Three-probe anti-interference single-phase displacement current method and structure

Abstract

The invention discloses a three-probe anti-interference single-phase displacement current method and structure, and relates to the technical field of voltage sensors and measurement, and the method comprises the steps: carrying out the internal and external copper pasting of three regions, and enabling the three-probe anti-interference single-phase displacement current and a power line to form an equivalent circuit; converting the displacement current into a conducting current through a converter; a full-rank equation set is obtained by using a coupling structure of the three probes and a differential coupling capacitance formed by a line. A displacement current between conductors is converted into a conducting current by adopting a single-phase displacement current method. Through a three-probe coupling mechanism, an impedance value between two layers of copper foils is changed, and response values of the device under different resistance values of the two copper foils are obtained. The non-intrusive measurement method of the displacement current method is equivalent to short circuit of the two layers of copper sheets and measurement of the short-circuit current of the copper sheets. The differential coupling capacitance is formed through the coupling structure of the three probes and the line, and a full-rank equation set is obtained, so that the interference to the ground capacitance CX is eliminated, and the anti-interference performance of the displacement current method is realized.

Description

Technical Field

[0001] The invention relates to the field of voltage sensors and measurement technology, in particular to a three-probe anti-interference single-phase displacement current method and system. Background Art

[0002] Traditional electromagnetic voltage measurement devices are difficult to meet the conditions of large-scale application due to their large size, high cost, and difficulty in installation. In actual power systems, there are many live conductors (such as metal structures such as towers, switch cabinets, and the ground around the conductors), and the voltage coupling mechanism will form a complex distributed capacitance coupling structure with them, which leads to a complex electric field distribution around the measured conductor. The displacement current flowing into the measurement system is the superposition of the displacement currents formed by the voltages of various field sources in the environment; on the other hand, the hardware circuit inside the sensor contains a large number of resistors, capacitors, inductors and other components, especially capacitors and inductors, which often have stray electric fields and stray magnetic fields, which will further interfere with the electric field distribution signal received by the voltage coupling mechanism of the sensor on the electric field distribution around the two types of power lines. Summary of the invention

[0003] In view of the above-mentioned problems, the present invention is proposed.

[0004] Therefore, the technical problem solved by the present invention is: how to solve the problem of complex electric field distribution around the conductor to be measured.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a three-probe anti-interference single-phase displacement current method, comprising: copper pasting inside and outside three areas so that the three-probe anti-interference single-phase displacement current and the power line form an equivalent circuit; the displacement current is converted into a conduction current through a converter; and the coupling structure of the three probes is used to form a different coupling capacitance with the line to obtain a full-rank equation group.

[0006] As a preferred scheme of the three-probe anti-interference single-phase displacement current method described in the present invention, the equivalent circuit includes the capacitance C1 between the inner copper skin and the wire on the left, the capacitance Cw1 between the outer copper skin and the wire, the capacitance CA1 between the two copper skins, and the capacitance Cx of the outer copper skin to ground; the capacitance C2 between the inner copper skin and the wire in the middle, the capacitance Cw2 between the outer copper skin and the wire, the capacitance CA2 between the two copper skins in the middle, and the capacitance Cx of the outer copper skin to ground; the capacitance C3 between the inner copper skin and the wire on the right, the capacitance Cw3 between the outer copper skin and the wire, the capacitance CA3 between the two copper skins, the capacitance Cx of the outer copper skin to ground, and the voltage UA.

[0007] As a preferred solution of the three-probe anti-interference single-phase displacement current method described in the present invention, wherein: the conversion of the displacement current into the conduction current includes, when the Gaussian surface S1 completely wraps the inner copper sheet, using Maxwell's full current law:

[0008]

[0009] According to the second type of surface integral properties, the above formula is equivalent to:

[0010]

[0011] When the operational amplifier is running in a closed loop, the potential between the two copper sheets is equal, that is: u α1 =u α2 , since the potential between the two layers of copper is the same, any path L starting from the inner copper and ending at the outer copper satisfies:

[0012]

[0013] The electric displacement vector D1 between the two layers of copper is 0, so have to That is, the conduction current i flowing into the converter is equal to the displacement current flowing through C0.

[0014] As a preferred solution of the three-probe anti-interference single-phase displacement current method described in the present invention, when the Gaussian surface S2 wraps two copper sheets but does not wrap the power line, Maxwell's full current law is used again to obtain:

[0015]

[0016] Since the normal direction of the upper half of S2 is opposite to that of D, the flow through C0 and C x The displacement current is the same as the conduction current flowing through the converter, both are i. From KCL and KVL, we can get:

[0017] (UA-u α1 )·jωC0=u α2 ·jωC x

[0018] u α2 ·jωC x =i

[0019] Lianliu α1 =u α2 have to:

[0020] From this we can get:

[0021]

[0022] As a preferred solution of the three-probe anti-interference single-phase displacement current method described in the present invention, wherein: the full-rank equation group includes, obtained from the equivalent circuit diagram:

[0023] UA=|k1|·i1,UA=|k2|·i2,UA=|k3|·i3 (1-10)

[0024]

[0025] According to KCL:

[0026]

[0027] As a preferred solution of the three-probe anti-interference single-phase displacement current method described in the present invention, wherein: by combining the two formulas (1-12) and (1-13), eliminating Cx, UA can be obtained, and the UA value is named UA1:

[0028]

[0029] Combining equations (1-13) and (1-14), eliminating Cx, we can get UA, and the UA value is named UA2:

[0030]

[0031] Combining equations (1-12) and (1-13), eliminating Cx, we can get UA, and the UA value is named UA3:

[0032]

[0033] As a preferred solution of the three-probe anti-interference single-phase displacement current method described in the present invention, the average value of the three UA is obtained to obtain the final U A总 Combining (1-15), (1-16), and (1-17), we get:

[0034]

[0035] On the second aspect, another object of the present invention is to provide a three-probe anti-interference single-phase displacement current structure, including: three copper-clad areas, a cylindrical electrode, a measuring circuit, an end cover, and a power line; the left area of ​​the copper-clad area is copper-clad inside and outside, and the inner copper length is the same as the outer copper length; the middle area is copper-clad inside and outside, and the length of the outer copper is the same as the length of the outer copper on the left, the length of the outer copper is greater than the length of the inner copper, and the inner copper is two-thirds of the outer copper; the right area is copper-clad inside and outside, and the length of the outer copper is the same as the outer copper on the left, but the length of the outer copper is greater than the length of the inner copper, and the inner copper is one-third of the outer copper.

[0036] In a third aspect, a computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the three-probe anti-interference single-phase displacement current method as described above are implemented.

[0037] In a fourth aspect, a computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the three-probe anti-interference single-phase displacement current method as described above.

[0038] Beneficial effects of the present invention: The three-probe anti-interference single-phase displacement current method and structure provided by the present invention adopts a single-phase displacement current method, which measures the displacement current generated by the voltage between two layers of copper foil, and converts the displacement current between conductors into a conduction current. Through the coupling mechanism of the three probes, the impedance value between the two layers of copper foil is changed to obtain the response value of the device under different resistance values ​​of the two copper foils. The non-invasive measurement method of the displacement current method is equivalent to short-circuiting the two layers of copper foil and measuring its short-circuit current. Through the coupling structure of the three probes and the line to form a differential coupling capacitance, a full-rank set of equations is obtained, thereby eliminating the interference of the ground capacitance CX to achieve the anti-interference of the displacement current method, enhance the anti-interference of the method, and thus improve the performance of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0040] Figure 1 An overall flow chart of a three-probe anti-interference single-phase displacement current method provided by an embodiment of the present invention;

[0041] Figure 2 A diagram of a single-phase power line voltage measurement device using a three-probe anti-interference single-phase displacement current method provided by one embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a single-phase power line voltage measurement method based on a displacement current method and a three-probe anti-interference single-phase displacement current method provided by an embodiment of the present invention;

[0043] Figure 4 A diagram of the single-phase power line displacement current-conduction current conversion mechanism of a three-probe anti-interference single-phase displacement current method provided by one embodiment of the present invention;

[0044] Figure 5 A circuit schematic diagram of a three-probe anti-interference single-phase displacement current method provided by one embodiment of the present invention;

[0045] Figure 6An equivalent circuit diagram of a three-probe anti-interference single-phase displacement current method provided by one embodiment of the present invention;

[0046] Figure 7 A coupling mechanism diagram of a three-probe anti-interference displacement current method of a three-probe anti-interference single-phase displacement current structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0048] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0049] Example 1

[0050] Reference Figure 1 to Figure 6 , as an embodiment of the present invention, provides a three-probe anti-interference single-phase displacement current method, comprising:

[0051] S1: Copper is pasted inside and outside the three areas to make the three-probe anti-interference single-phase displacement current and power line form an equivalent circuit;

[0052] Furthermore, the two parameters that affect the accuracy of non-contact voltage measurement are related to the coupling mechanism. The first is the coupling capacitance C0 between the coupling mechanism and the power line and the capacitance C between the coupling mechanism and the earth. x The more stable these two parameters are, the higher the measurement accuracy is. When the height of the device changes, the capacitance C between the outer copper skin and the ground x Compared with other parameters, C x The main interference factor is numerical instability. Therefore, the key to anti-interference of the non-invasive voltage measurement method based on displacement current method is to take measures to eliminate C to the maximum extent. x The impact of changes.

[0053] Based on the displacement current method, the single-phase power line voltage measurement device is installed as follows Figure 2 As shown, it includes power lines, coupling mechanisms, insulating support structures, and the ground.

[0054] The equivalent circuit formed by the coupling front end of the measuring device and the environment is as follows: Figure 3 As shown, it includes the inner copper skin capacitance C0 of the line pair, the capacitance between the inner and outer copper skins C1, and the outer copper skin to ground capacitance C x .

[0055] S2: Convert the displacement current into conduction current through the converter;

[0056] The displacement current can be converted into conduction current through the IV converter. The conversion mechanism is analyzed as follows:

[0057] like Figure 4 As shown, assuming that the Gaussian surface S1 completely wraps the inner copper sheet, using Maxwell's full current law

[0058]

[0059] Among them, J: current density; D: electric displacement vector; S: integration path; T: time. According to the second-type surface integral property, the above formula is equivalent to:

[0060]

[0061] Since the high-precision operational amplifier has a very high open-loop gain, when the operational amplifier operates in a closed loop, the potential between the two copper skins can be equal, that is:

[0062] u α1 =u α2 (1-3)

[0063] Since the potential between the two layers of copper is the same, any path L starting from the inner copper and ending at the outer copper satisfies:

[0064]

[0065] From this, we can get that the electric displacement vector D1 between the two layers of copper is 0, so (1-2) Available That is, the conduction current i flowing into the IV converter is equal to the displacement current flowing through C0.

[0066] Similarly, assume that the Gaussian surface S2 wraps the two copper sheets but does not wrap the power lines. Using Maxwell's total current law again, we can get:

[0067]

[0068] Since the normal direction of the upper half of S2 is opposite to that of D, it can be obtained that the flow passes through C0, C x The displacement current is equal.

[0069] From the above analysis, we can know that the current flowing through C0 and C xThe displacement current is the same as the conduction current flowing through the IV converter, both are i. From KCL and KVL, we can get:

[0070] (UA-u α1 )·jωC0=u α2 ·jωC x (1-6)

[0071] u α2 ·jωC x =i (1-7)

[0072] j is a unit imaginary number, ω is the angular frequency, and the three equations (1-3), (1-6), and (1-7) are combined to obtain:

[0073]

[0074] From this we can get

[0075]

[0076] Rf2 is the feedback resistor; u1 is the output voltage. Therefore, the non-invasive measurement method based on displacement current method is equivalent to short-circuiting two layers of copper and measuring their short-circuit current.

[0077] The displacement current method has defects: changes in the external environment can easily affect the value of the outer copper skin to ground capacitance Cx, thereby affecting the "ratio" and causing errors. Therefore, the three-probe anti-interference single-phase displacement current method is introduced to eliminate Cx to the maximum extent. x The impact of changes.

[0078] The three-probe structure based on the displacement current method forms different coupling capacitances with the line through the coupling structure of the three probes, and obtains a full-rank equation group, thereby eliminating the interference of the ground capacitance CX.

[0079] In order to reduce the capacitance C x In order to understand the impact of changes, this report changes the impedance value between the two layers of copper foil to obtain the response value of the device under different resistance values ​​of the two copper foils. Through the simultaneous equations, the capacitance variable C to ground is realized. x The elimination of can make the reverse voltage equation not contain the capacitance to ground C x , thereby achieving the device's anti-interference performance.

[0080] The equivalent circuit formed by the three-probe structure and the power line based on the displacement current method is shown in Figure 5, including the capacitance C1 between the inner copper skin and the conductor on the left, the capacitance Cw1 between the outer copper skin and the conductor, the capacitance CA1 between the two copper skins, and the capacitance Cx of the outer copper skin to ground; the capacitance C2 between the inner copper skin and the conductor in the middle, the capacitance Cw2 between the outer copper skin and the conductor, the capacitance CA2 between the two copper skins in the middle, and the capacitance Cx of the outer copper skin to ground; and the capacitance C3 between the inner copper skin and the conductor on the right, the capacitance Cw3 between the outer copper skin and the conductor, the capacitance CA3 between the two copper skins, and the capacitance Cx of the outer copper skin to ground (the outer copper lengths of the three probes are the same. When the edge effect is ignored, the outer copper skin capacitance to ground of the three probes can be considered to be the same).

[0081] S3: Using the coupling structures of the three probes and the different coupling capacitances formed by the lines, a full-rank set of equations is obtained.

[0082] Furthermore, from the analysis, it can be seen that the measurement of displacement current through the IV converter is equivalent to short-circuiting two layers of copper and measuring the short-circuit current flowing through them, so the equivalent measurement principle diagram is as follows Figure 6 shown.

[0083] The principle of the three-probe anti-interference displacement current method is to use the coupling structure of the three probes to form different coupling capacitances with the line to obtain a full-rank equation group, thereby eliminating the interference of the ground capacitance CX.

[0084] From the above equivalent circuit diagram, we can get

[0085] UA=|k1|·i1,UA=|k2|·i2,UA=|k3|·i3 (1-10)

[0086]

[0087] According to KCL,

[0088]

[0089] Combining equations (1-12) and (1-13), eliminating Cx, we can get UA, and the UA value is named UA1:

[0090]

[0091] Combining equations (1-13) and (1-14), eliminating Cx, we can get UA, and the UA value is named UA2:

[0092]

[0093] Combining equations (1-12) and (1-13), eliminating Cx, we can get UA, and the UA value is named UA3:

[0094]

[0095] Finally, the average of the three UAs is calculated to get the final U A总 Combining (1-15), (1-16), and (1-17), we get:

[0096]

[0097] According to the principle of electrostatic field, as long as there is a conductor in the space, a capacitance network will be formed. According to Maxwell's total current law, there will be a virtual current between conductors with different potentials. This current is called displacement current. If there is only one field source in the space, the displacement current between two different conductors is proportional to the field source voltage. If the displacement current can be measured, the field source voltage can be measured. However, the displacement current cannot be measured directly. This chapter uses an IV converter to realize the conversion of displacement current to conduction current, and analyzes its conversion mechanism by analyzing Maxwell's total current theorem, and analyzes its measurement mechanism through a single-phase circuit model. The three-probe structure of the present invention uses a full-rank set of equations to achieve the anti-interference of the displacement current method.

[0098] Example 2

[0099] See also Figure 7 , as an embodiment of the present invention, a three-probe anti-interference single-phase displacement current structure is provided, comprising: three copper-pasted areas, a cylindrical electrode plate, a measuring circuit, an end cover, and a power line;

[0100] The left area is copper-plated inside and outside, and the length of the inner copper is the same as that of the outer copper; the middle area is copper-plated inside and outside, and the length of the outer copper is the same as that of the outer copper on the left, and the length of the outer copper is greater than that of the inner copper, and the inner copper is two-thirds of the outer copper; the right area is copper-plated inside and outside, and the length of the outer copper is the same as that of the outer copper on the left, but the length of the outer copper is greater than that of the inner copper, and the inner copper is one-third of the outer copper.

[0101] Example 3

[0102] An embodiment of the present invention is different from the first two embodiments in that:

[0103] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

[0104] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0105] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0106] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0107] Example 4

[0108] As an embodiment of the present invention, a three-probe anti-interference single-phase displacement current method is provided. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0109] Before the power line is connected, use three probes to measure the baseline current without any interference. Introduce the interference source of the power line (simulate external interference, such as ground current, electromagnetic interference, etc.). Change the capacitance value at the position of the three probes and record the response data.

[0110] Compare the system response under different copper impedance values, and the relationship between the conduction current and displacement current after eliminating the ground capacitance interference. Eliminate unnecessary interference through full rank equations and KCL / KVL analysis.

[0111] The experimental results are shown in the following table:

[0112]

[0113] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A three-probe anti-interference single-phase displacement current method, characterized in that: include: Copper is pasted inside and outside the three areas to make the three-probe anti-interference single-phase displacement current and the power line form an equivalent circuit; The displacement current is converted into a conduction current by a converter; The full-rank equations are obtained by using the coupling structures of the three probes and the different coupling capacitances formed by the lines.

2. The three-probe anti-interference single-phase displacement current method according to claim 1, characterized in that: The equivalent circuit includes the capacitance C1 between the inner copper skin and the wire on the left, the capacitance Cw1 between the outer copper skin and the wire, the capacitance CA1 between the two copper skins, and the capacitance Cx between the outer copper skin and the ground; the capacitance C2 between the inner copper skin and the wire in the middle, the capacitance Cw2 between the outer copper skin and the wire, the capacitance CA2 between the two copper skins in the middle, and the capacitance Cx between the outer copper skin and the ground; the capacitance C3 between the inner copper skin and the wire on the right, the capacitance Cw3 between the outer copper skin and the wire, the capacitance CA3 between the two copper skins, the capacitance Cx between the outer copper skin and the ground, and the voltage UA.

3. The three-probe anti-interference single-phase displacement current method according to claim 2, characterized in that: The conversion of the displacement current into the conduction current includes, when the Gaussian surface S1 completely wraps the inner copper sheet, using Maxwell's total current law: According to the second type of surface integral properties, the above formula is equivalent to: When the operational amplifier is running in a closed loop, the potential between the two copper sheets is equal, that is: u α1 =u α2 (1-3), since the potential between the two layers of copper is the same, any path L starting from the inner copper and ending at the outer copper satisfies: The electric displacement vector D1 between the two layers of copper is 0, so have to That is, the conduction current i flowing into the converter is equal to the displacement current flowing through C0.

4. The three-probe anti-interference single-phase displacement current method according to claim 3, characterized in that: When the Gaussian surface S2 wraps around the two copper sheets but does not wrap around the power lines, Maxwell's full current law is used again to obtain: Since the normal direction of the upper half of S2 is opposite to that of D, the flow through C0 and C x The displacement current is the same as the conduction current flowing through the converter, both are i. From KCL and KVL, we can get: (UA-u α1 )·jωC0=u α2 ·jωC x (1-6) u α2 ·jωC x =i (1-7) Lianliu α1 =u α2 have to: From this we can get:

5. The three-probe anti-interference single-phase displacement current method according to claim 4, characterized in that: The full rank equations include, from the equivalent circuit diagram: UA=|k1|·i1,UA=|k2|·i2,UA=|k3|·i3 (1-10) According to KCL:

6. The three-probe anti-interference single-phase displacement current method according to claim 5, characterized in that: Combining formulas (1-12) and (1-13), eliminating Cx, we can get UA, which is named UA1: Combining equations (1-13) and (1-14), eliminating Cx, we can get UA, and the UA value is named UA2: Combining equations (1-12) and (1-13), eliminating Cx, we can get UA, and the UA value is named UA3:

7. The three-probe anti-interference single-phase displacement current method according to claim 6, characterized in that: Take the average of the three UAs to get the final U A总 Combining (1-15), (1-16), and (1-17), we get:

8. A structure using the three-probe anti-interference single-phase displacement current method as claimed in any one of claims 1 to 7, characterized in that: include: Three copper-clad areas, cylindrical plates, measuring circuits, end caps, and power lines; The left area of ​​the copper-plated area is copper-plated both inside and outside, and the length of the inner copper is the same as that of the outer copper; the middle area is copper-plated both inside and outside, and the length of the outer copper is the same as that of the outer copper on the left, and the length of the outer copper is greater than that of the inner copper, and the inner copper is two-thirds of the outer copper; the right area is copper-plated both inside and outside, and the length of the outer copper is the same as that of the outer copper on the left, but the length of the outer copper is greater than that of the inner copper, and the inner copper is one-third of the outer copper.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the three-probe anti-interference single-phase displacement current method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the three-probe anti-interference single-phase displacement current method described in any one of claims 1 to 7 are implemented.

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