WO2024096224A1

WO2024096224A1 - Device for space charge measurement corresponding to cable insulation thickness parameter and space charge measurement method using same

Info

Publication number: WO2024096224A1
Application number: PCT/KR2023/007655
Authority: WO
Inventors: 박병배; 김해종; 조전욱; 김호섭; 최진욱; 권익수; 이승원
Original assignee: 한국전기연구원
Priority date: 2022-11-04
Filing date: 2023-06-02
Publication date: 2024-05-10
Also published as: KR20240064198A

Abstract

The present invention relates to a space charge measurement device for measuring a space charge distribution in a cable by a pulsed electro-acoustic (PEA) method and a space charge measurement method using same, wherein, for cables having various insulation thicknesses, the thicknesses of a piezoelectric element and an absorber of a module sensor can be changed so that it is possible to accurately and easily measure a space charge distribution in a cable.

Description

Space charge measurement device corresponding to cable insulation thickness variable and space charge measurement method using the same

The present invention relates to a space charge measurement device corresponding to a cable insulation thickness variable that measures the space charge accumulated inside a cable insulation layer using the Pulsed Electro-Acuostic Method (PEA), and a space charge measurement method using the same.

In general, the Pulsed Electro-Acuostic Method (hereinafter referred to as the “PEA method”) is applied to measure the space charge inside a dielectric in a non-destructive manner.

The PEA method enables repeated measurement of space charge on the same sample non-destructively and has excellent reproducibility. The system configuration is relatively simple, and as null is used, related research and development is being actively conducted at home and abroad.

The PEA method is configured to measure the distribution of space charge by applying a high voltage short pulse directly to the dielectric and acoustically detecting the pressure wave (or elastic wave) generated inside the dielectric using a piezoelectric element installed in the detection unit. .

As an example, Figure 1 shows a diagram showing the structure of a space charge measuring device according to the prior art.

Referring to the drawing, in the space charge measuring device according to the prior art, the position of the measurement target cable (3) is adjusted and fixed by a cable clamp (2) adjusted using a lead screw (1), and the measurement target cable ( 3) is configured so that space charge detection can be performed using the piezoelectric film (5) and organic glass sound wave absorption layer (7) provided inside the grounded metal shield box (6) while seated on the lower electrode aluminum plate (4). do.

In addition, a rectangular parallelepiped protrusion of a predetermined size is formed protruding on the upper surface of the lower electrode aluminum plate 4, and the protruding protrusion as described above is in close contact with the measurement target cable 3 and the lower electrode aluminum plate 4. Thereafter, space charge is measured using the PEA method.

Meanwhile, even for cables of the same diameter, the insulation thickness is formed differently depending on the manufacturer, so in order to analyze the characteristics of the insulation material, the thickness of the piezoelectric element and absorber must also be manufactured and installed to correspond to the cable insulation thickness.

Therefore, in the space charge measuring device according to the prior art, when measuring various cables, the piezoelectric element and absorber must be replaced and installed for each cable, but the disassembly and installation process for replacing the piezoelectric element and absorber in an actual work site is considerable. It's a hassle.

In addition, even when the replacement of the piezoelectric element and the absorber is completed through the disassembly and installation process described above, there is a problem in that accurate signal detection is not achieved if the centers of the piezoelectric element, the absorber, and the connector for signal output do not match.

The purpose of the present invention is to provide a space charge measurement device corresponding to the cable insulation thickness variable, which allows the space charge to be measured by varying the thickness of the piezoelectric element and absorber in response to cables having various insulation thicknesses depending on the manufacturer.

Another object of the present invention is to provide a plurality of module sensors to respond to the required cable insulation thickness variable, and to measure space charge by combining them in a form corresponding to the required variable through positional movement of the piezoelectric element and absorber between each module sensor. The aim is to provide a space charge measurement device corresponding to the cable insulation thickness variable that allows this to be achieved.

Another object of the present invention is to provide a method of measuring space charge corresponding to a cable insulation thickness variable using the space charge measuring device described above.

The present invention is a space charge measuring device for measuring the space charge distribution of a cable using the Pulsed Electro-Acuostic Method (PEA), which of a plurality of module sensors is used according to the insulation thickness variable of the cable to be measured. It includes a module sensor assembly in which space charge distribution is measured by matching one to the other, wherein the module sensor assembly includes a combination body in which the plurality of module sensors are accommodated and a receiving space is provided so that the plurality of module sensors are disposed at spaced apart positions, and A plurality of module sensors are provided inside the receiving space, include a piezoelectric element, an absorber, and a measuring conductor, and are configured to move up and down within the receiving space by manipulating the measuring conductor, wherein the plurality of modules The sensor is composed of different piezoelectric elements and absorbers, and the combination body includes a first moving part that provides a horizontal dividing area corresponding to the piezoelectric element, and a second moving part providing a horizontal dividing area corresponding to the absorber. And it is configured to include a third moving part that provides a horizontal division corresponding to the measuring conductor, and is characterized in that the module sensor is configured by combining the piezoelectric element, the absorber, and the measuring conductor according to the change in position of each moving part. .

The piezoelectric elements located at the top of each module sensor are formed to have different thicknesses, and each absorber located below the piezoelectric elements is also formed to have different thicknesses, so that the insulation thickness variable of the cable to be measured is It is characterized in that the piezoelectric element and the absorber are correspondingly combined according to.

The accommodation space is defined by each shell provided in the first moving part, the second moving part, and the third moving part, and the ends of each shell are connected to each other to form a vertical movement path of the measuring conductor. It is characterized by

A shell fixing conductor is further provided on the lower side of the third moving part.

The shell is formed in a cylindrical shape with a diameter corresponding to the receiving space, and a shell fixing spiral for fastening and positioning the shell fixing conductor is formed on the lower part of the receiving space and a portion of the outer peripheral surface of the shell fixing conductor, and the shell A measuring spiral for fastening and positioning the measuring conductor is formed on the inner peripheral surface of the fastening hole provided in the fixed conductor and a portion of the outer peripheral surface of the measuring conductor.

The shell includes a first shell that corresponds to the first moving part and moves together with the first moving part, a second shell that corresponds to the second moving part and moves together with the second moving part, and an interior of the third moving part. It includes a third shell accommodated in, and when the first moving part and the first shell move, the piezoelectric element is accommodated inside the first shell, and the absorber is accommodated inside the second shell. The conductor maintains the first position to move the position of the piezoelectric element, and when the second moving part and the second shell move, the measuring conductor moves inside the third shell to maintain the second position. It is characterized in that the position of the absorber is moved.

The combination body is formed by stacking the first moving part, the second moving part, and the third moving part in a cylindrical shape with corresponding planes, and each moving part individually rotates around a main axis passing through the central part. It is characterized in that it is configured to make it possible.

A sensor cover is further provided at least on the upper side of the first moving part, and the sensor cover is characterized in that a measuring hole is provided at a position corresponding to the top of each module sensor.

In another aspect, the method of measuring the space charge corresponding to the cable insulation thickness variable using a space charge measurement device corresponding to the cable insulation thickness variable having the above characteristics includes an insulation thickness confirmation step of checking the insulation thickness variable of the cable to be measured, and the insulation thickness A piezoelectric element arrangement step in which one piezoelectric element is arranged for measurement of the measurement target cable by moving the first moving part to correspond to the insulation thickness variable confirmed through the confirmation step, and the piezoelectric element arrangement step is arranged through the piezoelectric element arrangement step. An absorber arrangement step in which one absorber is disposed for measurement of the cable to be measured by moving the second moving part to the lower side of the piezoelectric element, and the first absorber corresponding to the position in a state in which the arrangement of the piezoelectric element and the absorber is completed. 3 By manipulating the measuring conductor of the moving part, the piezoelectric element, the absorber, and the measuring conductor are aligned in the correct position and the module sensor combined with the cable to be measured is fixed so that it adheres more closely to the cable through the module sensor application step and the module sensor application step. It is characterized by including a space charge measurement step in which the space charge distribution of the cable to be measured is measured through the Pulsed Electro-Acuostic Method (PEA) using a fixed module sensor.

The module sensor assembly constituting the present invention is configured so that a plurality of piezoelectric elements and an absorption layer can move positions.

Therefore, even when measuring cables with various insulation thicknesses, the space charge can be measured after moving the provided piezoelectric element and absorption layer to correspond to the insulation thickness of the cable to be measured without disassembling and installing the piezoelectric element and absorption layer. there is.

In addition, the piezoelectric element and the absorption layer whose positions are moved as described above are guided in their moving positions within the combination body that provides a moving space, and are positioned at the center during the setting process for measurement by the shell fixing conductor and measuring conductor that are moved up and down after the positioning. As alignment is achieved, more accurate space charge measurements can be made.

In addition, the piezoelectric element and the absorption layer are each separated and movable, so various combinations can be formed, which has the advantage of being able to measure space charge by easily responding to a wider variety of cable insulation thickness variables. have

1 is a diagram showing the structure of a space charge measuring device according to the prior art.

Figure 2 is a diagram showing an example of a space charge measuring device corresponding to a cable insulation thickness variable according to the present invention.

Figure 3 is a cross-sectional view taken along section A-A of Figure 2.

Figure 4 is a diagram for explaining the detailed structure of the module sensor, which is the main component of the present invention.

Figure 5 is a diagram showing the settings when measuring each module sensor corresponding to the cable insulation thickness.

Hereinafter, some embodiments of the present invention will be described in detail through illustrative drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing embodiments of the present invention, if detailed descriptions of related known configurations or functions are judged to impede understanding of the embodiments of the present invention, the detailed descriptions will be omitted.

Additionally, when describing the components of an embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component can be connected or connected directly to that other component, but there is no need for another component between each component. It should be understood that may be “connected,” “combined,” or “connected.”

The space charge measurement device corresponding to the cable insulation thickness variable (hereinafter referred to as “space charge measurement device”) according to the present invention is based on the PEA method to enable measurement by combining signal detection units to correspond to the insulation thickness of the cable to be measured. It is composed.

FIG. 2 is a diagram showing an example of a space charge measuring device corresponding to a cable insulation thickness variable according to the present invention, and FIG. 3 is a cross-sectional view taken along the line A-A of FIG. 2. In addition, Figure 4 shows a drawing to explain the detailed structure of the module sensor, which is the main component of the present invention, and Figure 5 shows a drawing showing the settings of each module sensor corresponding to the cable insulation thickness when measuring.

Meanwhile, although not shown in the drawing, in this embodiment, the space charge measuring device can fix the cable in a way that the pressing force is adjusted by moving the cable clamp in position by a lead screw.

In this embodiment, the module sensor assembly 100, in which space charge is measured by being in close contact with the cable by the cable clamp, is configured to include a plurality of module sensors 400. Therefore, space charge can be easily measured through the application of the module sensor 400 corresponding to various cable insulation thickness variables.

In detail, the module sensor assembly 100 includes a plurality of module sensors 400 each including a piezoelectric element 420, an absorber 440, and a measurement conductor 460, and the plurality of module sensors 400 are spaced apart from each other. It is configured to include a combination body 200 in which a receiving space is provided to be placed in a given position.

The module sensor 400 is configured for measurement based on the above-described PEA method, in which the piezoelectric element 420 is located at the uppermost side, and the absorber 440 and the measurement conductor 460 are simply stacked sequentially below it. It has a structured structure.

In this embodiment, the piezoelectric element 420 may be made of polyvinylidene fluoride (PVDF), which has excellent frequency characteristics, and each piezoelectric element 420 constituting the plurality of module sensors 400 can be connected to various cables. They are formed differently to correspond to the insulation thickness variable.

That is, the piezoelectric elements 420 may be formed to have different thicknesses or sizes, and in this embodiment, each has a different thickness as the accommodation space provided in the combination body 200 is formed to a limited size.

The absorber 440 is intended to prevent vibrations other than acoustic waves generated from the cable to be measured from being transmitted to the piezoelectric element 420, and may be made of polymethylmethacrylate (PMMA), and may be formed of a plurality of modules. Each absorber 440 constituting the sensor 400 is also provided to have different thicknesses like the piezoelectric element 420.

In addition, the measuring conductor 460 is for detecting a signal transmitted from the piezoelectric element 420, and is configured to move upward and downward from the lower side of the absorber 440 toward the piezoelectric element 420.

That is, the measurement conductor 460 raises the absorber 440 and the piezoelectric element 420 for measurement so that the measurement target cable and the module sensor 400 can be maintained in close contact.

In addition, the measuring conductor 460 is disposed at a plurality of set positions when lowered, allowing the piezoelectric element 420 and the absorber 440 to be replaced.

In detail, the module sensor 400 can be combined with the piezoelectric element 420 and the absorber 440 by moving its position while being spaced at a certain interval in the receiving space provided in the combination body 200, as described above. there is.

For the above combination, the module sensor assembly 100 can be combined while moving along a certain path by dividing the space in which the piezoelectric element 420, the absorber 440, and the measuring conductor 460 are accommodated, respectively, in the horizontal direction. there is.

In this embodiment, the module sensor assembly 100 is configured to be rotatably movable for the above combination.

In detail, the combination body 200 in which the module sensor 400 is accommodated is configured in a form in which a plurality of horizontally divided moving parts are stacked to enable rotational movement for each layer based on the main axis 210.

The plurality of moving parts include a first moving part 240 providing a horizontal dividing area corresponding to the piezoelectric element 420, a second moving part 260 providing a horizontal dividing area corresponding to the absorber 440, and It includes a third moving part 280 that provides a horizontal division area corresponding to the measurement conductor 460.

In addition, a sensor cover 229 is further provided on the upper side of the first moving part 240, and a measurement hole is further provided in the sensor cover 220 at a position corresponding to the top of each module sensor 400. , the sensor cover 229 may also be provided on the second moving part 260 and the third moving part 280.

In addition, a housing 110 that can distribute and support the cable load while guiding the rotation path may be further provided on one side of the combination body 200.

In addition, the accommodation space provided in the combination body 200 is defined by the rotating shell 410 provided in the first moving part 240, the second moving part 260, and the third moving part 280. .

That is, the rotating shell 410 is formed in a cylindrical shape with a diameter corresponding to the receiving space and has first to third shells (412, 414, 416) corresponding to the first to third moving parts (240, 260, 280). ), and the ends of each shell are connected to each other to form a vertical movement path of the measuring conductor 460.

In addition, a shell fixing conductor 480 is further provided on the lower side of the third moving part 280 so that the shells adjacent to each other can maintain a fixed position, and the measuring conductor 460 is included in the shell fixing conductor 480. A portion of may be accepted.

For this purpose, a shell fixing helix 482 is formed in the lower part of the receiving space and a portion of the outer peripheral surface of the shell fixing conductor 480 for fastening and positioning the shell fixing conductor 480, and the shell fixing conductor 480 A fastening hole (not given a reference numeral) is provided in the central portion of , which has a diameter corresponding to a portion of the measuring conductor 460 to be accommodated.

In addition, a measuring spiral 462 is formed on the inside of the fastening hole and a portion of the outer peripheral surface of the measuring conductor 460 for fastening and positioning the measuring conductor 460, so that it rises or falls depending on the rotation direction of the measuring conductor 460. Position adjustments may be made.

Meanwhile, the first shell 412 corresponding to the first moving part 240 can be moved together with the first moving part 240 with the piezoelectric element 420 accommodated therein, and the second shell (414) can be moved together with the second moving part (260) while receiving the absorber (440). Additionally, the third shell 416 is accommodated inside the third moving part 280 and provides a path for the measuring conductor 460 to move up and down.

In other words, the space charge measuring device according to the present invention can combine the module sensor 400 by rotating each moving part in response to the insulation thickness variable of the cable to be measured, thereby measuring various cables more accurately and easily. You can.

Hereinafter, a method of measuring cable space charge using the space charge measuring device configured as above will be described.

As described above, the space charge measuring device according to the present invention measures space charge distribution using the PEA method, and the piezoelectric element 420 and the absorber 440 must correspond to the insulation thickness variable of the cable to be measured for measurement accuracy. It can be improved.

Therefore, in order to measure the space charge distribution of a cable using the space charge measuring device according to the present invention, an insulation thickness confirmation step is first performed to check the insulation thickness variable of the cable to be measured.

The insulation thickness of the cable to be measured can be confirmed in the cable purchase specifications, and for more accurate measurement, you can cut a portion of the cable and check the cross-sectional shape to check the thickness of the insulation layer.

Meanwhile, after confirming the insulation thickness variable of the cable to be measured as described above, the first moving part 240 is moved to correspond to the confirmed insulation thickness variable so that any one piezoelectric element 420 is used to measure the cable to be measured. The piezoelectric element placement step is performed.

In other words, the piezoelectric element arrangement step is a process of arranging the piezoelectric element 420 that matches the measurement of the insulation thickness variable confirmed by the cable measurement position. After adjusting the position of the measurement conductor 460, the first moving unit 240 rotation takes place.

In detail, in order to move the piezoelectric element 420 provided inside the first shell 412, the measuring conductor 460 is moved so that the piezoelectric element 420 is located in the first shell 412, The measuring conductor 460 is moved to the first position so that the absorber 440 is located in the second shell 414.

When the measuring conductor 460 moves to the first position and maintains the moving position, the first moving part 240 rotates around the main axis 220, which changes the position of the piezoelectric element 420. As is varied, the piezoelectric element 420 corresponding to the insulation thickness variable of the cable to be measured is placed at the measurement position, and the piezoelectric element placement step is completed.

After the piezoelectric element placement step is completed as described above, an absorber placement step is performed to re-adjust the measurement conductor 460 and place the absorber 440 at the measurement position.

To this end, in the absorber arrangement step, first, after the piezoelectric element arrangement step, the second moving part 260 is moved from the first moving part 240 so that only the absorber 440 is provided inside the second shell 414. The piezoelectric element 420 is maintained positioned inside the first shell 412 by rotating it at a predetermined angle.

Then, in the above state, the measuring conductor 460 is moved downward to move the measuring conductor 460 to the second position inside the third shell 416, and then the second moving part 260 is rotated again. The absorber placement step is completed by placing the absorber 440 corresponding to the insulation thickness variable of the cable to be measured at the measurement position.

Meanwhile, when the absorber arrangement step is completed as described above, the module sensor application step is performed in which the piezoelectric element 420 and the absorber 440 disposed at the measurement position are combined.

In the module sensor application step, the piezoelectric element 420 and the absorber 440 arranged through each step described above are aligned in the correct position by moving the measuring conductor 460 inside the third shell 416 corresponding to the corresponding position upward. This comes true.

That is, the first shell 412, the second shell 414, and the third shell 416, which are arranged at a predetermined angle, can be aligned in the correct position while moving the measurement conductor 460 upward, and when necessary, The position alignment process can be performed while rotating the first moving part 240 and the second moving part 260 by a predetermined angle.

In addition, the module sensor 400, which is combined to correspond to the insulation thickness variable of the cable to be measured through the position alignment process as described above, can be brought into closer contact with the cable to be measured by the upward movement of the measurement conductor 460.

Meanwhile, when the module sensor 400 combined as described above is closely fixed to the cable to be measured, the space charge distribution of the cable to be measured is measured through the Pulsed Electro-Acuostic Method (PEA) as described above. A space charge measurement step is performed.

And, as shown in FIG. 5, each module sensor 400 is composed of different piezoelectric elements 420 and absorbers 440, and the piezoelectric elements 420 and absorbers 440 are adjusted to correspond to various cable insulation thickness variables. Since selective application can be easily made, easier and more accurate measurement can be made when measuring space charge.

What has been described above is only an example for carrying out the space charge measuring device according to the present invention, and the present invention is not limited to the above-described embodiment, and does not depart from the gist of the present invention as claimed in the claims below. Anyone with ordinary knowledge in the technical field to which the invention pertains will say that the technical spirit of the present invention exists to the extent that it can be implemented with various modifications.

The present invention is a technology that can determine whether there is an abnormality in the conductor of electrical and electronic system wiring that requires a high level of stability in preparation for the increase in wire fires and electrical equipment accidents every year. It diagnoses the condition of the cable in a non-destructive way to improve reliability and reliability. It has the advantage of being applicable to various industrial fields in that it increases stability and allows economical maintenance.

In addition, the global market for control and measuring devices required for network control and monitoring is expected to continue to expand due to the expansion of power generation and transmission and distribution network facilities due to the increase in electricity demand in emerging countries, and the cable safety diagnosis market to prevent accidents such as fire and power equipment failure is expected to grow. As it is expected to expand, the industrial applicability of the present invention is expected to increase.

Claims

In the space charge measurement device for measuring the space charge distribution of a cable using the Pulsed Electro-Acuostic Method (PEA),

It includes a module sensor assembly in which space charge distribution is measured by matching one of a plurality of module sensors according to the insulation thickness variable of the cable to be measured,

The module sensor assembly is,

A combination body in which the plurality of module sensors are accommodated, and a receiving space is provided so that the plurality of module sensors are disposed at positions spaced apart from each other;

A plurality of module sensors are provided inside the receiving space, include a piezoelectric element, an absorber, and a measuring conductor, and are configured to move up and down within the receiving space by manipulating the measuring conductor.

The plurality of module sensors are each composed of different piezoelectric elements and absorbers,

The combination body includes a first moving part providing a horizontal dividing area corresponding to the piezoelectric element, a second moving part providing a horizontal dividing area corresponding to the absorber, and a horizontal dividing area corresponding to the measuring conductor. A space charge measuring device corresponding to a cable insulation thickness variable, characterized in that it is configured to include a third moving part, and a module sensor is configured by combining the piezoelectric element, an absorber, and a measuring conductor according to a change in the position of each moving part.
According to claim 1,

The piezoelectric elements located at the top of each module sensor are formed to have different thicknesses, and each absorber located below the piezoelectric elements is also formed to have different thicknesses, so that the insulation thickness variable of the cable to be measured is A space charge measurement device corresponding to a cable insulation thickness variable, characterized in that the piezoelectric element and the absorber are respectively combined according to.
According to claim 1,

The accommodation space is defined by each shell provided in the first moving part, the second moving part, and the third moving part,

A space charge measurement device corresponding to a cable insulation thickness variable, characterized in that the ends of each shell are connected to each other to form a vertical movement path of the measurement conductor.
According to clause 3,

A space charge measuring device corresponding to a cable insulation thickness variable, characterized in that a shell-fixed conductor is further provided on the lower side of the third moving part.
According to clause 4,

The shell is formed in a cylindrical shape with a diameter corresponding to the receiving space,

A shell fixing spiral for fastening and positioning the shell fixing conductor is formed in the lower part of the receiving space and a portion of the outer peripheral surface of the shell fixing conductor,

A space charge measuring device corresponding to a cable insulation thickness variable, characterized in that a measuring spiral for fastening and positioning the measuring conductor is formed on the inner peripheral surface of the fastening hole provided in the shell fixing conductor and a portion of the outer peripheral surface of the measuring conductor.
According to clause 3,

The shell corresponds to the first moving part and moves together with the first moving part,

A second shell corresponding to the second moving part and moving together with the second moving part, and

It includes a third shell accommodated inside the third moving part,

When the first moving part and the first shell are moved, the piezoelectric element is accommodated inside the first shell, and the measuring conductor maintains the first position so that the absorber is accommodated inside the second shell, so that the piezoelectric The position of the element is moved,

When the second moving part and the second shell are moved, the measuring conductor moves inside the third shell and maintains the second position, so that the position of the absorber is moved. Space charge corresponding to the cable insulation thickness variable Measuring device.
According to claim 1,

The combination body is formed by stacking the first moving part, the second moving part, and the third moving part in a cylindrical shape with corresponding planes, and each moving part individually rotates around a main axis passing through the central part. A space charge measurement device corresponding to a cable insulation thickness variable, characterized in that it is configured to enable.
According to claim 1,

A sensor cover is further provided at least on the upper side of the first moving part,

A space charge measurement device corresponding to a cable insulation thickness variable, characterized in that the sensor cover has a measurement hole at a position corresponding to the top of each module sensor.
Using a space charge measuring device corresponding to the cable insulation thickness variable according to any one of claims 1 to 8,

Insulation thickness confirmation step of checking the insulation thickness variable of the cable to be measured;

A piezoelectric element arrangement step in which one piezoelectric element is arranged to measure the cable to be measured by moving the first moving part to correspond to the insulation thickness variable confirmed through the insulation thickness confirmation step;

An absorber arrangement step of moving the second moving part below the piezoelectric element disposed through the piezoelectric element arrangement step to dispose an absorber for measuring the measurement target cable;

When the arrangement of the piezoelectric element and the absorber is completed, the measurement conductor of the third moving part corresponding to the corresponding position is manipulated so that the piezoelectric element, the absorber, and the measurement conductor are aligned in the correct position, and the module sensor combined with the cable to be measured is brought into closer contact. A module sensor application step of fixing as much as possible; and

A space charge measurement step in which the space charge distribution of the cable to be measured is measured through the Pulsed Electro-Acuostic Method (PEA) using a module sensor fixed to the cable through the module sensor application step; includes; Space charge measurement method for cable insulation thickness variables.