A method and apparatus for measuring parameters of a double-circuit transmission line.

Abstract

This application discloses a method and device for measuring parameters of a double-circuit transmission line. It involves periodically acquiring voltage and current signals from the beginning and end of each phase of the double-circuit transmission line. Two sets of voltage moduli and two sets of current moduli are generated based on the voltage and current signals. The resistance and inductance moduli are calculated from the first set of moduli, and then inverse phase-mode transformation is performed to obtain the resistance and inductance phase parameters. A phase sequence transformation is then performed to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line. Similarly, the capacitance moduli of the double-circuit transmission line are calculated from the second set of moduli, and then inverse phase-mode transformation is performed to obtain the capacitance phase parameters. A phase sequence transformation is then performed to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line. This method enables simultaneous measurement of positive-sequence impedance and zero-sequence impedance and capacitive reactance parameters of the line without power outages or changes to the transmission line's operating mode. It offers high measurement accuracy and is simple and cost-effective.

Description

Technical Field

[0001] This application relates to the field of transmission line parameter measurement technology, and in particular to a method and device for measuring the parameters of a double-circuit transmission line. Background Technology

[0002] Transmission lines are an indispensable part of the power system. Due to the rapid development of society and the economy, the demand for electricity is increasing day by day, the coverage of the power system is becoming wider and wider, and the number of transmission lines is also increasing. However, due to the limitation of land resources, multi-circuit parallel lines have become the primary choice for new lines. Moreover, double-circuit lines on the same tower have gradually become the main mode of power transmission due to their advantages such as small footprint, high economic value, and simple operation and maintenance.

[0003] Due to environmental factors, the parameters of transmission lines during operation often differ from theoretical values. Accurate acquisition of transmission line parameters is crucial for ensuring the normal operation of the power system. Precise line parameters ensure that calculations such as protection settings, power flow calculations, and fault calculations are closer to reality, thereby reducing the potential for transmission line faults. Therefore, relevant regulations stipulate that the parameters of transmission lines must be measured in practice.

[0004] For parameters of double-circuit transmission lines, the existing method involves measuring the positive-sequence and zero-sequence parameters of the double-circuit transmission line separately by shutting down the power supply or changing the line's pressurization and operation modes. Furthermore, a single measurement can only calculate the corresponding sequence parameter. This parameter measurement method is complex to operate, and power outages and changes in line pressurization and operation modes will affect the normal use of electricity, resulting in significant consumption and loss of manpower and property.

[0005] Therefore, how to measure various parameters of a double-circuit transmission line without power outages or changes in line operation is a technical problem that needs to be solved. Summary of the Invention

[0006] The main objective of this application is to provide a method and device for measuring the parameters of a double-circuit transmission line, aiming to solve the technical problem in related technologies that requires power outages and changes in the operation mode of the transmission line in order to measure the parameters of a double-circuit transmission line.

[0007] In a first aspect, this application provides a method for measuring parameters of a double-circuit transmission line, the method comprising the following steps:

[0008] Periodically collect voltage and current signals at the beginning and end of each phase of the double-circuit transmission line;

[0009] A first set of voltage moduli and a second set of voltage moduli are generated by performing phase mode transformation on the voltage signal, and a first set of current moduli and a second set of current moduli are generated by performing phase mode transformation on the current signal.

[0010] The resistance modulus and inductance modulus of the double-circuit transmission line are calculated based on the trapezoidal integral equation of the first set of voltage modulus, the first set of current modulus, and the impedance of the double-circuit transmission line. The phase modulus and inductance modulus are then subjected to inverse phase-modulus transformation to obtain the phase parameters of resistance and inductance. The phase sequence transformation of the phase parameters of resistance and inductance is then performed to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line.

[0011] The capacitance modulus of the double-circuit transmission line is calculated based on the differential equations of the second set of voltage modulus, the second set of current modulus, and the admittance of the double-circuit transmission line. The capacitance modulus is then subjected to inverse phase-mode transformation to obtain the capacitance phase parameters. Finally, the capacitance phase parameters are subjected to phase-sequence transformation to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line.

[0012] In some embodiments, a first set of voltage modulo parameters is generated by performing phase-mode transformation on the voltage signal, and a first set of current modulo parameters is generated by performing phase-mode transformation on the current signal, specifically including the following steps:

[0013] The first voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage at the end of each phase from the sum of the voltages at the beginning of each phase of the double-circuit transmission line.

[0014] U G1 =U 1as +U 1bs +U 1cs +U 2as +U 2bs +U 2cs -U 1am -U 1bm -U 1cm -U 2am -U 2bm -U 2cm

[0015] Among them, U G1 U is the first voltage modulus in the first group of voltage moduli. 1as U is the voltage at the beginning of phase A of the first circuit in a double-circuit transmission line. 1bs U is the voltage at the beginning of phase B of the first transmission line. 1cs U is the voltage at the beginning of phase C of the first transmission line. 2as U is the voltage at the beginning of phase A of the second circuit in a double-circuit transmission line. 2bs U is the voltage at the beginning of phase B of the second transmission line. 2cs U is the voltage at the beginning of phase C of the second transmission line. 1am U is the voltage at the end of phase A of the first transmission line. 1bmU is the voltage at the end of phase B of the first transmission line. 1cm U is the voltage at the end of phase C of the first transmission line. 2am U is the voltage at the end of phase A of the second transmission line. 2bm U is the voltage at the end of phase B of the second transmission line. 2cm This refers to the voltage at the end of phase C of the second transmission line;

[0016] The second voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage difference between the three-phase starting terminals of the first and second transmission lines from the voltage difference between the three-phase starting terminals of the first and second transmission lines.

[0017] U G2 =U 1as +U 1bs +U 1cs -U 2as -U 2bs -U 2cs -(U 1am +U 1bm +U 1cm -U 2am -U 2bm -U 2cm )

[0018] Among them, U G2 The second voltage modulus in the first group of voltage moduli;

[0019] The third voltage modulus in the first set of voltage moduli is obtained by subtracting the voltages at the ends of phases A and C of the first transmission line from the sum of the voltages at the beginning of phases A and C of the first transmission line.

[0020] U L1 =U 1as +U 1cs -U 1am -U 1cm

[0021] Among them, U L1 It is the third voltage modulus in the first group of voltage moduli;

[0022] The first current modulus in the first set of current moduli is obtained by multiplying the sum of the currents at the beginning and end of each phase of the double-circuit transmission line by 0.5.

[0023] I G1 =0.5×(I 1as +I 1bs +I 1cs +I 2as +I 2bs +I 2cs +I1am +I 1bm +I 1cm +I 2am +I 2bm +I 2cm )

[0024] Among them, I G1 I is the first current modulus in the first group of current moduli. 1as I is the current at the beginning of phase A of the first transmission line. 1bs I is the current at the beginning of phase B of the first transmission line. 1cs I is the current at the beginning of phase C of the first transmission line. 2as For the current at the beginning of phase A of the second transmission line, I 2bs For the current at the beginning of phase B of the second transmission line, I 2cs I is the current at the beginning of phase C of the second transmission line. 1am I is the current at the end of phase A of the first transmission line. 1bm I is the current at the end of phase B of the first transmission line. 1cm I is the current at the end of phase C of the first transmission line. 2am I is the current at the end of phase A of the second transmission line. 2bm I is the current at the end of phase B of the second transmission line. 2cm This refers to the current at the end of phase C of the second transmission line;

[0025] The second current modulus in the first set of current moduli is obtained by multiplying the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line, plus the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line, by 0.5.

[0026] I G2 =0.5×(I 1as +I 1bs +I 1cs -I 2as -I 2bs -I 2cs +I 1am +I 1bm +I 1cm -I 2am -I 2bm -I 2cm )

[0027] Among them, I G2 It is the second current modulus in the first group of current moduli;

[0028] The third current modulus in the first set of current moduli is obtained by multiplying the difference in current at the beginning of phase A and phase C of the first transmission line by the difference in voltage at the end of phase A and phase C of the first transmission line, and then multiplying the result by 0.5.

[0029] I L1 =0.5×(I 1as -I 1cs +I 1am -I 1cm )

[0030] Among them, I L1 It is the third current modulus in the first group of current moduli.

[0031] In some embodiments, the resistance modulus and inductance modulus of the double-circuit transmission line are calculated based on the first set of voltage modulus, the first set of current modulus, and the trapezoidal integral equation of the impedance of the double-circuit transmission line. Specifically, this includes the following steps:

[0032] Substituting the voltage and current signals acquired at two adjacent acquisition times into the first set of voltage moduli and the first set of current moduli generated, we obtain the first resistance moduli, the second resistance moduli, the third resistance moduli, the first inductance moduli, the second inductance moduli, and the third inductance moduli by solving the trapezoidal integral equation of the double-circuit transmission line impedance:

[0033]

[0034] Where t1 is the first acquisition time, t2 is the second sampling time, t1 and t2 are two adjacent acquisition times, and T S Sampling period T s =t2-t1, R G1 R is the first resistive modulus. G2 R is the second resistive modulus. L1 The third resistive modulus; L G1 L is the first inductance modulus. G2 L is the second inductance modulus. L1 This is the third inductance modulus.

[0035] In some embodiments, the phase-mode inverse transformation of the resistance modulus and the inductance modulus is performed to obtain the resistance phase parameters and the inductance phase parameters, specifically including the following steps:

[0036] According to the inverse phase-mode transformation formula, the first resistance modulus, the second resistance modulus, the third resistance modulus, the first inductance modulus, the second inductance modulus, and the third inductance modulus are subjected to inverse phase-mode transformation to obtain the self-resistance of the double-circuit transmission line, the mutual resistance between the three phase lines in the double-circuit transmission line, the mutual resistance between the transmission lines of the first circuit and the second circuit, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phase lines in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first circuit and the second circuit:

[0037]

[0038]

[0039] Among them, R s R is the self-resistance of the double-circuit transmission line. m R is the mutual resistance between the three phases in the double-circuit transmission line. c L is the mutual resistance between the first transmission line and the second transmission line. s L is the self-inductance of the double-circuit transmission line. m L is the mutual inductance between the three phases in the double-circuit transmission line. c The mutual inductance between the first transmission line and the second transmission line is denoted as .

[0040] In some embodiments, the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line are obtained by performing phase sequence transformation on the resistive phase parameters and the inductive phase parameters, specifically including the following steps:

[0041] Based on the self-resistance of the double-circuit transmission line, the mutual resistance between the three phases in the double-circuit transmission line, the mutual resistance between the transmission lines of the first and second circuits, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phases in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first and second circuits, the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line.

[0042]

[0043] Where Z1 is the positive-sequence self-impedance of the double-circuit transmission line; Z0 is the zero-sequence self-impedance of the double-circuit transmission line; Z m Let j be the zero-sequence mutual impedance of the double-circuit transmission line, j be the imaginary unit, and ω be the angular velocity.

[0044] In some embodiments, a second set of voltage modulo parameters is generated by performing phase-mode transformation on the voltage signal, and a second set of current modulo parameters is generated by performing phase-mode transformation on the current signal. Specifically, this includes the following steps:

[0045] The first voltage modulus in the second set of voltage moduli is obtained by multiplying the sum of the voltages at the beginning and end of each phase of the double-circuit transmission line by 0.5.

[0046] U' G1 =0.5×(U 1as +U 1bs +U 1cs +U 2as +U 2bs +U 2cs +U 1am +U 1bm +U 1cm +U 2am +U 2bm +U 2cm )

[0047] Among them, U′ G1 This is the first voltage modulus in the second group of voltage moduli;

[0048] The second voltage modulus in the first set of voltage moduli is obtained by multiplying the difference between the voltage at the beginning of the three phases of the first transmission line and the voltage at the beginning of the three phases of the second transmission line, plus the difference between the voltage at the end of the three phases of the first transmission line and the voltage at the end of the three phases of the second transmission line, by 0.5.

[0049] U' G2 =0.5×(U 1as +U 1bs +U 1cs -U 2as -U 2bs -U 2cs +U 1am +U 1bm +U 1cm -U 2am -U 2bm -U 2cm )

[0050] Among them, U′ G2 This is the second voltage modulus in the second group of voltage moduli;

[0051] The third voltage modulus in the first set of voltage moduli is obtained by multiplying the voltage difference between the beginning of phase A and phase C of the first transmission line and the voltage difference between the end of phase A and phase C of the first transmission line by 0.5.

[0052] U' L1 =0.5×(U 1as -U1cs +U 1am -U 1cm )

[0053] Among them, U′ L2 It is the third voltage modulus in the second group of voltage moduli;

[0054] The first current modulus in the second set of current moduli is obtained by subtracting the current at the end of each phase from the sum of the currents at the beginning of each phase of the double-circuit transmission line.

[0055] I' G1 =I 1as +I 1bs +I 1cs +I 2as +I 2bs +I 2cs -I 1am -I 1bm -I 1cm -I 2am -I 2bm -I 2cm

[0056] Among them, I′ G1 This is the first current modulus in the second group of current moduli;

[0057] The second current modulus in the second set of current moduli is obtained by subtracting the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line from the difference between the current at the end of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line.

[0058] I' G2 =I 1as +I 1bs +I 1cs -I 2as -I 2bs -I 2cs -(I 1am +I 1bm +I 1cm -I 2am -I 2bm -I 2cm )

[0059] Among them, I′ G2 This is the second current modulus in the second group of current moduli;

[0060] The third current modulus in the second set of current moduli is obtained by subtracting the currents at the ends of phases A and C of the first transmission line from the sum of the currents at the beginning of phases A and C of the first transmission line:

[0061] I' L1 =I 1as +I1cs -I 1am -I 1cm

[0062] Among them, I′ L2 This is the third voltage modulus in the second group of voltage moduli.

[0063] In some embodiments, the capacitance modulus of the double-circuit transmission line is calculated based on the second set of voltage moduli, the second set of current moduli, and the differential equation of the admittance of the double-circuit transmission line. Specifically, this includes the following steps:

[0064] Substituting the second set of voltage moduli and the second set of current moduli generated from the voltage and current signals acquired at different acquisition times into the differential equation of the admittance of the double-circuit transmission line, the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus are obtained by solving the differential equation of the admittance of the double-circuit transmission line:

[0065]

[0066] Where k is the index number of the sampling time, T s For the sampling period, G G1 G is the first conductivity modulus. G2 G is the second conductivity modulus. L1 The third conductivity modulus; C G1 For the first susceptance modulus, C G2 For the second susceptor modulus, C L1 This is the third susceptor modulus.

[0067] In some embodiments, the capacitor phase parameters are obtained by performing an inverse phase-mode transformation on the capacitor modulus, specifically including the following steps:

[0068] According to the inverse phase mode transformation formula, the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus are subjected to inverse phase mode transformation to obtain the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phase lines in the double-circuit transmission line, and the mutual capacitance between the transmission lines of the first circuit and the second circuit:

[0069]

[0070] Among them, C s C is the self-capacitance of the double-circuit transmission line; m C is the mutual capacitance between the three phases in the double-circuit transmission line; c This refers to the mutual capacitance between the first and second transmission lines.

[0071] In some embodiments, the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line are obtained by performing phase sequence transformation on the capacitor phase parameters, specifically including the following steps:

[0072] Based on the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phases in the double-circuit transmission line, and the mutual capacitance between the first and second transmission lines, the positive-sequence self-resistance, zero-sequence self-resistance, and zero-sequence mutual resistance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line:

[0073]

[0074] Wherein, C1 is the positive-sequence self-resistance capacitor of the double-circuit transmission line; C0 is the zero-sequence self-resistance capacitor of the double-circuit transmission line; C m The zero-sequence mutual resistance capacitance of the double-circuit transmission line is given.

[0075] Secondly, this application also provides a computer device, the computer device including a processor, a memory, and a computer program stored in the memory and executable by the processor, wherein when the computer program is executed by the processor, it implements the steps of the method for measuring parameters of a double-circuit transmission line as described above.

[0076] This application provides a method and device for measuring parameters of a double-circuit transmission line. It involves periodically acquiring voltage and current signals from the beginning and end of each phase of the double-circuit transmission line. Based on the voltage and current signals, phase-mode transformation is performed to generate two sets of voltage moduli and two sets of current moduli. The resistance and inductance moduli are calculated from the first set of moduli, and then inverse phase-mode transformation is performed to obtain the resistance and inductance phase parameters. A phase sequence transformation is then performed to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line. Similarly, the capacitance moduli of the double-circuit transmission line are calculated from the second set of moduli, and then inverse phase-mode transformation is performed to obtain the capacitance phase parameters. A phase sequence transformation is then performed to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line. This method enables simultaneous measurement of positive-sequence impedance and zero-sequence impedance and capacitive reactance parameters of the line without power outages or changes to the transmission line's operating mode. It offers high measurement accuracy and is simple and low-cost to implement. Attached Figure Description

[0077] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0078] Figure 1A flowchart illustrating a method for measuring parameters of a double-circuit transmission line provided in an embodiment of this application;

[0079] Figure 2 This is a schematic diagram of the structure of a double-circuit transmission line;

[0080] Figure 3 This is a schematic diagram of a simulation model of a double-circuit transmission line.

[0081] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0082] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0083] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0084] This application provides a method and device for measuring parameters of a double-circuit transmission line.

[0085] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0086] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating a method for measuring parameters of a double-circuit transmission line, provided as an embodiment of this application.

[0087] like Figure 1 As shown, the method includes steps S1 to S4.

[0088] Step S1: Periodically collect voltage and current signals at the beginning and end of each phase of the double-circuit transmission line.

[0089] As an example, the double-circuit transmission line in this implementation is a double-circuit parallel transmission line, and its structure is as follows: Figure 2As shown, a double-circuit transmission line includes a first transmission line and a second transmission line. Each transmission line includes three phases: A, B, and C. When collecting voltage and current signals at the beginning and end of each phase of the double-circuit transmission line, live-line measurement is employed. Current and voltage measuring devices at the beginning and end of the transmission lines are synchronized using a GPS / BeiDou navigation and timing system, thereby achieving synchronous measurement of the voltage and current signals at the beginning and end of each phase of both circuits.

[0090] The acquisition period for voltage and current signals can be customized according to requirements. In this embodiment, the acquisition period of the measuring device is T. s .

[0091] The voltage and current signals collected in each cycle at the beginning and end of each phase of the double-circuit line include: the voltage U at the beginning of phase A of the first transmission line. 1as The current I at the beginning of phase A of the first transmission line 1as The voltage U at the beginning of phase B of the first transmission line 1bs The current I at the beginning of phase B of the first transmission line 1bs The voltage U at the beginning of phase C of the first transmission line 1cs The current I at the beginning of phase C of the first transmission line 1cs The voltage U at the beginning of phase A of the second transmission line 2as The current I at the beginning of phase A of the second transmission line 2as The voltage U at the beginning of phase B of the second transmission line 2bs The current I at the beginning of phase B of the second transmission line 2bs The voltage U at the beginning of phase C of the second transmission line 2cs The current I at the beginning of phase C of the second transmission line 2cs The voltage U at the end of phase A of the first transmission line 1am The current I at the end of phase A of the first transmission line 1am The voltage U at the end of phase B of the first transmission line 1bm The current I at the end of phase B of the first transmission line 1bm The voltage U at the end of phase C of the first transmission line 1cm The current I at the end of phase C of the first transmission line 1cm The voltage U at the end of phase A of the second transmission line 2am The current I at the end of phase A of the second transmission line 2am The voltage U at the end of phase B of the second transmission line 2bm The current I at the end of phase B of the second transmission line 2bm The voltage U at the end of phase C of the second transmission line 2cm The current I at the end of phase C of the second transmission line 2cm .

[0092] After periodically acquiring voltage and current signals, the system stores each acquired signal along with the acquisition time, for example, t1 for the first sampling time, t2 for the second sampling time, and so on. After storage, an index number kx is generated based on the signal acquisition time; for example, k1 is the index number of the data related to the first sampling time, k2 is the index number of the data related to the second sampling time, and so on, with kx being the index number of the data related to the x-th sampling time.

[0093] Step S2: Perform phase-mode transformation on the voltage signal to generate a first set of voltage moduli and a second set of voltage moduli, and perform phase-mode transformation on the current signal to generate a first set of current moduli and a second set of current moduli.

[0094] Specifically, the first set of voltage moduli is generated by performing phase-mode transformation based on the voltage signal, which includes the following steps:

[0095] The first voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage at the end of each phase from the sum of the voltages at the beginning of each phase of the double-circuit transmission line.

[0096] U G1 =U 1as +U 1bs +U 1cs +U 2as +U 2bs +U 2cs -U 1am -U 1bm -U 1cm -U 2am -U 2bm -U 2cm

[0097] Among them, U G1 U is the first voltage modulus in the first group of voltage moduli. 1as U is the voltage at the beginning of phase A of the first circuit in a double-circuit transmission line. 1bs U is the voltage at the beginning of phase B of the first transmission line. 1cs U is the voltage at the beginning of phase C of the first transmission line. 2as U is the voltage at the beginning of phase A of the second circuit in a double-circuit transmission line. 2bs U is the voltage at the beginning of phase B of the second transmission line. 2cs U is the voltage at the beginning of phase C of the second transmission line. 1am U is the voltage at the end of phase A of the first transmission line. 1bm U is the voltage at the end of phase B of the first transmission line. 1cm U is the voltage at the end of phase C of the first transmission line. 2am U is the voltage at the end of phase A of the second transmission line.2bm U is the voltage at the end of phase B of the second transmission line. 2cm This refers to the voltage at the end of phase C of the second transmission line;

[0098] Next, the second voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage difference between the three-phase starting terminals of the first transmission line and the three-phase starting terminals of the second transmission line from the voltage difference between the three-phase ending terminals of the first and second transmission lines.

[0099] U G2 =U 1as +U 1bs +U 1cs -U 2as -U 2bs -U 2cs -(U 1am +U 1bm +U 1cm -U 2am -U 2bm -U 2cm )

[0100] Among them, U G2 The second voltage modulus in the first group of voltage moduli;

[0101] Then, by subtracting the voltages at the ends of phases A and C of the first transmission line from the sum of the voltages at the beginning of phases A and C of the first transmission line, the third voltage modulus in the first set of voltage moduli is obtained:

[0102] U L1 =U 1as +U 1cs -U 1am -U 1cm

[0103] Among them, U L1 It is the third voltage modulus in the first group of voltage moduli.

[0104] Furthermore, the first set of current moduli is generated by performing phase-mode transformation based on the current signal, specifically including the following steps:

[0105] The first current modulus in the first set of current moduli is obtained by multiplying the sum of the currents at the beginning and end of each phase of the double-circuit transmission line by 0.5.

[0106] I G1 =0.5×(I 1as +I 1bs +I 1cs +I 2as +I 2bs +I 2cs +I 1am +I1bm +I 1cm +I 2am +I 2bm +I 2cm )

[0107] Among them, I G1 I is the first current modulus in the first group of current moduli. 1as I is the current at the beginning of phase A of the first transmission line. 1bs I is the current at the beginning of phase B of the first transmission line. 1cs I is the current at the beginning of phase C of the first transmission line. 2as For the current at the beginning of phase A of the second transmission line, I 2bs For the current at the beginning of phase B of the second transmission line, I 2cs I is the current at the beginning of phase C of the second transmission line. 1am I is the current at the end of phase A of the first transmission line. 1bm I is the current at the end of phase B of the first transmission line. 1cm I is the current at the end of phase C of the first transmission line. 2am I is the current at the end of phase A of the second transmission line. 2bm I is the current at the end of phase B of the second transmission line. 2cm This refers to the current at the end of phase C of the second transmission line;

[0108] Next, the second current modulus in the first set of current moduli is obtained by multiplying the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line, plus the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line, by 0.5.

[0109] I G2 =0.5×(I 1as +I 1bs +I 1cs -I 2as -I 2bs -I 2cs +I 1am +I 1bm +I 1cm -I 2am -I 2bm -I 2cm )

[0110] Among them, I G2 It is the second current modulus in the first group of current moduli;

[0111] Then, by multiplying the difference in current at the beginning of phase A and phase C of the first transmission line by the difference in voltage at the end of phase A and phase C of the first transmission line, and then multiplying the result by 0.5, we obtain the third current modulus in the first set of current moduli:

[0112] I L1 =0.5×(I 1as -I 1cs +I 1am -I 1cm )

[0113] Among them, I L1 It is the third current modulus in the first group of current moduli.

[0114] Step S3: Calculate the resistance modulus and inductance modulus of the double-circuit transmission line based on the trapezoidal integral equation of the first set of voltage modulus, the first set of current modulus, and the impedance of the double-circuit transmission line. Perform inverse phase-modulus transformation on the resistance modulus and the inductance modulus to obtain the resistance phase parameters and inductance phase parameters. Perform phase-sequence transformation on the resistance phase parameters and the inductance phase parameters to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line.

[0115] Specifically, the resistance modulus and inductance modulus of the double-circuit transmission line are calculated based on the first set of voltage modulus, the first set of current modulus, and the trapezoidal integral equation of the impedance of the double-circuit transmission line. This process includes the following steps:

[0116] Substituting the voltage and current signals acquired at two adjacent acquisition times into the first set of voltage and current moduli generated, we arrive at the trapezoidal integral equation for the impedance of the double-circuit transmission line. This trapezoidal integral equation is a discretized version of the double-circuit transmission line impedance. Solving the trapezoidal integral equation for the double-circuit transmission line impedance yields the first resistance modulus, the second resistance modulus, the third resistance modulus, the first inductance modulus, the second inductance modulus, and the third inductance modulus.

[0117]

[0118] Where t1 is the first acquisition time, t2 is the second sampling time, t1 and t2 are two adjacent acquisition times, and T S Sampling period T s =t2-t1, R G1 R is the first resistive modulus. G2 R is the second resistive modulus. L1 The third resistive modulus; L G1 L is the first inductance modulus. G2 L is the second inductance modulus. L1 This is the third inductance modulus.

[0119] In the calculation, based on the current and voltage collected at time t1, the first set of voltage moduli and the first set of current moduli corresponding to time t1 are calculated. Based on the current and voltage collected at time t2, the first set of voltage moduli and the first set of current moduli corresponding to time t2 are calculated. Substituting the first set of voltage moduli and the first set of current moduli corresponding to time t1 and t2 into the trapezoidal integral equation of the impedance of the double-circuit transmission line, the R can be solved. G1 R G2 R L1 L G1 L G2 and L L1 .

[0120] Furthermore, the phase-mode inverse transformation of the resistance modulus and the inductance modulus is performed to obtain the resistance phase parameters and the inductance phase parameters, specifically including the following steps:

[0121] According to the inverse phase-mode transformation formula, the first resistance modulus, the second resistance modulus, the third resistance modulus, the first inductance modulus, the second inductance modulus, and the third inductance modulus are subjected to inverse phase-mode transformation to obtain the self-resistance of the double-circuit transmission line, the mutual resistance between the three phase lines in the double-circuit transmission line, the mutual resistance between the transmission lines of the first circuit and the second circuit, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phase lines in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first circuit and the second circuit:

[0122]

[0123]

[0124] Among them, R s R is the self-resistance of the double-circuit transmission line. m R is the mutual resistance between the three phases in the double-circuit transmission line. c L is the mutual resistance between the first transmission line and the second transmission line. s L is the self-inductance of the double-circuit transmission line. m L is the mutual inductance between the three phases in the double-circuit transmission line. c The mutual inductance between the first transmission line and the second transmission line is denoted as .

[0125] Furthermore, the phase sequence transformation of the resistive phase parameters and the inductive phase parameters is performed to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line, specifically including the following steps:

[0126] Based on the self-resistance of the double-circuit transmission line, the mutual resistance between the three phases in the double-circuit transmission line, the mutual resistance between the transmission lines of the first and second circuits, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phases in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first and second circuits, the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line.

[0127]

[0128] Where Z1 is the positive-sequence self-impedance of the double-circuit transmission line; Z0 is the zero-sequence self-impedance of the double-circuit transmission line; Z m Let jωL be the zero-sequence mutual impedance of the double-circuit transmission line, j be the imaginary unit in the electrical field, ω be the angular velocity, ω = 2πf, f be the system frequency (typically 50Hz), and jωL be the impedance parameter.

[0129] Step S2, performing phase-mode transformation on the voltage signal to generate a first set of voltage moduli and a second set of voltage moduli, and performing phase-mode transformation on the current signal to generate a first set of current moduli and a second set of current moduli, specifically further includes:

[0130] The process involves performing phase-mode transformation on the voltage signal to generate a second set of voltage moduli, and performing phase-mode transformation on the current signal to generate a second set of current moduli. Specifically, this includes the following steps:

[0131] The first voltage modulus in the second set of voltage moduli is obtained by multiplying the sum of the voltages at the beginning and end of each phase of the double-circuit transmission line by 0.5.

[0132] U' G1 =0.5×(U 1as +U 1bs +U 1cs +U 2as +U 2bs +U 2cs +U 1am +U 1bm +U 1cm +U 2am +U 2bm +U 2cm )

[0133] Among them, U′ G1 This is the first voltage modulus in the second group of voltage moduli;

[0134] Next, the second voltage modulus in the first set of voltage moduli is obtained by multiplying the difference between the voltage at the beginning of the three phases of the first transmission line and the voltage at the beginning of the three phases of the second transmission line, plus the difference between the voltage at the end of the three phases of the first transmission line and the voltage at the end of the three phases of the second transmission line, by 0.5.

[0135] U' G2 =0.5×(U 1as +U 1bs +U 1cs -U 2as -U 2bs -U 2cs +U 1am +U 1bm +U 1cm -U 2am -U 2bm -U 2cm )

[0136] Among them, U′ G2 This is the second voltage modulus in the second group of voltage moduli;

[0137] Then, by multiplying the voltage difference between the beginning terminals of phase A and phase C of the first transmission line and the voltage difference between the ends terminals of phase A and phase C of the first transmission line by 0.5, the third voltage modulus in the first set of voltage moduli is obtained:

[0138] U' L1 =0.5×(U 1as -U 1cs +U 1am -U 1cm )

[0139] Among them, U′ L2 It is the third voltage modulus in the second group of voltage moduli;

[0140] Furthermore, the first current modulus in the second set of current moduli is obtained by subtracting the current at the end of each phase from the sum of the currents at the beginning of each phase of the double-circuit transmission line:

[0141] I' G1 =I 1as +I 1bs +I 1cs +I 2as +I 2bs +I 2cs -I 1am -I 1bm -I 1cm -I 2am -I 2bm -I 2cm

[0142] Among them, I′ G1This is the first current modulus in the second group of current moduli;

[0143] Next, the second current modulus in the second set of current moduli is obtained by subtracting the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line from the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line.

[0144] I' G2 =I 1as +I 1bs +I 1cs -I 2as -I 2bs -I 2cs -(I 1am +I 1bm +I 1cm -I 2am -I 2bm -I 2cm )

[0145] Among them, I′ G2 This is the second current modulus in the second group of current moduli;

[0146] Then, by subtracting the currents at the ends of phases A and C of the first transmission line from the sum of the currents at the beginning of phases A and C of the first transmission line, we obtain the third current modulus in the second set of current moduli:

[0147] I' L1 =I 1as +I 1cs -I 1am -I 1cm

[0148] Among them, I′ L2 This is the third voltage modulus in the second group of voltage moduli.

[0149] Step S4: Calculate the capacitance modulus of the double-circuit transmission line based on the second set of voltage modulus, the second set of current modulus, and the differential equation of the admittance of the double-circuit transmission line. Perform an inverse phase-mode transformation on the capacitance modulus to obtain the capacitance phase parameters. Perform a phase-sequence transformation on the capacitance phase parameters to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line.

[0150] Specifically, the capacitance modulus of the double-circuit transmission line is calculated based on the second set of voltage moduli, the second set of current moduli, and the differential equation of the admittance of the double-circuit transmission line. This calculation includes the following steps:

[0151] Substituting the second set of voltage moduli and the second set of current moduli generated from the voltage and current signals acquired at different acquisition times into the differential equation of the admittance of the double-circuit transmission line, wherein the differential equation of the admittance of the double-circuit transmission line is a discretized differential equation form of the admittance of the double-circuit transmission line. Solving the differential equation of the admittance of the double-circuit transmission line yields the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus:

[0152]

[0153] Where k is the index number of the sampling time, T s For the sampling period, G G1 G is the first conductivity modulus. G2 G is the second conductivity modulus. L1 The third conductivity modulus; C G1 For the first susceptance modulus, C G2 For the second susceptor modulus, C L1 Let G be the third susceptance modulus. Substituting the second set of voltage moduli and the second set of current moduli corresponding to the three sampling times into the differential equation for the admittance of a double-circuit transmission line, we can solve for G. G1 G G2 G L1 C G1 C G2 and C L1 .

[0154] Furthermore, according to the inverse phase-mode transformation formula, the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus are subjected to inverse phase-mode transformation to obtain the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phase lines in the double-circuit transmission line, and the mutual capacitance between the transmission lines of the first circuit and the second circuit:

[0155]

[0156] Among them, C s C is the self-capacitance of the double-circuit transmission line; m C is the mutual capacitance between the three phases in the double-circuit transmission line; c This refers to the mutual capacitance between the first and second transmission lines.

[0157] Furthermore, the phase sequence transformation of the capacitor phase parameters is performed to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line, specifically including the following steps:

[0158] Based on the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phases in the double-circuit transmission line, and the mutual capacitance between the first and second transmission lines, the positive-sequence self-resistance, zero-sequence self-resistance, and zero-sequence mutual resistance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line:

[0159]

[0160] Wherein, C1 is the positive-sequence self-resistance capacitor of the double-circuit transmission line; C0 is the zero-sequence self-resistance capacitor of the double-circuit transmission line; C m The zero-sequence mutual resistance capacitance of the double-circuit transmission line is given.

[0161] In one embodiment, the measurement method for double-circuit transmission line parameters of this application is used to simulate a double-circuit parallel transmission line with a length varying from 30km to 100km. (According to the appendix...) Figure 1 The physical model of the double-circuit parallel transmission line shown is established in the electromagnetic transient simulation software PSCAD as follows. Figure 3 The simulation model shown.

[0162] The theoretical values ​​per unit length for a double-circuit transmission line are shown in Table 1.

[0163] Table 1 Theoretical values ​​of various parameters for double-circuit transmission lines

[0164]

[0165] The measurement results obtained according to the measurement method of this application are shown in Table 2.

[0166] Table 2. Measurement results of various parameters of the double-circuit line obtained according to the method of the present invention.

[0167]

[0168] A comparative analysis of Tables 1 and 2 leads to the following conclusions:

[0169] (1) When the double-circuit transmission line is relatively short, i.e., when a lumped parameter model can be used, it is feasible to use the phase mode transformation method to simultaneously obtain the positive sequence parameters and zero sequence parameters of the double-circuit line. (2) It is feasible to use a differential equation model to solve the sequence parameters of the double-circuit line, and the measurement error is minimally affected by the change in line length.

[0170] The measurement method for double-circuit transmission line parameters in this application is applicable to short-distance double-circuit transmission lines of any voltage level. Furthermore, this application utilizes GPS / North Navigation technology to solve the problem of simultaneous measurement of signals from different locations. This application only requires periodically collecting voltage and current signals from the beginning and end of each phase of the double-circuit transmission line while it is energized to simultaneously determine multiple line parameters, including positive-sequence resistance, positive-sequence inductance, positive-sequence capacitance, zero-sequence resistance, zero-sequence inductance, and zero-sequence capacitance, with high measurement accuracy. It achieves simultaneous measurement of positive-sequence impedance and zero-sequence impedance and capacitive reactance parameters without power outages or changes to the transmission line's operating mode, offering high measurement accuracy and simple, low-cost implementation.

[0171] The method for measuring parameters of a double-circuit transmission line provided in the above embodiments can be implemented in a computer device as a computer program, which can run on the computer device. The computer device can be a terminal.

[0172] It should be noted that those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the computer device described above can be referred to the corresponding process in the foregoing embodiments, and will not be repeated here.

[0173] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0174] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above descriptions are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for measuring parameters of a double-circuit transmission line, characterized in that, include: Periodically collect voltage and current signals at the beginning and end of each phase of the double-circuit transmission line; A first set of voltage moduli and a second set of voltage moduli are generated by performing phase mode transformation on the voltage signal, and a first set of current moduli and a second set of current moduli are generated by performing phase mode transformation on the current signal. The resistance modulus and inductance modulus of the double-circuit transmission line are calculated based on the trapezoidal integral equation of the first set of voltage modulus, the first set of current modulus, and the impedance of the double-circuit transmission line. The phase modulus and inductance modulus are then subjected to inverse phase-modulus transformation to obtain the phase parameters of resistance and inductance. The phase sequence transformation of the phase parameters of resistance and inductance is then performed to obtain the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line. The capacitance modulus of the double-circuit transmission line is calculated based on the differential equations of the second set of voltage modulus, the second set of current modulus, and the admittance of the double-circuit transmission line. The capacitance modulus is then subjected to inverse phase-mode transformation to obtain the capacitance phase parameters. Finally, the capacitance phase parameters are subjected to phase-sequence transformation to obtain the positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line. The first voltage modulus in the first group of voltage moduli is obtained by subtracting the voltage at the end of each phase from the sum of the voltages at the beginning of each phase of the double-circuit transmission line. The second voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage difference between the three-phase starting terminals of the first transmission line and the three-phase starting terminals of the second transmission line from the voltage difference between the three-phase ending terminals of the first transmission line and the three-phase ending terminals of the second transmission line. The third voltage modulus in the first set of voltage moduli is obtained by subtracting the voltages at the ends of phases A and C of the first transmission line from the sum of the voltages at the beginning of phases A and C of the first transmission line. The first current modulus in the first group of current moduli is obtained by multiplying the sum of the current at the beginning and end of each phase of the double-circuit transmission line by 0.

5. The second current modulus in the first set of current moduli is obtained by multiplying the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line, plus the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line, by 0.

5. The third current modulus in the first set of current moduli is obtained by multiplying the difference in current at the beginning of phase A and phase C of the first transmission line by 0.5 and adding the difference in voltage at the end of phase A and phase C of the first transmission line.

2. The method for measuring parameters of a double-circuit transmission line according to claim 1, characterized in that, The first voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage at the end of each phase from the sum of the voltages at the beginning of each phase of the double-circuit transmission line. This includes: in, This refers to the first voltage modulus in the first group of voltage moduli. This refers to the voltage at the beginning of phase A of the first circuit in a double-circuit transmission line. This refers to the voltage at the beginning of phase B of the first transmission line. This refers to the voltage at the beginning of phase C of the first transmission line. This refers to the voltage at the beginning of phase A of the second circuit in a double-circuit transmission line. This refers to the voltage at the beginning of phase B of the second transmission line. This refers to the voltage at the beginning of phase C of the second transmission line. This is the voltage at the end of phase A of the first transmission line. This refers to the voltage at the end of phase B of the first transmission line. This refers to the voltage at the end of phase C of the first transmission line. This refers to the voltage at the end of phase A of the second transmission line. This refers to the voltage at the end of phase B of the second transmission line. This refers to the voltage at the end of phase C of the second transmission line; The second voltage modulus in the first set of voltage moduli is obtained by subtracting the voltage difference between the three-phase starting terminals of the first and second transmission lines from the voltage difference between the three-phase starting terminals of the first and second transmission lines. in, This refers to the second voltage modulus in the first group of voltage moduli; The third voltage modulus in the first set of voltage moduli is obtained by subtracting the voltages at the ends of phases A and C of the first transmission line from the sum of the voltages at the beginning of phases A and C of the first transmission line. in, It is the third voltage modulus in the first group of voltage moduli; The first current modulus in the first set of current moduli is obtained by multiplying the sum of the currents at the beginning and end of each phase of the double-circuit transmission line by 0.

5. in, This refers to the first current modulus in the first group of current moduli. This refers to the current at the beginning of phase A of the first transmission line. This refers to the current at the beginning of phase B of the first transmission line. This refers to the current at the beginning of phase C of the first transmission line. This refers to the current at the beginning of phase A of the second transmission line. This refers to the current at the beginning of phase B of the second transmission line. This refers to the current at the beginning of phase C of the second transmission line. This refers to the current at the end of phase A of the first transmission line. This refers to the current at the end of phase B of the first transmission line. This refers to the current at the end of phase C of the first transmission line. This refers to the current at the end of phase A of the second transmission line. This refers to the current at the end of phase B of the second transmission line. This refers to the current at the end of phase C of the second transmission line; The second current modulus in the first set of current moduli is obtained by multiplying the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line, plus the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line, by 0.

5. in, It is the second current modulus in the first group of current moduli; The third current modulus in the first set of current moduli is obtained by multiplying the difference in current at the beginning of phase A and phase C of the first transmission line by the difference in voltage at the end of phase A and phase C of the first transmission line, and then multiplying the result by 0.

5. in, It is the third current modulus in the first group of current moduli.

3. The method for measuring parameters of a double-circuit transmission line according to claim 2, characterized in that, The resistance modulus and inductance modulus of the double-circuit transmission line are calculated based on the first set of voltage modulus, the first set of current modulus, and the trapezoidal integral equation of the impedance of the double-circuit transmission line. Specifically, this includes the following steps: Substituting the voltage and current signals acquired at two adjacent acquisition times into the first set of voltage moduli and the first set of current moduli generated, we obtain the first resistance moduli, the second resistance moduli, the third resistance moduli, the first inductance moduli, the second inductance moduli, and the third inductance moduli by solving the trapezoidal integral equation of the double-circuit transmission line impedance: in, This is the first data collection moment. For the second sampling set time, and For two adjacent data acquisition times, Sampling period , The first resistive modulus, The second resistive modulus, It is the third resistive modulus; The first inductance modulus, The second inductance modulus, This is the third inductance modulus.

4. The method for measuring parameters of a double-circuit transmission line according to claim 3, characterized in that, The inverse phase-mode transformation of the resistance modulus and the inductance modulus yields the resistance phase parameters and inductance phase parameters, specifically including the following steps: According to the inverse phase-mode transformation formula, the first resistance modulus, the second resistance modulus, the third resistance modulus, the first inductance modulus, the second inductance modulus, and the third inductance modulus are subjected to inverse phase-mode transformation to obtain the self-resistance of the double-circuit transmission line, the mutual resistance between the three phase lines in the double-circuit transmission line, the mutual resistance between the transmission lines of the first circuit and the second circuit, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phase lines in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first circuit and the second circuit: in, The self-resistance of the double-circuit transmission line is... The mutual resistance between the three phases in the double-circuit transmission line. The mutual resistance between the first and second transmission lines is given. The self-inductance of the aforementioned double-circuit transmission line, The mutual inductance between the three phases in the double-circuit transmission line is... The mutual inductance between the first transmission line and the second transmission line is denoted as .

5. The method for measuring parameters of a double-circuit transmission line according to claim 4, characterized in that, The positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line are obtained by performing phase sequence transformation on the resistive phase parameters and the inductive phase parameters, specifically including the following steps: Based on the self-resistance of the double-circuit transmission line, the mutual resistance between the three phases in the double-circuit transmission line, the mutual resistance between the transmission lines of the first and second circuits, the self-inductance of the double-circuit transmission line, the mutual inductance between the three phases in the double-circuit transmission line, and the mutual inductance between the transmission lines of the first and second circuits, the positive-sequence self-impedance, zero-sequence self-impedance, and zero-sequence mutual impedance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line. in, The positive sequence self-impedance of the double-circuit transmission line; The zero-sequence self-impedance of the double-circuit transmission line; The zero-sequence mutual impedance of the double-circuit transmission line is... ω is the imaginary unit, and ω is the angular velocity.

6. The method for measuring parameters of a double-circuit transmission line according to claim 1, characterized in that, The process involves performing phase-mode transformation on the voltage signal to generate a second set of voltage moduli, and performing phase-mode transformation on the current signal to generate a second set of current moduli. Specifically, this includes the following steps: The first voltage modulus in the second set of voltage moduli is obtained by multiplying the sum of the voltages at the beginning and end of each phase of the double-circuit transmission line by 0.

5. in, This is the first voltage modulus in the second group of voltage moduli; The second voltage modulus in the second set of voltage moduli is obtained by multiplying the difference between the voltage at the beginning of the three phases of the first transmission line and the voltage at the beginning of the three phases of the second transmission line, plus the difference between the voltage at the end of the three phases of the first transmission line and the voltage at the end of the three phases of the second transmission line, by 0.

5. in, This is the second voltage modulus in the second group of voltage moduli; The third voltage modulus in the second set of voltage moduli is obtained by multiplying the voltage difference between the beginning and end voltages of phases A and C of the first transmission line by 0.

5. in, It is the third voltage modulus in the second group of voltage moduli; The first current modulus in the second set of current moduli is obtained by subtracting the current at the end of each phase from the sum of the currents at the beginning of each phase of the double-circuit transmission line. in, This is the first current modulus in the second group of current moduli; The second current modulus in the second set of current moduli is obtained by subtracting the difference between the current at the beginning of the three phases of the first transmission line and the current at the beginning of the three phases of the second transmission line from the difference between the current at the end of the three phases of the first transmission line and the current at the end of the three phases of the second transmission line. in, This is the second current modulus in the second group of current moduli; The third current modulus in the second set of current moduli is obtained by subtracting the currents at the ends of phases A and C of the first transmission line from the sum of the currents at the beginning of phases A and C of the first transmission line: in, This is the third voltage modulus in the second group of voltage moduli.

7. The method for measuring parameters of a double-circuit transmission line according to claim 6, characterized in that, The capacitance modulus of the double-circuit transmission line is calculated based on the second set of voltage moduli, the second set of current moduli, and the differential equation of the admittance of the double-circuit transmission line. This calculation specifically includes the following steps: Substituting the second set of voltage moduli and the second set of current moduli generated from the voltage and current signals acquired at different acquisition times into the differential equation of the admittance of the double-circuit transmission line, the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus are obtained by solving the differential equation of the admittance of the double-circuit transmission line: in, This is the index number of the sampling time. The sampling period is The first conductivity modulus, The second conductivity modulus, It is the third conductivity modulus; The first susceptor modulus, The second electric susceptor modulus, This is the third susceptor modulus.

8. The method for measuring parameters of a double-circuit transmission line according to claim 7, characterized in that, The capacitor phase parameters are obtained by performing an inverse phase-mode transformation on the capacitor modulus, specifically including the following steps: According to the inverse phase mode transformation formula, the first susceptance modulus, the second susceptance modulus, and the third susceptance modulus are subjected to inverse phase mode transformation to obtain the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phase lines in the double-circuit transmission line, and the mutual capacitance between the transmission lines of the first circuit and the second circuit: in, The self-capacitance of the double-circuit transmission line; The mutual capacitance between the three phases in the double-circuit transmission line; This refers to the mutual capacitance between the first and second transmission lines.

9. The method for measuring parameters of a double-circuit transmission line according to claim 8, characterized in that, The positive-sequence self-capacitance, zero-sequence self-capacitance, and zero-sequence mutual capacitance of the double-circuit transmission line are obtained by performing phase sequence transformation on the capacitor phase parameters, specifically including the following steps: Based on the self-capacitance of the double-circuit transmission line, the mutual capacitance between the three phases in the double-circuit transmission line, and the mutual capacitance between the first and second transmission lines, the positive-sequence self-resistance, zero-sequence self-resistance, and zero-sequence mutual resistance of the double-circuit transmission line are calculated using the phase sequence transformation formula for a fully transposed line: in, The positive sequence self-resistance capacitor of the double-circuit transmission line; The zero-sequence self-resistance capacitor of the double-circuit transmission line; The zero-sequence mutual resistance capacitance of the double-circuit transmission line is given.

10. A computer device, characterized in that, The computer device includes a processor, a memory, and a computer program stored in the memory and executable by the processor, wherein when the computer program is executed by the processor, it implements the steps of the method for measuring parameters of a double-circuit transmission line as described in any one of claims 1 to 9.

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