Signal sampling structure of high voltage generator

Abstract

The utility model discloses a signal sampling structure of a high-voltage generator, which comprises a polytetrafluoroethylene tube, a voltage booster is sleeved outside the polytetrafluoroethylene tube, and a magnetic bar coil is arranged in the polytetrafluoroethylene tube; the open end of the PTFE tube is fixedly connected with the low-voltage metal plate, and a shielding gasket is arranged between the PTFE tube and the low-voltage metal plate; the low-voltage metal plate and the grounding metal plate form electrical isolation mechanical connection through an insulating washer. The low-voltage end of the booster is electrically connected with the low-voltage metal plate; the high-voltage end of the booster is connected with the high-voltage resistor; the low-voltage end of the high-voltage resistor is connected with one current detection channel of the current detection device, and the input end of the other current detection channel of the current detection device is grounded; and the common end of the two current detection channels is connected with the low-voltage metal plate. The signal sampling device is arranged at the low-voltage end, and shielding measures are added, so that the current measurement precision is greatly improved, and the purposes of detecting the current from the low-voltage end and measuring the micro current with high precision are achieved.

Description

Technical Field

[0001] This utility model belongs to the field of electronic and high voltage measurement technology, and specifically relates to a signal sampling structure for a high voltage generator. Background Art

[0002] The statements herein provide only background information related to this invention and do not necessarily constitute prior art.

[0003] To ensure the safe operation and stable performance of equipment, it is necessary to detect the output voltage and current of the high-voltage generator. In existing technologies, to guarantee measurement accuracy, the current is typically detected at the high-voltage output terminal. This requires isolated power supply to the current detection circuit and communication via isolated transmission. However, when the high-voltage output reaches 80kV or higher, isolated power supply becomes complex and unsafe.

[0004] If current is detected at the low-voltage end, complex isolated power supply and data transmission are not required. However, a significant problem with low-voltage end current detection is insufficient current measurement accuracy. For example, in resistance measurement, the resistance to be measured might be in the TΩ range, but the resistance obtained from measuring the current at the low-voltage end might only be a few hundred MΩ, resulting in a serious deviation in measurement accuracy. This phenomenon is usually caused by various leakage currents and is difficult to eliminate. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a signal sampling structure for a high-voltage generator. The signal sampling device is placed at the low-voltage end, and shielding measures are added to address the inherent susceptibility to interference at the low-voltage end. This greatly improves the accuracy of current measurement, thereby achieving the goal of detecting current at the low-voltage end and measuring minute currents with high precision.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0007] The present invention provides a signal sampling structure for a high-voltage generator, comprising: a PTFE tube, a booster sleeved on the outside of the PTFE tube, and a magnetic rod coil inside the tube; the open end of the PTFE tube is fixedly connected to a low-voltage metal plate, and a shielding gasket is provided between the two; the low-voltage metal plate is also electrically isolated from a grounded metal plate by means of an insulating gasket.

[0008] The low-voltage end of the booster is electrically connected to the low-voltage metal plate; the high-voltage end of the booster is connected to the high-voltage resistor; the low-voltage end of the high-voltage resistor is connected to one current detection channel of the current detection device, and the input end of the other current detection channel of the current detection device is grounded; the common end of the two current detection channels is connected to the low-voltage metal plate.

[0009] In at least one embodiment, the shielding gasket has an inner shielding ring and an outer shielding ring; the outer shielding ring is in direct contact with the low-voltage metal plate; and the inner shielding ring is grounded.

[0010] In at least one embodiment, the shielding gasket is made of a double-layer circuit board, with an inner shielding ring and an outer shielding ring on each side.

[0011] In at least one embodiment, the two inner shielding rings are connected by vias; the two outer shielding rings are connected by vias.

[0012] In at least one embodiment, both the inner and outer shielding rings have gaps.

[0013] In at least one embodiment, the low-pressure metal plate is provided with elongated holes.

[0014] In at least one embodiment, multiple first mounting holes are provided on both the low-pressure metal plate and the shielding washer; the low-pressure metal plate, the shielding washer, and the open end of the PTFE tube are fixedly connected by screws passing through the first mounting holes.

[0015] In at least one embodiment, a plurality of second mounting holes are formed on the outer edge of the low-voltage metal plate; an insulating washer is inserted into the second mounting hole; and the low-voltage metal plate and the grounding metal plate are connected by bolts passing through the second mounting holes.

[0016] In at least one embodiment, the high-voltage resistor is encapsulated in a plastic tube with epoxy resin; the low-voltage end of the plastic tube is connected to the low-voltage metal plate.

[0017] In at least one embodiment, when multiple sets of boost converters, PTFE tubes, and magnetic rod coils are included, the open ends of all PTFE tubes are mounted on the same low-voltage metal plate through their respective shielding washers.

[0018] The beneficial effects of the above-described technical solution of this utility model are as follows:

[0019] This utility model discloses a signal sampling structure for a high-voltage generator. The signal sampling device is placed at the low-voltage end. At the same time, in view of the inherent susceptibility to interference in low-voltage end sampling, shielding measures are added, which greatly improves the accuracy of current measurement. Thus, it can detect current from the low-voltage end and achieve high-precision measurement of minute currents.

[0020] By setting up an independent low-voltage metal plate and shielding gasket, the leakage current IL2 of the booster is led to the low-voltage metal plate to form a circuit with the booster body, and the leakage current IL1 of the magnetic rod coil is led to the ground to prevent it from entering the IX measurement circuit. This eliminates the influence of leakage current, so that only the current IX of the test sample enters the current detection device. The measurement data of RX can be obtained by calculating RX = (RS*IS) / IX using the high-voltage resistor RS and IS, IX. Moreover, the current detection device is located at the low-voltage end, which facilitates the power supply and communication isolation of the current detection device and greatly improves the measurement accuracy. This achieves the goal of detecting current from the low-voltage end and realizing high-precision measurement of small currents. Attached Figure Description

[0021] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0022] Figure 1 This is an overall schematic diagram of the signal sampling structure of a high-voltage generator according to this utility model;

[0023] Figure 2 This is a schematic diagram of the shielding gasket of the signal sampling structure of a high-voltage generator according to this utility model;

[0024] Figure 3 This is a schematic diagram of a low-voltage metal plate representing the signal sampling structure of a high-voltage generator according to this utility model.

[0025] In the diagram: 1. Boost converter; 2. PTFE tube; 3. Magnet coil; 4. High-voltage resistor; 5. Grounding metal plate; 6. Low-voltage metal plate; 7. Insulating washer; 8. Outer shielding ring; 9. Shielding washer; 10. Inner shielding ring; 11. Current detection device.

[0026] The distances or dimensions between parts have been exaggerated to show their positions; the diagram is for illustrative purposes only. Detailed Implementation

[0027] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0028] As described in the background section, the purpose of this utility model is to overcome the shortcomings of the prior art and provide a signal sampling structure for a high-voltage generator. The signal sampling device is placed at the low-voltage end, and shielding measures are added to address the inherent susceptibility to interference at the low-voltage end. This greatly improves the accuracy of current measurement, thereby achieving the goal of detecting current at the low-voltage end and measuring minute currents with high precision.

[0029] Example 1

[0030] like Figures 1-3 As shown, this embodiment discloses a signal sampling structure for a high-voltage generator, including: a booster 1, a PTFE tube 2, a magnetic rod coil 3, a high-voltage resistor 4, a grounding metal plate 5, a low-voltage metal plate 6, an insulating washer 7, a shielding washer 9, and a current detection device 11.

[0031] Specifically, a booster 1 is installed on the outside of the PTFE tube 2, and a magnetic rod coil 3 is installed inside the PTFE tube 2. The magnetic rod coil 3 inserted into the PTFE tube 2 generates an alternating magnetic field under high-frequency drive, and the booster 1 installed on the outside of the PTFE tube 2 generates high voltage and outputs it under the drive of the magnetic field.

[0032] The open end of the PTFE tube 2 is fixedly connected to the low-voltage metal plate 6, and a shielding gasket 9 is provided between them. Since the low-voltage metal plate 6 and the grounding metal plate 5 span across both ends of the IX detection device, they need to be isolated. Therefore, the low-voltage metal plate 6 is also electrically isolated from the grounding metal plate 5 through an insulating gasket 7. The low-voltage end B of the booster 1 is electrically connected to the low-voltage metal plate 6, and the high-voltage end A of the booster 1 is connected to the high-voltage resistor 4. The low-voltage end of the high-voltage resistor 4 is connected to one current detection channel of the current detection device 11. The input end of the other current detection channel of the current detection device 11 is grounded, and the common end of the two current detection channels is connected to the low-voltage metal plate 6.

[0033] The high-voltage resistor 4 is used to detect high voltage. After applying voltage to the high-voltage resistor RS, the high-voltage resistor current IS is obtained. After applying voltage to the external test sample RX, the test sample current IX is obtained. Two current detection channels are used to detect the high-voltage resistor current IS and the test sample current IX, respectively. Their common terminal COM is connected to the low-voltage metal plate 6. Since the high-voltage resistor current IS returns to the low-voltage metal plate 6 through the signal detection device and does not affect the test sample current IX, the final detected test sample current IX is the current flowing through the test sample RX.

[0034] In this embodiment, the low-voltage metal plate 6 is annular in shape, with eight first mounting holes on its inner edge. The shielding washer 9 also has eight corresponding first mounting holes. Eight self-tapping screws are sequentially passed through the low-voltage metal plate 6, the shielding washer 9, and the open end of the PTFE tube 2 to achieve a fixed connection between the PTFE tube 2, the shielding washer 9, and the low-voltage metal plate 6. To reduce the influence on the magnetic field, elongated holes are provided on the low-voltage metal plate 6 to prevent short-circuit current from forming under magnetic field driving.

[0035] In this embodiment, the shielding gasket 9 has an inner shielding ring 10 and an outer shielding ring 8. The outer shielding ring 8 is in direct contact with the low-voltage metal plate 6, while the inner shielding ring 10 is grounded. The outer shielding ring 8, being in contact with the low-voltage metal plate 6, directs the leakage current IL2 generated between the booster 1 and the outer surface of the PTFE tube 2 to the low-voltage metal plate 6, preventing IL2 from flowing into the ground wire and mixing with IX. The inner shielding ring 10, not in contact with the low-voltage metal plate 6 but directly grounded, grounds the leakage current IL1 generated between the magnetic rod coil 3 and the inner surface of the PTFE tube 2, preventing IL1 from entering the low-voltage metal plate 6 and entering the ground through the IX detection circuit. The arrangement of the low-voltage metal plate 6 and the inner and outer shielding rings 8 eliminates the influence of leakage current and improves current measurement accuracy. To prevent short-circuit current from forming under magnetic field drive, both the inner shielding ring 10 and the outer shielding ring 8 have notches.

[0036] In this embodiment, the shielding washer 9 is made of a double-layer circuit board with an inner diameter of 38mm, an outer diameter of 63mm, and a thickness of 1.6mm. Each side is provided with an inner shielding ring 10 and an outer shielding ring 8. The two inner shielding rings 10 are connected by through holes, and the two outer shielding rings 8 are connected by through holes.

[0037] In this embodiment, multiple second mounting holes are opened on the outer ring edge of the low-voltage metal plate 6, and an insulating washer 7 is inserted in each second mounting hole. The low-voltage metal plate 6 and the grounding metal plate 5 are connected by bolts passing through the second mounting holes, so as to realize the mechanical connection of the low-voltage metal plate 6 and the grounding metal plate 5 through the insulating washer 7 to form electrical isolation.

[0038] In this embodiment, the high-voltage resistor 4 consists of three 300MΩ resistors connected in series and encapsulated in a plastic tube with epoxy resin. The low-voltage end of the high-voltage resistor 4 is connected to the IS input terminal of the current detection device 11, and the IX input terminal of the current detection device 11 is grounded. The common terminal COM of the two current detection devices 11 is connected to the low-voltage metal plate 6. The lower end of the plastic tube is connected to the low-voltage metal plate 6 through a shielding ring to absorb the leakage current IL3 on the surface of the plastic tube, preventing it from entering the IS detection circuit and causing errors in the IS measurement results, affecting the subsequent calculation of the sample resistance RX, and thus affecting the measurement accuracy.

[0039] In this embodiment, if the signal sampling structure of the high-voltage generator includes multiple sets of boosters 1, PTFE tubes 2 and magnetic rod coils 3, the open ends of all PTFE tubes 2 should be mounted on the same low-voltage metal plate 6 through their respective shielding washers 9.

[0040] The aforementioned current detection device 11 is a signal sampling device. By placing it at the low-voltage end, the power supply and communication isolation of the current detection device 11 are facilitated. Furthermore, by setting up an independent low-voltage metal plate 6 and a shielding gasket 9, the leakage current IL2 of the booster 1 is led to the low-voltage metal plate 6 to form a circuit with the booster body, and the leakage current IL1 of the magnetic rod coil 3 is led to the ground to prevent it from entering the IX measurement circuit. This eliminates the influence of leakage current, so that only the current IX of the test sample enters the current detection device 11. The measurement data of RX can be obtained by calculating RX = (RS*IS) / IX using the high-voltage resistor RS and IS, IX. This greatly improves the accuracy of current measurement and achieves the goal of detecting current from the low-voltage end and realizing high-precision measurement of small currents.

[0041] Through testing, when using the signal sampling structure of the high-voltage generator of this invention for measurement, the 80kV measurement resistance exceeded 50TΩ without connecting the test sample RX. In contrast, without shielding, the measured resistance was only about 300MΩ. This demonstrates that the signal sampling structure of the high-voltage generator of this invention effectively shields the influence of leakage current on the inner and outer surfaces of the PTFE tube, enabling the low-voltage end signal measurement accuracy to reach the high-voltage end measurement accuracy, while simplifying the overall structure and greatly improving safety.

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A signal sampling structure for a high-voltage generator, characterized in that, include: The PTFE tube has a voltage booster sleeved on its exterior and a magnetic rod coil installed inside. The open end of the PTFE tube is fixedly connected to a low-voltage metal plate, and a shielding gasket is installed between the two. The low-voltage metal plate is also electrically isolated from the grounding metal plate through an insulating gasket. The low-voltage end of the booster is electrically connected to the low-voltage metal plate; the high-voltage end of the booster is connected to the high-voltage resistor; the low-voltage end of the high-voltage resistor is connected to one current detection channel of the current detection device, and the input end of the other current detection channel of the current detection device is grounded; The common terminal of the two current detection channels is connected to the low-voltage metal plate.

2. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, The shielding gasket has an inner shielding ring and an outer shielding ring; the outer shielding ring is in direct contact with the low-voltage metal plate; the inner shielding ring is grounded.

3. The signal sampling structure of a high-voltage generator as described in claim 2, characterized in that, The shielding gasket is made of a double-layer circuit board, with an inner shielding ring and an outer shielding ring on each side.

4. The signal sampling structure of a high-voltage generator as described in claim 3, characterized in that, The two inner shielding rings are connected by vias; the two outer shielding rings are connected by vias.

5. The signal sampling structure of a high-voltage generator as described in claim 2, characterized in that, Both the inner and outer shielding rings have gaps.

6. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, The low-pressure metal plate is provided with elongated holes.

7. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, Multiple first mounting holes are provided on both the low-pressure metal plate and the shielding gasket; the low-pressure metal plate, the shielding gasket, and the open end of the PTFE tube are fixedly connected by screws passing through the first mounting holes.

8. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, Multiple second mounting holes are opened on the outer edge of the low-voltage metal plate; insulating washers are inserted into the second mounting holes; the low-voltage metal plate and the grounding metal plate are connected by bolts passing through the second mounting holes.

9. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, The high-voltage resistor is encapsulated in a plastic tube with epoxy resin; the low-voltage end of the plastic tube is connected to the low-voltage metal plate.

10. The signal sampling structure of a high-voltage generator as described in claim 1, characterized in that, When multiple sets of boost converters, PTFE tubes and magnetic rod coils are included, the open ends of all PTFE tubes are mounted on the same low-voltage metal plate through their respective shielding washers.

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