ultra-high voltage measurement technology: In the fields of power systems, high-voltage equipment testing, and scientific research, the accurate measurement of high voltages (especially voltages above one million volts) is crucial. Traditional high-voltage measurement methods usually rely on voltage dividers or capacitive voltage transformers, but these methods have limitations when measuring extremely high voltages, such as large volume, susceptibility to external interference, or difficulty in ensuring measurement accuracy. With the development of modern high-voltage generating instruments, particle accelerators, and extra-high voltage power systems, the demand for high-precision voltage measurement above one million volts is also becoming increasingly urgent. Traditional voltage measurement devices often have problems such as inaccurate measurement and poor stability when facing ultra-high voltages, and cannot meet the requirements of modern power systems. Therefore, it is particularly important to develop a device that can accurately measure in the order of one million volts.

[0003] 2. Common high-voltage measurement methods: Electrostatic force measurement When measuring high voltage using electrostatic force, a voltage u is applied between two special electrodes, and the electrodes will be subjected to the action of electrostatic force f. Moreover, the magnitude of f has a fixed relationship with the value of u. Therefore, by measuring the magnitude of f or the displacement or deflection of the movable plate caused by it, the magnitude of the applied voltage u can be determined. The instrument made based on this principle is an electrostatic voltmeter, which can be used to measure low voltages and can also be applied in high-voltage measurement. The upper limit of the directly measurable voltage can reach 500 - 600 kV.

[0004] Voltage divider measurement When the measured voltage is very high, a high-voltage electrostatic voltmeter cannot directly measure it. In addition, when it is necessary to measure the waveform of the voltage using an oscilloscope, the very high measured voltage cannot be directly led to the oscilloscope. In the above situations, using a high-voltage voltage divider to divide out a small part of the voltage and then using measuring instruments such as electrostatic voltmeters, peak voltmeters, and high-voltage pulse oscilloscopes for measurement is the most reasonable solution. Voltage dividers can be used to measure voltages from several thousand volts to several million volts, but voltage dividers often have complex structures, large volumes, and are prone to breakdown and damage, which limits the application of voltage dividers in the field of high-voltage measurement.

[0005] Mutual inductance measurement The direct measurement method of high-voltage voltage transformers is to directly connect the primary winding of the transformer to the high-voltage power supply, and connect the secondary winding to a voltmeter or ammeter. The turns ratio of the high-voltage voltage transformer is calculated by measuring the voltage or current. This method has high accuracy and is suitable for transformers with relatively small voltages, but it requires certain voltage experiment experience and operation skills. At the same time, attention should be paid to protection measures to avoid harm to personnel and equipment. The indirect measurement method of high-voltage voltage transformers is to calculate the turns ratio of the transformer by measuring the short-circuit impedance and load impedance of the transformer. Among them, the short-circuit impedance method is to short-circuit the high-voltage side of the transformer and calculate the turns ratio by measuring the current and voltage on the low-voltage side; the load impedance method is to operate the transformer under the rated load and calculate the turns ratio by measuring the high-voltage side voltage and low-voltage side current. This method is simple to operate and is suitable for transformers of various ratios, but the accuracy is relatively low.

[0006] Gas discharge method The discharge sphere gap is a high-voltage limiting and detecting device based on the principle of gas discharge. Its core idea is to use the discharge characteristics of the air gap between two electrodes to limit and measure the voltage. Gas discharge can measure the amplitudes of steady-state high voltages and impulse voltages, and it is the only device for directly measuring ultra-high voltages, with a maximum measured voltage of about 2 MV. Its advantages are simple structure, easy to make or purchase, and not easily damaged. The uncertainty when measuring AC and impulse voltages can reach within ±3%. Its disadvantages are: it must discharge during measurement, and the discharge will destroy the stable state and may cause overvoltage. Gas discharge has statistical properties, and the data is scattered. The average value of multiple discharge data must be taken. To prevent the influence of free gas, the discharge interval each time should not be too small, and the voltage rise rate during the voltage rise process should be relatively slow, so that the low-voltage meter can accurately read the value at the moment of sphere gap discharge, and the measurement takes more time. In actual use, a calibration curve needs to be made for measuring steady-state voltages, and the 50% discharge voltage method is used for measuring impulse voltages, and the procedures are all relatively troublesome. The atmospheric conditions need to be calibrated. Generally speaking, the measuring sphere gap is not suitable for outdoor use. Practice has proved that due to the influence of strong airflows, as well as dust, sand, fibers, and high humidity, abnormal discharges often occur when using the sphere gap outdoors.

[0007] In summary, the traditional discharge sphere gap device has deficiencies in accurately controlling the discharge gap distance, stability in a vacuum environment, and degree of intelligence. Therefore, there is an urgent need for a high-precision and high-stability discharge sphere gap device that can accurately measure voltages above one million volts. Summary of the Invention

[0008] The purpose of the present invention is to solve the deficiencies existing in the prior art and propose a high-voltage measuring device.

[0009] To achieve the above purpose, the present invention adopts the following technical solutions: A high-voltage measuring device includes a quartz vacuum discharge tube, a vacuum control system, a positive electrode, a negative electrode, an external magnet, a grating scale, a photodiode, and a digital display. The vacuum control system consists of a vacuum pump, a gas pressure regulating valve, and a vacuum gauge, and supplies a gas medium to the quartz vacuum tube through an air extraction port on the negative electrode vacuum chuck. The positive electrode consists of a discharge sphere, a telescopic rod, an internal magnet, a high-voltage terminal, and a vacuum insulating chuck. The discharge sphere is designed in a spherical shape. The positive discharge sphere is connected to the insulating terminal through a telescopic rod to reduce the tip effect and ensure a uniform electric field distribution.

[0010] In addition, preferably, the discharge sphere of the positive electrode is designed in a spherical shape to reduce the tip effect and ensure a uniform electric field distribution.

[0011] In addition, preferably, an indicating arrow is installed on the external magnet, which is connected to the grating scale. The resolution of the grating scale is ≤0.1 mm, and it is used to accurately measure the position change of the indicating arrow.

[0012] In addition, preferably, the internal magnet of the positive electrode can move inside the vacuum tube under the magnetic force of the external magnet. The internal magnet of the positive electrode can move inside the vacuum tube under the magnetic force of the external magnet, and at the same time drive the telescopic rod and the discharge sphere to realize the adjustment of the discharge gap.

[0013] In addition, preferably, the photodiode is installed close to the discharge gap, and the photoelectric response time is ≤1 μs, which can detect the fast and weak flash signal generated by the discharge.

[0014] In addition, preferably, the detection circuit of the digital display calculates the voltage value according to Paschen's law formula U = f(P, d) (where P is the gas pressure, d is the discharge gap distance, and f is the characteristic coefficient), and outputs the voltage value through the digital display screen.

[0015] The beneficial effects of the present invention are as follows: 1. The present invention uses a quartz vacuum tube, a high-purity gas medium, and a vacuum degree control system to achieve a high-stability and high-repeatability discharge environment.

[0016] 2. Through the cooperation of the grating scale and the photodiode, the discharge gap and the flash signal are accurately measured, ensuring high-precision measurement.

[0017] 3. The magnetic drive is adopted to freely adjust the discharge gap, and the vacuum system adjusts the working pressure and the discharge medium, which can meet the measurement requirements of different voltage ranges.

[0018] 4. Compared with the traditional high-voltage measuring device, the present invention realizes miniaturization and digitization, which is convenient for users to operate. Description of the Drawings

[0019] Figure 1 It is a structural disassembly diagram of a high-voltage measurement device; Figure 2 It is a schematic structural diagram of a discharge sphere electrode; Figure 3 It is a schematic diagram of the use of a high-voltage measurement device.

[0020] In the figure: 1. High-voltage terminal; 2. Positive electrode; 3. Quartz vacuum tube; 4. External magnet; 5. Photodiode; 6. Negative electrode; 7. Display; 8. Grating scale; 201. Positive electrode telescopic rod; 202. Internal magnet; 203. Positive electrode discharge sphere; 601. High-voltage terminal; 602. Vacuum chuck; 603. Negative electrode discharge sphere; 604. Vacuum pumping port; 1. High-voltage terminal; 2. Telescopic rod; 3. External magnet; 4. Positive electrode discharge sphere; 5. Photodiode; 6. Negative electrode discharge sphere; 7. Display; 8. Grating scale. Specific implementation manners

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0022] Referring to Figures 1-3 , a high-voltage measurement device includes 1. Quartz vacuum discharge tube, vacuum control system, positive electrode, negative electrode, external magnet, grating scale, photodiode, digital display. It is characterized in that the vacuum control system is composed of a vacuum pump, a pressure regulating valve, and a vacuum gauge, and supplies a gas medium to the quartz vacuum tube through the air extraction port on the negative electrode vacuum chuck; The positive electrode is composed of a discharge sphere, a telescopic rod, an internal magnet, a high-voltage terminal, and a vacuum insulating chuck. The discharge sphere adopts a spherical design. The positive electrode discharge sphere is connected to the insulating terminal through a telescopic rod to reduce the tip effect and ensure a uniform electric field distribution.

[0023] Moreover, the discharge sphere of the positive electrode adopts a spherical design to reduce the tip effect and ensure a uniform electric field distribution.

[0024] At the same time, an indicating arrow is installed on the external magnet and is connected to the grating scale. The resolution of the grating scale ≤ 0.1 mm, which is used to accurately measure the position change of the indicating arrow.

[0025] At the same time, the internal magnet of the positive electrode can move inside the vacuum tube under the magnetic force of the external magnet. The internal magnet of the positive electrode can move inside the vacuum tube under the magnetic force of the external magnet, and at the same time drive the telescopic rod and the discharge sphere to realize the adjustment of the discharge gap.

[0026] Furthermore, the installation position of the photodiode is close to the discharge gap, and the photoelectric response time ≤ 1 μs, which can detect the fast and weak flash signals generated by the discharge.

[0027] Moreover, the detection circuit of the digital display calculates the voltage value according to Paschen's law formula U = f(P, d) (where P is the gas pressure, d is the discharge gap distance, and f is the characteristic coefficient), and outputs the voltage value through the digital display screen.

[0028] Taking the measurement of high voltage around 1 million volts as an example, the implementation method is as follows.

[0029] Preparation work: Install the quartz vacuum discharge tube, vacuum pump, and resistance vacuum gauge in place to ensure the airtightness of the system. Install the detection alligator clip on the positive terminal, and the negative terminal is grounded. Connect the nitrogen cylinder and the gas path of the vacuum control system to the air extraction port of the negative electrode. Select nitrogen as the discharge gas medium on the digital display. Air pressure adjustment: Start the vacuum pump to evacuate the air, introduce high-purity nitrogen for washing three times repeatedly, then increase the nitrogen pressure to the order of 300 KPa, monitor the air pressure value in real time through the vacuum gauge, and input the air pressure parameter P into the detection circuit.

[0030] Spacing adjustment: Through the cooperation of the external magnet sliding module and the internal magnet sliding module, adjust the distance d between the discharge ball electrodes from the maximum to the minimum. The indicating arrow moves on the external magnet sliding module, and the grating ruler measures its position change.

[0031] Voltage measurement: When the spacing d is small enough and the voltage to be measured exceeds the Paschen's law threshold corresponding to the gas pressure in the tube, gas discharge occurs, generating a short purple flash signal. After the photodiode detects the flash signal, it triggers the detection circuit to read the data of the grating ruler and calculate the voltage value, and finally displays the result through the digital display screen.

[0032] Automatic compensation: The system automatically adjusts the parameters according to the actually measured air pressure and discharge gap to ensure the measurement accuracy.

[0033] In the present invention, a high-stability and high-repeatability discharge environment is realized by using a quartz vacuum tube, a high-purity gas medium, and a vacuum degree control system.

[0034] 2. Through the cooperation of the grating ruler and the photodiode, the discharge gap and the flash signal are accurately measured, ensuring high measurement accuracy.

[0035] 3. The discharge gap is freely adjusted by magnetic drive, and the vacuum system adjusts the working air pressure and discharge medium, which can meet the measurement requirements of different voltage ranges.

[0036] 4. Compared with the traditional high-voltage measurement device, the present invention realizes miniaturization and digitization, which is convenient for users to operate.

[0037] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. A high voltage measuring device, comprising a quartz vacuum discharge tube, a vacuum control system, a positive electrode, a negative electrode, an external magnet, a grating ruler, a photodiode, and a digital display, characterized in that: The vacuum control system is composed of a vacuum pump, a gas pressure regulating valve, and a vacuum gauge, and supplies gas medium to the quartz vacuum tube through the air extraction port on the negative electrode vacuum chuck; The positive electrode is composed of a discharge ball, a telescopic rod, a built-in magnet, a high-voltage terminal, and a vacuum insulation chuck. The discharge ball adopts a spherical design, and the positive discharge ball is connected to the insulated terminal through the telescopic rod to reduce the tip effect and ensure uniform electric field distribution.

2. A high voltage measuring device according to claim 1, characterized in that: The discharge ball of the positive electrode adopts a spherical design to reduce the tip effect and ensure uniform electric field distribution.

3. A high voltage measuring device according to claim 1, characterized in that: The external magnet is provided with an indicating arrow and is connected to a grating ruler, the resolution of which is ≤0.1 mm, and is used to accurately measure the position change of the indicating arrow.

4. A high voltage measuring device according to claim 1, characterized in that: The built-in magnet of the positive electrode can be moved in the vacuum tube by the magnetic force of the external magnet, and at the same time drive the telescopic rod and the discharge ball to adjust the discharge gap.

5. A high voltage measuring device according to claim 1, characterized in that: The photodiode is installed close to the discharge gap, and has a photoelectric response time of ≤1 μs, and can detect a fast and weak flash signal generated by the discharge.

6. A high voltage measuring device according to claim 1, characterized in that: The detection circuit of the digital display calculates the voltage value according to the Paschen law formula U = f(P, d) (where P is the gas pressure, d is the discharge gap distance, and f is the characteristic coefficient), and outputs the voltage value through the digital display.

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