CN118362794A - Kelvin electrostatic probe-based basin-type insulator surface charge surge online measurement method - Google Patents

Abstract

The present invention discloses an online measurement method for the surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe, and the online measurement method for the surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe comprises the following steps: setting a Kelvin electrostatic probe, so that the Kelvin electrostatic probe faces the pouring port of the pot-type insulator and the Kelvin electrostatic probe is separated from the pot-type insulator; and inferring the surface charge change of the pot-type insulator by detecting the change amount and change rate of the surface potential of the pot-type insulator at the pouring port by the Kelvin electrostatic probe. The online measurement method for the surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention can realize non-contact online measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

Description

Online measurement method of surface charge surge of pot-type insulator based on Kelvin electrostatic probe

Technical Field

The invention relates to the technical field of electrical engineering, and in particular to an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe.

Background technique

The electrostatic probe method is a widely used method for measuring the surface charge of insulators in gas insulated transmission lines (GIL).

The electrostatic probe method is a method that uses electrostatic induction to measure the surface charge distribution of insulators. Electrostatic probes are divided into capacitive electrostatic probes and Kelvin electrostatic probes. Capacitive electrostatic probes are passive probes. They generate induced potential on the probe based on electrostatic induction, and calculate the surface charge density by combining the principle of capacitive voltage division. This method can quantitatively measure the surface charge of insulators, but the attenuation characteristics of the induced potential seriously restrict the accuracy of its measurement. Kelvin electrostatic probes are active probes. The induction electrode in the probe keeps oscillating while gradually changing the voltage on the probe. If the probe is at a certain voltage, the induced current of the probe is always zero and does not change with the oscillation of the probe, then the probe voltage at this time is equal to the voltage of the measured surface. The Kelvin probe method adjusts the voltage of the probe based on the induced current, has high accuracy, and is a relatively ideal measurement method for surface charge.

In the related art, the surface charge measurement method of the basin insulator using the Kelvin electrostatic probe, in order to achieve the charge measurement of the entire insulator surface, drives the electrostatic probe to scan point by point along the insulator surface through the motion drive system. In order to avoid the influence of the motion control system on the original electric field of the gas-insulated transmission line, it is necessary to add a shielding chamber and other structures. The use of the shielding chamber will inevitably change the original pipeline structure of the gas-insulated transmission line, which not only increases the cost, but also is not suitable for online measurement.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe, which can realize non-contact online measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

The invention also proposes an online measurement structure for surface charge surge of a basin-type insulator based on a Kelvin electrostatic probe.

To achieve the above-mentioned purpose, according to an embodiment of the first aspect of the present invention, an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe is proposed. The online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe comprises: setting a Kelvin electrostatic probe so that the Kelvin electrostatic probe faces a casting port of a pot-type insulator and the Kelvin electrostatic probe is separated from the pot-type insulator; detecting the change amount and change rate of the surface potential of the pot-type insulator at the casting port by the Kelvin electrostatic probe; characterizing the surface charge surge phenomenon of the pot-type insulator according to the change amount and change rate of the surface potential of the pot-type insulator at the casting port detected by the Kelvin electrostatic probe.

The on-line measurement method for surface charge surge of pot-type insulators based on Kelvin electrostatic probe according to the embodiment of the present invention can realize non-contact on-line measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

In addition, the on-line measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to the above embodiment of the present invention may also have the following additional technical features:

According to an embodiment of the present invention, the axial direction of the Kelvin electrostatic probe is oriented along the normal direction of the circumferential surface of the pot insulator.

According to one embodiment of the present invention, the Kelvin electrostatic probe is coaxially arranged with the pouring port.

According to an embodiment of the present invention, the Kelvin electrostatic probe is spaced 2-5 mm from the pot-type insulator.

According to an embodiment of the present invention, the pot-type insulator is filled with epoxy resin.

According to an embodiment of the second aspect of the present invention, an online measurement structure for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe is proposed, and the online measurement structure for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe comprises: a pot-type insulator, wherein a pouring port is provided on the pot-type insulator; a Kelvin electrostatic probe, wherein the Kelvin electrostatic probe faces the pouring port and is spaced apart from the pot-type insulator so that the Kelvin electrostatic probe is suitable for detecting the amount and rate of change of the surface potential of the pot-type insulator at the pouring port; and a processing module, wherein the processing module is suitable for characterizing the surface charge surge phenomenon of the pot-type insulator according to the amount and rate of change of the surface potential of the pot-type insulator at the pouring port detected by the Kelvin electrostatic probe.

The on-line measurement structure for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention can realize non-contact on-line measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

According to an embodiment of the present invention, the Kelvin electrostatic probe is oriented along the radial direction of the pot-type insulator.

According to one embodiment of the present invention, the Kelvin electrostatic probe is coaxially arranged with the pouring port.

According to an embodiment of the present invention, the Kelvin electrostatic probe is spaced 2-5 mm from the pot-type insulator.

According to an embodiment of the present invention, the pot-type insulator is filled with epoxy resin.

Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

FIG1 is a schematic structural diagram of an online measurement structure for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of the structure of the online measurement structure of the surface charge of the post insulator.

FIG3 is a schematic diagram showing the variation of the insulator surface potential over time in the online measurement structure for the post insulator surface charge.

4 is a schematic diagram of the surface potential distribution of an insulator under different charge surge conditions according to an online measurement structure for surface charge surge of a basin-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention.

5 is a flow chart of an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention.

Figure numerals: online measurement structure 1 for surface charge surge of pot-type insulator based on Kelvin electrostatic probe, pot-type insulator 10, casting mouth 11, epoxy resin 12, flange 13, mounting hole 14, electrode 15, Kelvin electrostatic probe 20, online measurement structure 2 for surface charge of post insulator, post insulator 30, corona needle 40, grounding plate electrode 50.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

The following describes an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention with reference to the accompanying drawings.

As shown in FIG. 1 and FIG. 5 , the online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention comprises the following steps:

The Kelvin electrostatic probe 20 is disposed so that the Kelvin electrostatic probe 20 faces the pouring port 11 of the pot-type insulator 10 and the Kelvin electrostatic probe 20 is spaced apart from the pot-type insulator 10 .

The change amount and change rate of the surface potential of the pot insulator 10 at the pouring port 11 are detected by the Kelvin electrostatic probe 20 .

The charge surge phenomenon on the surface of the pot-type insulator 10 is characterized according to the change amount and change rate of the surface potential of the pot-type insulator 10 at the pouring port 11 detected by the Kelvin electrostatic probe 20 .

Specifically, when the charge in the local area of the surface of the pot insulator 10 increases sharply, based on the law of potential superposition, the surface potential of the pot insulator 10 at the pouring port 11 will inevitably change. By detecting the change amount and change rate of the surface potential of the pot insulator 10 at the pouring port 11 with the Kelvin electrostatic probe 20, the charge surge phenomenon on the surface of the pot insulator 10 can be inferred.

In order to further verify the feasibility of this method, as shown in Figures 2 and 3, a post insulator 30 is used to construct an online measurement structure 2 for the surface charge of a post insulator. The post insulator 30 is cylindrical, with a diameter d of 80 mm and a height h of 60 mm, and is made of alumina epoxy resin. The bottom surface of the post insulator 30 is in close contact with the grounding plate electrode 50 (the up and down directions are shown by the arrows in the figure), and the corona needle 40 is arranged in the middle of the height direction of the post insulator 30. In addition, the Kelvin electrostatic probe 20 is vertically installed at the center of the top surface of the post insulator 30. The corona needle 40 is used to discharge and quickly accumulate surface charges. The change of the surface potential of the insulator collected by the Kelvin electrostatic probe 20 over time is shown in Figure 3.

As shown in Figure 3, during the voltage boost stage, the surface potential increases rapidly with the applied voltage. During the corona discharge stage, as the surface charge accumulates rapidly, the surface potential gradually increases. Once the applied voltage is disconnected, the surface potential decreases rapidly. After the applied voltage is grounded, the surface potential decreases slowly. This shows that the surface potential of the insulator changes with the change of the surface charge of the insulator.

Therefore, in the online measurement method of the surface charge surge of the pot-type insulator based on the Kelvin electrostatic probe, the surface charge surge phenomenon of the pot-type insulator 10 can be effectively characterized by measuring the change of the insulator surface potential of the casting port 11 of the pot-type insulator 10 over time.

According to the on-line measurement method of the surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe in an embodiment of the present invention, by setting the Kelvin electrostatic probe 20, the Kelvin electrostatic probe 20 is directed toward the casting port 11 of the pot-type insulator 10 and the Kelvin electrostatic probe 20 is spaced apart from the pot-type insulator 10, and the Kelvin electrostatic probe 20 can be used to detect the change amount and change rate of the surface potential of the pot-type insulator 10 at the casting port 11 to characterize the surface charge surge phenomenon of the pot-type insulator 10, and because the Kelvin electrostatic probe 20 is spaced apart from the pot-type insulator 10, the Kelvin electrostatic probe 20 will not contact the surface of the pot-type insulator 10, will not affect the surface charge distribution of the pot-type insulator 10, the detection accuracy is high, there is no need to destroy the original structure of the pot-type insulator 10, and the setting cost is low.

Furthermore, since the Kelvin electrostatic probe 20 detects the change in the surface potential of the basin-type insulator 10 at the pouring mouth 11, compared with the technical solution in the related art that uses a motion drive system to drive the probe to scan the insulator surface point by point, the Kelvin electrostatic probe 20 does not need to move, and there is no need to set up an additional drive system. This not only saves the need for setting up a drive system and reducing costs, but also avoids the influence of the drive system on the original electric field of the gas-insulated transmission line. There is no need to set up additional structures such as a shielding chamber, which can further reduce costs and facilitate online measurement of the charge surge of the basin-type insulator 10.

Further, FIG4 shows the surface potential distribution measured by the Kelvin electrostatic probe 20 under the condition of surface charge surge in different areas of the surface of the pot-type insulator 10. When the surface charge surge area is far away from the pouring port 11, the surface potential changes slowly, with a rate of change of only 0.5 V/s. When the surface charge surge area is close to the pouring port 11, the surface potential increases rapidly to -1200 V, with a rate of change of 40 V/s. Therefore, the surface charge surge phenomenon of the pot-type insulator 10 can be characterized by judging the change in the surface potential at the pouring port 11 of the pot-type insulator 10, which is convenient for online measurement of the surface charge surge of the pot-type insulator.

Therefore, the online measurement method of the surface charge surge of a pot-type insulator based on the Kelvin electrostatic probe according to the embodiment of the present invention can realize non-contact online measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

The following describes an online measurement method for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to a specific embodiment of the present invention with reference to the accompanying drawings.

Advantageously, as shown in Fig. 1, the axial direction of the Kelvin electrostatic probe 20 is oriented along the normal direction of the circumferential surface of the pot-type insulator. In this way, the Kelvin electrostatic probe 20 can be perpendicular to the tangent direction of the surface of the pot-type insulator 10 at the pouring port 11, thereby improving the accuracy of the detection of the Kelvin electrostatic probe 20.

More advantageously, as shown in Fig. 1, the Kelvin electrostatic probe 20 is coaxially arranged with the pouring port 11. This can further improve the accuracy of the detection by the Kelvin electrostatic probe 20.

Optionally, the Kelvin electrostatic probe 20 is spaced 2-5 mm from the pot-type insulator 10 . Here, 3 mm is preferred. This ensures that the accuracy of the Kelvin electrostatic probe 20 detection is ensured while ensuring that the Kelvin electrostatic probe 20 does not contact the pot-type insulator 10 .

Specifically, as shown in FIG1 , the pot insulator 10 is filled with epoxy resin 12. Specifically, an electrode 15 is embedded in the epoxy resin 12. The epoxy resin 12 is also filled in the pouring port 11. The edge of the pot insulator 10 has a flange 13, and the flange 13 is provided with a mounting hole 14. This makes it easy to ensure the performance of the pot insulator 10.

The following describes, with reference to FIG. 1 , an online measurement structure 1 for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention.

The on-line measurement structure 1 for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention includes a pot-type insulator 10 and a Kelvin electrostatic probe 20 .

The pot insulator 10 is provided with a pouring port 11. The Kelvin electrostatic probe 20 is disposed toward the pouring port 11 and spaced apart from the pot insulator 10 so that the Kelvin electrostatic probe 20 is suitable for detecting the amount and rate of change of the surface potential of the pot insulator 10 at the pouring port 11. The processing module is suitable for characterizing the surface charge surge phenomenon of the pot insulator 10 according to the amount and rate of change of the surface potential of the pot insulator 10 at the pouring port 11 detected by the Kelvin electrostatic probe 20.

The on-line measurement structure 1 for surface charge surge of a pot-type insulator based on a Kelvin electrostatic probe according to an embodiment of the present invention can realize non-contact on-line measurement without changing the original structure of the pot-type insulator, and has the advantages of high accuracy and low cost.

Advantageously, as shown in Fig. 1, the axial direction of the Kelvin electrostatic probe 20 is oriented along the normal direction of the circumferential surface of the pot-type insulator. In this way, the Kelvin electrostatic probe 20 can be perpendicular to the tangent direction of the surface of the pot-type insulator 10 at the pouring port 11, thereby improving the accuracy of the detection of the Kelvin electrostatic probe 20.

More advantageously, as shown in Fig. 1, the Kelvin electrostatic probe 20 is coaxially arranged with the pouring port 11. This can further improve the accuracy of the detection by the Kelvin electrostatic probe 20.

Optionally, the Kelvin electrostatic probe 20 is spaced 2-5 mm from the pot-type insulator 10 . Here, 3 mm is preferred. This ensures that the accuracy of the Kelvin electrostatic probe 20 detection is ensured while ensuring that the Kelvin electrostatic probe 20 does not contact the pot-type insulator 10 .

Specifically, as shown in FIG1 , the pot insulator 10 is filled with epoxy resin 12. Specifically, an electrode 15 is embedded in the epoxy resin 12. The epoxy resin 12 is also filled in the pouring port 11. The edge of the pot insulator 10 has a flange 13, and the flange 13 is provided with a mounting hole 14. This makes it easy to ensure the performance of the pot insulator 10.

Other structures and operations of the on-line measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims (10)

1. An online measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe, characterized in that it comprises the following steps: Disposing a Kelvin electrostatic probe, so that the Kelvin electrostatic probe faces a pouring port of a pot-type insulator and the Kelvin electrostatic probe is spaced apart from the pot-type insulator; Detecting the change amount and change rate of the surface potential of the basin insulator at the pouring port by the Kelvin electrostatic probe; The charge surge phenomenon on the surface of the pot insulator is characterized according to the change amount and change rate of the surface potential of the pot insulator at the pouring port detected by the Kelvin electrostatic probe. 2. The online measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 1 is characterized in that the axial direction of the Kelvin electrostatic probe is oriented along the normal direction of the circumferential surface of the pot-type insulator. 3. The online measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 1 is characterized in that the Kelvin electrostatic probe is coaxially arranged with the pouring port. 4. The online measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 1, characterized in that the Kelvin electrostatic probe is spaced 2-5 mm from the pot-type insulator. 5. The on-line measurement method for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 1, characterized in that the pot-type insulator is filled with epoxy resin. 6. An online measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe, characterized by comprising: A pot-type insulator, wherein a pouring port is provided on the pot-type insulator; A Kelvin electrostatic probe, the Kelvin electrostatic probe is disposed toward the pouring port and spaced apart from the pot-type insulator so that the Kelvin electrostatic probe is suitable for detecting a change amount and a change rate of a surface potential of the pot-type insulator at the pouring port; A processing module is adapted to characterize the surface charge surge phenomenon of the pot insulator according to the change amount and change rate of the surface potential of the pot insulator at the pouring port detected by the Kelvin electrostatic probe. 7. The on-line measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 6, characterized in that the Kelvin electrostatic probe is oriented along the radial direction of the pot-type insulator. 8. The on-line measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 6, characterized in that the Kelvin electrostatic probe is coaxially arranged with the pouring port. 9. The on-line measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 6, characterized in that the Kelvin electrostatic probe is spaced 2-5 mm from the pot-type insulator. 10 . The on-line measurement structure for surface charge surge of pot-type insulator based on Kelvin electrostatic probe according to claim 6 , characterized in that the pot-type insulator is filled with epoxy resin.