Non-contact voltage inversion optimization method and system based on displacement current method

Abstract

The invention discloses a non-contact voltage inversion optimization method and system based on a displacement current method, and relates to the technical field of power distribution network voltage measurement, and the method is characterized in that an equivalent circuit diagram of a double-coupling mechanism is drawn based on the displacement current method; determining an initial inversion model of the line voltage according to a transfer function between the measurement current and the line voltage in the equivalent circuit diagram, and determining the sensitivity of each measurement parameter in the initial inversion model by analyzing an error transfer and amplification mechanism; determining an error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter; determining a tangent line of the error influence coefficient at the minimum fluctuation value in the measured data, and describing the error influence coefficient in the initial inversion model by using the tangent line to obtain an optimized inversion model; and inputting the measured data into the optimized inversion model, and performing inversion to obtain the line voltage. According to the invention, high-precision non-contact voltage measurement is realized by reducing the parameter sensitivity.

Description

Technical Field

[0001] The present invention relates to the technical field of voltage measurement of distribution network, and more specifically, to a non-contact voltage inversion optimization method and system based on a displacement current method. Background Art

[0002] With the large-scale grid connection of power electronic loads, the distribution network has shown stronger nonlinearity, and it is difficult to infer the operating status of the distribution network through sparse and local voltage data. Therefore, extensive and comprehensive acquisition of voltage data at each node of the distribution network is of great significance to daily grid dispatching, relay protection and other aspects.

[0003] At present, voltage measurement in distribution networks is mainly divided into two categories: contact measurement and non-contact measurement. Among them, contact voltage measurement is represented by two types of transformers: electromagnetic (Potential Transformer, PT) and capacitive (Capacitive Voltage Transformer, CVT). Although this method can measure the line voltage more accurately, the line and the grounding body are metallically connected through the transformer. If it is widely deployed in various distribution lines, the short circuit risk of the distribution network system will increase. In addition, due to the large size and heavy weight of the contact transformer, it is inconvenient to install and is not conducive to its widespread deployment. The non-contact voltage measurement transformer has no direct metal contact with the measurement line, which makes its insulation structure simple, and can be miniaturized and lightweight, thereby making up for the shortcomings of contact voltage measurement. Therefore, non-contact voltage measurement devices are expected to be widely deployed in distribution networks and reduce the voltage monitoring blind spots of distribution networks. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the purpose of the present invention is to provide a non-contact voltage inversion optimization method and system based on the displacement current method. Based on the dual coupling mechanism, the sensitivity of each parameter of the dual coupling mechanism is analyzed based on the displacement current method; then the voltage error amplification mechanism is analyzed to determine the main amplified coefficient; by changing the amplification error and the measured voltage slope, the minimum fluctuation value of the voltage error is determined; then the tangent at the minimum fluctuation value describes the error influence coefficient in the initial inversion model, and high-precision non-contact voltage measurement is achieved by reducing the parameter sensitivity.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions:

[0006] In a first aspect, a non-contact voltage inversion optimization method and system based on a displacement current method are provided, comprising the following steps:

[0007] Draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method;

[0008] The initial inversion model of the line voltage is determined based on the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and the sensitivity of each measurement parameter in the initial inversion model is determined by analyzing the error transmission and amplification mechanism;

[0009] Determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter;

[0010] Determine the tangent line of the error influence coefficient at the minimum fluctuation value in the measured data, and use the tangent line to describe the error influence coefficient in the initial inversion model to obtain the optimized inversion model;

[0011] The measured data is input into the optimized inversion model and the line voltage is obtained by inversion.

[0012] Furthermore, the dual coupling mechanism includes two coupling mechanisms, and the medium between the circuit and the inner copper pole in the two coupling mechanisms is different.

[0013] Furthermore, the expression of the initial inversion model is specifically:

[0014]

[0015] Where, U represents the line voltage; u 1 represents the first measurement voltage measured by the first coupling mechanism; u 2 represents the second measured voltage of the second coupling mechanism; b represents the first parameter; r represents the second parameter; C 1 Represents the equivalent capacitance between the line and the inner copper electrode in the first coupling mechanism; C 2 Represents the equivalent capacitance between the line and the inner copper electrode in the second coupling mechanism; C 3 Represents the equivalent capacitance between the line and the outer copper electrode in the first coupling mechanism; C 4 represents the equivalent capacitance between the line and the outer copper pole in the second coupling mechanism; ω represents the frequency of the line under different working conditions; R f Indicates the equivalent operational resistance in the measurement circuit.

[0016] Furthermore, the measurement parameters include a first measurement voltage, a second measurement voltage, a first parameter and a second parameter.

[0017] Furthermore, the expression of the error influence coefficient is:

[0018]

[0019] Among them, f(u 2 / u 1 ) represents the characterization function of the error influence coefficient.

[0020] Furthermore, the process of determining the tangent line of the error influence coefficient at the minimum fluctuation value in the measured data is specifically as follows:

[0021] The ratio of the two measured voltages in the two coupling mechanisms is taken as the fluctuation value;

[0022] The smallest fluctuation value among all measured data is selected as the minimum fluctuation value;

[0023] A tangent point with a minimum fluctuation value as the abscissa is selected from the error influence coefficient, and the tangent line corresponding to the tangent point is used as the tangent line of the error influence coefficient at the minimum fluctuation value.

[0024] Furthermore, the expression of the optimized inversion model is specifically:

[0025]

[0026] Where, U represents the line voltage; u 1 represents the first measurement voltage measured by the first coupling mechanism; u 2 represents the second measured voltage of the second coupling mechanism; b represents the first parameter; r represents the second parameter; (u 2 / u 1 ) min Indicates the minimum fluctuation value.

[0027] In a second aspect, a non-contact voltage inversion optimization system based on a displacement current method is provided, the system is used to implement the non-contact voltage inversion optimization method based on a displacement current method as described in any one of the first aspects, comprising:

[0028] An equivalent processing module is used to draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method;

[0029] A sensitivity analysis module is used to determine the initial inversion model of the line voltage based on the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and to determine the sensitivity of each measurement parameter in the initial inversion model by analyzing the error transmission and amplification mechanism;

[0030] An error analysis module is used to determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter;

[0031] An inversion optimization module is used to determine the tangent of the error influence coefficient at the minimum fluctuation value in the measured data, and to describe the error influence coefficient in the initial inversion model with the tangent to obtain an optimized inversion model;

[0032] The voltage inversion module is used to input the measured data into the optimized inversion model to invert the line voltage.

[0033] In a third aspect, a computer terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a non-contact voltage inversion optimization method based on the displacement current method as described in any one of the first aspects is implemented.

[0034] In a fourth aspect, a computer-readable medium is provided, on which a computer program is stored, and the computer program is executed by a processor to implement the non-contact voltage inversion optimization method based on the displacement current method as described in any one of the first aspects.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The non-contact voltage inversion optimization method based on the displacement current method provided by the present invention is based on a dual coupling mechanism, and analyzes the sensitivity of each parameter of the dual coupling mechanism based on the displacement current method; then analyzes the voltage error amplification mechanism to determine the main amplified coefficient; by changing the amplified error and the measured voltage slope, the minimum fluctuation value of the voltage error is determined; and the tangent at the minimum fluctuation value describes the error influence coefficient in the initial inversion model, and achieves high-precision non-contact voltage measurement by reducing the parameter sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0038] Figure 1 is a flow chart of Embodiment 1 of the present invention;

[0039] Figure 2 is a measurement principle diagram of the double coupling mechanism in Example 1 of the present invention;

[0040] Figure 3 is the equivalent circuit diagram in Embodiment 1 of the present invention;

[0041] Figure 4 This is a schematic diagram of desensitization in Example 1 of the present invention;

[0042] Figure 5 This is a schematic diagram of data selection in the observation window in Example 1 of the present invention;

[0043] Figure 6 System block diagram in embodiment 2 of the present invention. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0045] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to the other component.

[0046] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0047] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0048] Embodiment 1: Non-contact voltage inversion optimization method based on displacement current method, such as Figure 1 As shown, the following steps are included:

[0049] S1: Draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method;

[0050] S2: Determine the initial inversion model of the line voltage based on the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and determine the sensitivity of each measurement parameter in the initial inversion model by analyzing the error transmission and amplification mechanism;

[0051] S3: Determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter;

[0052] S4: determining the tangent line of the error influence coefficient at the minimum fluctuation value in the measured data, and using the tangent line to describe the error influence coefficient in the initial inversion model to obtain an optimized inversion model;

[0053] S5: Input the measured data into the optimized inversion model to obtain the line voltage through inversion.

[0054] In step S1, if Figure 2As shown in the figure, the dual coupling mechanism is realized by a non-contact voltage sensor. The right side is the original single coupling mechanism, which is defined as the first coupling mechanism; the left side is the added auxiliary coupling mechanism, which is defined as the second coupling mechanism. The two coupling mechanisms differ only in the medium between the line and the inner copper foil (inner copper pole). The left side is filled with a medium with a relative dielectric constant greater than 1, and the right side is not filled with air as the medium. Therefore, the capacitance to ground of the left and right couplings is equal, and there is only a difference in the capacitance between the line and the plate.

[0055] like Figure 3 As shown in the figure, based on the electric field relationship between the line and the probe, the equivalent measurement principle diagram of the double coupling mechanism displacement current method can be drawn. Figure 3 Middle C 1 , C 3 They represent the equivalent capacitance formed by the line (conductor) and the inner and outer copper poles of the left coupling mechanism, respectively. 2 , C 4 They represent the equivalent capacitance formed by the wire and the inner and outer copper poles of the coupling mechanism on the right.

[0056] When the double coupling mechanism is set up at a voltage of U A When the wire is connected, the response voltage of the coupling mechanism on the left and right sides is different. The signal processing circuit on the left and right sides realizes voltage measurement.

[0057] In step S2, the circuit voltage U is derived according to the equivalent circuit diagram. A The measured voltage u of the sensor 1 、u 2 And the coupling capacitance expression, the line voltage inversion model can be obtained.

[0058] The dual coupling mechanism indirectly measures the current between the inner and outer copper poles by measuring the transimpedance voltage, and then inverts the line voltage. The function of the IV converter is to short-circuit the inner and outer copper poles and measure the short-circuit current flowing through them. Figure 3 The analysis shows that:

[0059]

[0060] Where, U represents the line voltage; u 1 represents the first measurement voltage measured by the first coupling mechanism; u 2 Represents the second measured voltage of the second coupling mechanism; C 1 Represents the equivalent capacitance between the line and the inner copper electrode in the first coupling mechanism; C 2 Represents the equivalent capacitance between the line and the inner copper electrode in the second coupling mechanism; C 3 Represents the equivalent capacitance between the line and the outer copper electrode in the first coupling mechanism; C 4 represents the equivalent capacitance between the line and the outer copper pole in the second coupling mechanism; ω represents the frequency of the line under different working conditions; R fIndicates the equivalent operational resistance in the measurement circuit.

[0061] The combined equations (1) and (2) can eliminate the ground capacitance C x The influence on the measured voltage, thus obtaining the line voltage U A The derivation formula is:

[0062]

[0063] Wherein, b represents the first parameter; r represents the second parameter.

[0064] According to formula (4), using the calibration values ​​of r, b and the measured value u of the device under actual working conditions 1 、u 2 , the line voltage can be inverted, avoiding the influence of the change of ground capacitance on the measurement accuracy.

[0065] By analyzing the error transmission and amplification mechanism, the quantitative expression of parameter sensitivity is obtained, and then a method to reduce parameter sensitivity is proposed.

[0066] The second parameter r is the quantitative relationship between the error percentage and the inversion voltage error percentage, so the relative error δ of the inversion voltage is U The relative error δ with parameter r r By comparison, we can characterize the multiple of error transmission, the sensitivity of r parameter:

[0067]

[0068] The geometric meaning of parameter sensitivity is: the ratio of the slope of the tangent line of the inversion voltage model at the true value point of the parameter to the slope of the secant line at the zero-crossing point. This is consistent with the results of qualitative analysis. When the tangent slope of the inversion voltage curve is higher and the nonlinearity is more serious, the parameter sensitivity is higher.

[0069] The sensitivity of the four parameters of the voltage inversion formula is obtained as follows:

[0070]

[0071] In step S3, the main influencing factors with high sensitivity are determined according to the partial derivatives of the sensitivity errors of each parameter.

[0072] The inversion voltage error caused by the error in parameter b does not increase with the voltage inversion formula. The reason for the amplification of the inversion voltage error is that the parameters r and u 1 、u 2 The high sensitivity of the voltage inversion formula is only related to the parameter u after the parameters r and b are calibrated in advance. 1 、u 2 related.

[0073] According to the voltage inversion formula of the dual-coupling mechanism displacement current method, it can be written as follows:

[0074] U=f(u 2 / u 1 )·u 2 (10);

[0075]

[0076] When the response voltage u 2 or 1 There is an error, and the total differential of the above formula can be obtained:

[0077]

[0078] is u 1 、u 2 The main factor by which the relative error is amplified is also the main reason why the inversion voltage model has high parameter sensitivity.

[0079] In step S4, after determining the main factors affecting the error, the fluctuation of the measured value is analyzed, and the influence of the measurement on the inverted line voltage is reduced by changing the slope.

[0080] like Figure 4 As shown, f(u 2 / u 1 ) is formally about u 2 / u 1 The inverse proportional function of the parameter r can be seen by analyzing the expression of u 2 / u 1 In C x = 0 coincides with the value of r, but in actual measurement, the value of the capacitance to ground is smaller, making u 2 / u 1 is close to r, then f(u 2 / u 1 ) has a larger slope, which makes f(u 2 / u 1 ) in u 2 / u 1 The measured value u 1 、u 2 When fluctuating, a wider fluctuation band appears.

[0081] Figure 4 middle(u 2 / u 1 ) min 、(u 2 / u 1 ) 0 、(u 2 / u 1) max They respectively represent the measured values ​​(u 2 / u 1 )'s minimum fluctuation lower limit, true value, and maximum fluctuation upper limit. 2 / u 1 ) max 、f(u 2 / u 1 ) 0 、f(u 2 / u 1 ) min They are f(u 2 / u 1 )’s upper limit, true value and lower limit.

[0082] Since in actual measurement, f(u 2 / u 1 ) has a large slope, making f(u 2 / u 1 ) in u 2 / u 1 The measured value u 1 、u 2 When fluctuating, a wider fluctuation band appears.

[0083] Further observation shows that when u 2 / u 1 When it is closer to r, f(u 2 / u 1 ) increases sharply, making (u 2 / u 1 ) is greater than (u 2 / u 1 ) 0 This part of the error is further amplified, thus reducing the proportionality factor f(u 2 / u 1 ) can be reduced by appropriately reducing the slope angle.

[0084] because:

[0085] Therefore f(u 2 / u 1 ) has a monotonically increasing slope. 2 / u 1 ) min is the smallest, in order to reduce f(u 2 / u 1 ) parameter sensitivity, which can be measured by (u 2 / u 1 ) min The tangent line l(u 2 / u 1) describes f(u 2 / u 1 ) value, thereby reducing f(u 2 / u 1 ) is analyzed as follows:

[0086]

[0087] Where: η∈((u 2 / u 1 ) min ,(u 2 / u 1 ) max )

[0088]

[0089] According to formula (13), we can get: f'((u 2 / u 1 ) min )<f'(η), and then we can get Δ 1 >Δ 2 Therefore, under certain working conditions, (u 2 / u 1 )The tangent line l(u 2 / u 1 ) describes the proportionality factor f(u 2 / u 1 ) will reduce the parameter u 1 、u 2 The absolute error caused by fluctuations ultimately further reduces the parameter sensitivity of the proportional coefficient.

[0090] Therefore, in the actual measurement process, a data observation window with a length of L can be set to store (u 2 / u 1 ) data to obtain the maximum value (u 2 / u 1 ) max With the minimum value (u 2 / u 1 )min, such as Figure 5 As shown, new data enters the observation window from the end and old data flows out from the head.

[0091] Assume (u 2 / u 1 ) min is the data observation window with length L (u 2 / u 1 ) has the smallest value. According to the analysis, the desensitization form of the inversion voltage formula is:

[0092]

[0093] (u 2 / u 1 )min needs to be limited to avoid 2 / u 1 There are abnormal data that make the true value f(u 2 / u 1 ) 0 Appears on the tangent line l(u 2 / u 1 ) outside the fluctuation band.

[0094] The limiting expression is:

[0095]

[0096] In the formula, Indicates that (u 2 / u 1 ) is a rough estimate of the true value.

[0097] Embodiment 2: Non-contact voltage inversion optimization system based on displacement current method: This system is used to implement the non-contact voltage inversion optimization method based on displacement current method as described in Embodiment 1, such as Figure 6 As shown, it includes an equivalent processing module, a sensitivity analysis module, an error analysis module, an inversion optimization module and a voltage inversion module.

[0098] Among them, the equivalent processing module is used to draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method; the sensitivity analysis module is used to determine the initial inversion model of the line voltage according to the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and determine the sensitivity of each measurement parameter in the initial inversion model by analyzing the error transmission and amplification mechanism; the error analysis module is used to determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter; the inversion optimization module is used to determine the tangent of the error influence coefficient at the minimum fluctuation value in the measured data, and use the tangent to describe the error influence coefficient in the initial inversion model to obtain the optimized inversion model; the voltage inversion module is used to input the measured data into the optimized inversion model to invert the line voltage.

[0099] The present invention also describes a computer terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the non-contact voltage inversion optimization method based on the displacement current method as described in Example 1 is implemented.

[0100] The present invention also describes a computer-readable medium on which a computer program is stored. The computer program is executed by a processor to implement the non-contact voltage inversion optimization method based on the displacement current method as described in Example 1.

[0101] Working principle: The present invention is based on a dual coupling mechanism and analyzes the sensitivity of each parameter of the dual coupling mechanism based on the displacement current method; then the voltage error amplification mechanism is analyzed to determine the main coefficient to be amplified; by changing the amplified error and the measured voltage slope, the minimum fluctuation value of the voltage error is determined; and the tangent at the minimum fluctuation value describes the error influence coefficient in the initial inversion model, and high-precision non-contact voltage measurement is achieved by reducing parameter sensitivity.

[0102] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0103] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0106] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A non-contact voltage inversion optimization method and system based on displacement current method, characterized in that: The following steps are involved: Draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method; The initial inversion model of the line voltage is determined based on the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and the sensitivity of each measurement parameter in the initial inversion model is determined by analyzing the error transmission and amplification mechanism; Determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter; Determine the tangent line of the error influence coefficient at the minimum fluctuation value in the measured data, and use the tangent line to describe the error influence coefficient in the initial inversion model to obtain the optimized inversion model; The measured data is input into the optimized inversion model and the line voltage is obtained by inversion.

2. The non-contact voltage inversion optimization method and system based on the displacement current method according to claim 1 is characterized in that: The dual coupling mechanism comprises two coupling mechanisms, and the medium between the circuit and the inner copper pole in the two coupling mechanisms is different.

3. The non-contact voltage inversion optimization method and system based on displacement current method according to claim 1 is characterized in that: The expression of the initial inversion model is specifically: Wherein, U represents the line voltage; u1 represents the first measured voltage measured by the first coupling mechanism; u2 represents the second measured voltage of the second coupling mechanism; b represents the first parameter; r represents the second parameter; C1 represents the equivalent capacitance between the line and the inner copper pole in the first coupling mechanism; C2 represents the equivalent capacitance between the line and the inner copper pole in the second coupling mechanism; C3 represents the equivalent capacitance between the line and the outer copper pole in the first coupling mechanism; C4 represents the equivalent capacitance between the line and the outer copper pole in the second coupling mechanism; ω represents the frequency of the line under different working conditions; R f Indicates the equivalent operational resistance in the measurement circuit.

4. The non-contact voltage inversion optimization method and system based on displacement current method according to claim 3 is characterized in that: The measurement parameters include a first measurement voltage, a second measurement voltage, a first parameter, and a second parameter.

5. The non-contact voltage inversion optimization method and system based on displacement current method according to claim 3 is characterized in that: The expression of the error influence coefficient is: Among them, f(u2 / u1) represents the characterization function of the error influence coefficient.

6. The non-contact voltage inversion optimization method and system based on displacement current method according to claim 1 is characterized in that: The process of determining the tangent line of the error influence coefficient at the minimum fluctuation value in the measured data is specifically as follows: The ratio of the two measured voltages in the two coupling mechanisms is taken as the fluctuation value; Select the smallest fluctuation value among all measured data as the minimum fluctuation value; A tangent point with a minimum fluctuation value as the abscissa is selected from the error influence coefficient, and the tangent line corresponding to the tangent point is used as the tangent line of the error influence coefficient at the minimum fluctuation value.

7. The non-contact voltage inversion optimization method and system based on displacement current method according to claim 1 is characterized in that: The expression of the optimized inversion model is specifically: Wherein, U represents the line voltage; u1 represents the first measured voltage measured by the first coupling mechanism; u2 represents the second measured voltage of the second coupling mechanism; b represents the first parameter; r represents the second parameter; (u2 / u1) min Indicates the minimum fluctuation value.

8. A non-contact voltage inversion optimization system based on displacement current method, characterized in that: The system is used to implement the non-contact voltage inversion optimization method based on the displacement current method as described in any one of claims 1 to 7, comprising: An equivalent processing module is used to draw the equivalent circuit diagram of the dual coupling mechanism based on the displacement current method; A sensitivity analysis module is used to determine the initial inversion model of the line voltage based on the transfer function between the measured current and the line voltage in the equivalent circuit diagram, and to determine the sensitivity of each measurement parameter in the initial inversion model by analyzing the error transmission and amplification mechanism; An error analysis module is used to determine the error influence coefficient according to the error partial derivative of the sensitivity of each measurement parameter; An inversion optimization module is used to determine the tangent of the error influence coefficient at the minimum fluctuation value in the measured data, and to describe the error influence coefficient in the initial inversion model with the tangent to obtain an optimized inversion model; The voltage inversion module is used to input the measured data into the optimized inversion model to invert the line voltage.

9. A computer terminal comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the non-contact voltage inversion optimization method based on the displacement current method as described in any one of claims 1 to 7 is implemented.

10. A computer readable medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the non-contact voltage inversion optimization method based on the displacement current method as described in any one of claims 1 to 7.

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