CN117805555A - Two-way deduction four-terminal flexible direct current transmission line fault location method and system - Google Patents
Two-way deduction four-terminal flexible direct current transmission line fault location method and system Download PDFInfo
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- CN117805555A CN117805555A CN202410219452.2A CN202410219452A CN117805555A CN 117805555 A CN117805555 A CN 117805555A CN 202410219452 A CN202410219452 A CN 202410219452A CN 117805555 A CN117805555 A CN 117805555A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/085—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution lines, e.g. overhead
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/088—Aspects of digital computing
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- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
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Abstract
The invention relates to a fault location method and system for a two-way deduction four-terminal flexible direct current transmission line, and belongs to the technical field of relay protection of power systems. The invention utilizes the fault voltage traveling wave sequence to construct a circular left shift matrix and a circular right shift matrix, calculates the product of the two matrices, sums each row of the product matrix, and the distance corresponding to the row with the minimum value is the fault distance. Compared with time domain traveling wave single-end ranging, the ranging method breaks through the bottleneck of calibrating traveling wave arrival time in the time domain, is easy to realize automatic single-end traveling wave ranging of the grounding electrode line, and avoids errors caused by unreliable wave head identification and inaccurate arrival time calibration.
Description
Technical Field
The invention relates to a fault location method and system for a two-way deduction four-terminal flexible direct current transmission line, and belongs to the field of relay protection of power systems.
Background
With the increase of the distance of the direct current transmission line and the expansion of the power grid, higher requirements are put forward on the safety and reliability of the operation control of the complex power grid, and the accurate positioning of the fault of the transmission line in the power grid has become more and more important. The existing fault distance measurement technology cannot meet the requirements of intelligent protection and positioning of a wide area network, and compared with various distance measurement methods, the traveling wave distance measurement technology has obvious theoretical advantages, because the traveling wave distance measurement technology is not affected by factors such as distributed capacitance, system oscillation and current transformer saturation. The traditional distance measuring method based on the traveling wave heads at the two ends of the line is not influenced by various reflected waves and refracted waves, the principle is relatively simple, and only the information of the initial wave heads reaching the two ends of the line needs to be captured. However, this method is greatly affected by the operating conditions of the positioning device and the interference signals. The traditional single-end distance measurement method needs to calibrate an initial wave head and a second wave head, traveling wave signals propagate at the speed of light, the traveling wave signals are slightly and immediately passed, the propagation path is complex, and the single-end traveling wave distance measurement method is required to be improved because the single-end traveling wave distance measurement method cannot be practically applied on site due to the influence of large electromagnetic interference of the field environment, obvious electromagnetic oscillation of line lightning stroke, stray capacitance of a bus and the like.
Disclosure of Invention
The invention provides a fault distance measurement method and system for a four-terminal flexible direct current transmission line, which break through the technical bottleneck of representing traveling wave singularities by using a signal processing method in the past, are not dependent on detection of fault point reflected waves in a time domain, have strong anti-interference capability, are not influenced by a system operation mode, and avoid errors caused by unreliable wave head identification and inaccurate wave arrival time calibration.
The technical scheme of the invention is as follows: four-terminal flexible direct current deduced in two directionsAccording to the fault location method of the power transmission line, when the line breaks down, the line capacitance discharges through impedance, energy stored along an electric field and a magnetic field of the line is converted into fault current traveling waves and corresponding voltage traveling waves, and as smoothing reactors are arranged on two sides of the line, negative total reflection occurs on the current traveling waves, and the current traveling waves are zero, the voltage traveling waves are used as electric quantity of fault location. The expression of the fault voltage head isWhereinβ Mu Representing the reflection coefficient at the traveling wave coupling box,xindicating the location of the fault,vthe wave velocity of the traveling wave is represented,u f (t－x/v) Representing a voltage traveling wave propagating from the fault point to the traveling wave coupling box; the second wave head expression isWhereinβ fu Representing the reflection coefficient of the fault point; the third wave head expression isWhereinα fu Representing the index of refraction of the fault point. The head of the head wave slides along the positive direction of the time axisIn the time-width of the time-frame,the second wave head slides along the negative direction of the time axisIn the time-width of the time-frame,whereinLIs the full length of the line. When the first and second sliding wave heads are coincident, i.eIn the time-course of which the first and second contact surfaces,the point is a failure point.
The method comprises the following specific steps:
step1: and acquiring fault voltage traveling wave data by using the traveling wave coupling box, and acquiring a fault characteristic enhancement signal.
Step1.1: the fault voltage traveling wave signals of the line are collected by using a traveling wave coupling box; because both ends of the high-voltage direct-current transmission line are generally provided with smoothing reactors for current limiting and filtering, when the frequency of a signal on the line is higher, the boundary presents larger impedance characteristics, which is equivalent to an open circuit, and no current traveling wave can be detected. According to the following:
infinitely long right angle incident wave u q 、i q Along wave impedance z 1 And z 2 The two lines of (a) propagate forward, then the reflected voltage wave u f And a reflected current wave i f The expression of (2) is:
when the line ends are open, i.e. equivalent to connecting a z-line at the ends 2 A line of +.. Therefore, no current traveling wave exists at the measuring point, and the voltage traveling wave is collected for subsequent analysis.
The reason that the traveling wave coupling box is used for collecting the voltage traveling wave is that the capability of the voltage transformer for transmitting high-frequency signals is poor, the voltage transformer is not used for measuring the voltage traveling wave, the traveling wave coupling box is arranged at a measuring point, a current signal is generated after the fault voltage traveling wave passes through the traveling wave coupling box, and the current signal is measured by the current transformer, so that the voltage signal is indirectly measured.
Step1.2: and decoupling the fault voltage traveling wave signal by using a line mode transformation matrix to obtain a line mode voltage traveling wave. Because the transmission line in the high-voltage direct-current transmission system is longer, electromagnetic coupling exists between the positive electrode and the negative electrode of the transmission line, and the line voltage and the line current are very difficult to solve, so that the fault voltage traveling wave needs to be decoupled to separate positive and negative voltages into independent line mode components and zero mode components. The decoupled 0-mode component and 1-mode component do not couple to each other during propagation, and each modulus is similar to a monopolar transmission line. Because the zero-mode electric quantity is seriously attenuated in the propagation process, and the zero-mode components are equal in size and same in polarity on the two transmission lines, the zero-mode components and the earth form loops in practice, so that the zero-mode components only exist under the condition that the line has a ground fault, and the line-mode components form loops between two electrode lines, so that the zero-mode electric quantity is more suitable for analysis of different fault types due to the fact that the line-mode components and the ground fault are in existence and the interelectrode fault are also in existence.
Step1.3: and carrying out first-order differential transformation on the line mode voltage traveling wave, eliminating sampling values with smaller variation and reducing interference.
Step2: and constructing a circular right shift matrix and a circular left shift matrix by using the voltage traveling wave data. A series of forward voltage traveling wave and reverse voltage traveling wave are constructed on the line, and the constructed voltage traveling wave is used for matching the real fault voltage traveling wave.
Step2.1: setting the number m of data points moved each time and the number n of times moved each time;
the number of data points per movement:
wherein f s For sampling frequency, l x V is the wave velocity, which is the distance step of the movement.
The number of movements:
where l is the line length.
Step2.2: after the voltage traveling wave sequence moves rightwards by m sampling points, moving the last m sampling points to the head end of the whole sequence to form a first row of a circular right-shift matrix, and circulating the voltage traveling wave sequence until the set moving times n are reached to form a circular right-shift matrix P;
in the matrix P, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular right shift matrix is n rows and k columns.
Step2.3: after the voltage traveling wave sequence moves leftwards by m sampling points, the m sampling points at the head end are moved to the tail end of the whole sequence to form a first row of a circular left shift matrix, and the voltage traveling wave sequence is circulated until the set movement times n are reached to form a circular left shift matrix Q;
in the matrix Q, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular left shift matrix is n rows and k columns.
Step3: and calculating the product of the cyclic right shift matrix and the cyclic left shift matrix to obtain a product matrix R. The product of the matrices after each shift is used to reflect the mutation of the traveling wave sequence at each distance point on the line. Since the matrices P and Q are homonymous matrices, the multiplication of the homonymous matrices cannot be achieved by conventional matrix multiplication, where the hadamard Ma Chengji of the matrices is used to implement the product operation of the homonymous matrices.
Step4: and summing each row of the product matrix to obtain S (n), wherein the distance corresponding to the row with the smallest sum value is the fault distance. The abrupt change degree of the traveling wave sequence in Step3 is further enhanced, and the sum value is negative because the initial wave head of the fault voltage and the wave head of the fault point reflected wave have opposite polarities, so that the distance corresponding to the row with the smallest sum value is the fault distance. The expression of S (n) is:
if the value of the ith row is the smallest in the S matrix, the distance corresponding to the ith row is the fault distance.
A two-way deduced four-terminal flexible direct current transmission line fault location system comprises:
the electric signal acquisition module is used for acquiring and storing fault voltage traveling wave data;
the numerical value calculation module is used for calculating the row sum of the cyclic right shift matrix, the cyclic left shift matrix and the product matrix;
the fault distance measuring module is used for calibrating the distance corresponding to the row with the minimum value and recording the distance measuring result.
The electrical signal acquisition module comprises:
the data acquisition unit is used for acquiring analog signals output by the secondary side of the transformer;
the analog-to-digital conversion unit is used for converting the analog signal into a digital signal;
and the protection starting unit is used for judging whether the digital signal is larger than a set starting threshold value, and if so, reading the starting time and storing the data.
The numerical calculation module includes:
the line-mode conversion unit is used for calculating the line-mode component of the voltage traveling wave of the measuring end;
the parameter setting unit is used for setting the moving distance step length, the length of the power transmission line and the sampling frequency;
and the numerical value calculation unit is used for calculating a cyclic right shift matrix, a cyclic left shift matrix and a row sum of the cyclic right shift matrix and the cyclic left shift matrix and the product matrix.
The fault location module includes:
the amplitude calibration unit is used for calibrating the point with the minimum sum value;
and the ranging result recording unit is used for recording the ranging result.
The beneficial effects of the invention are as follows:
1. the invention breaks through the technical bottleneck of representing the traveling wave singularity by using a signal processing method in the past.
2. The invention does not rely on detection of fault point reflected waves in the time domain.
3. The invention has strong anti-interference capability and is not influenced by the running mode of the system.
4. The method avoids errors caused by unreliable wave head identification and inaccurate wave arrival time calibration.
Drawings
FIG. 1 is a topology of a simulation model of the present invention;
fig. 2 is a diagram of ranging results according to embodiment 1 of the present invention;
fig. 3 is a diagram of ranging results according to embodiment 2 of the present invention.
Detailed Description
The invention will be further described with reference to the drawings and detailed description.
Example 1: the simulation model system of the four-terminal flexible direct current power grid is shown in figure 1, wherein the total length of a line 1 is 210km, the total length of a line 2 is 50.9km, the total length of a line 3 is 208km, the total length of a line 4 is 190km, and the voltage class is +/-500 kV. The fault is set to occur at 5.09km of line 2, the fault type is set to be a permanent fault of positive ground, the transition resistance is set to be 0.01Ω, and the sampling rate is 500kHz. The implementation method comprises the following specific steps:
step1: and acquiring fault voltage traveling wave data by using the traveling wave coupling box, and acquiring a fault characteristic enhancement signal.
Step1.1: the fault voltage traveling wave signals of the line are collected by using a traveling wave coupling box;
step1.2: decoupling the fault traveling wave signal by using a line mode transformation matrix to obtain a line mode voltage traveling wave;
step1.3: and carrying out first-order differential transformation on the line mode voltage traveling wave.
Step2: and constructing a circular right shift matrix and a circular left shift matrix by using the voltage traveling wave data.
Step2.1: setting the number m of data points moved each time and the number n of times moved each time;
the number of data points per movement:
wherein f s For sampling frequency, l x V is the wave velocity, which is the distance step of the movement. In the present embodiment, f s 500kHz, l x Taking 0.01km and wave speed 300km/ms.
The number of movements:
where l is the line length. In this embodiment, where l is 50.9km, the number of movements n is 5090.
Step2.2: after the voltage traveling wave sequence moves rightwards by m sampling points, moving the last m sampling points to the head end of the whole sequence to form a first row of a circular right-shift matrix, and circulating the voltage traveling wave sequence until the set moving times n are reached to form a circular right-shift matrix P;
in the matrix P, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular right shift matrix is n rows and k columns. In the present embodiment, the number k of sampling points is 170.
Step2.3: after the voltage traveling wave sequence moves leftwards by m sampling points, the m sampling points at the head end are moved to the tail end of the whole sequence to form a first row of a cyclic leftwards movement matrix, and the voltage traveling wave sequence is circulated until the set movement times n are reached to form a cyclic leftwards movement matrix Q;
in the matrix Q, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular left shift matrix is n rows and k columns. In the present embodiment, the number k of sampling points is 170.
Step3: and calculating the product of the cyclic right shift matrix and the cyclic left shift matrix to obtain a product matrix R. Since the matrices P and Q are homonymous matrices, the multiplication of the homonymous matrices cannot be achieved by conventional matrix multiplication, where the hadamard Ma Chengji of the matrices is used to implement the product operation of the homonymous matrices.
Step4: and summing each row of the product matrix to obtain S (n), wherein the distance corresponding to the row with the smallest sum value is the fault distance. The expression of S (n) is:
if the value of the ith row is the smallest in the S matrix, the distance corresponding to the ith row is the fault distance. In this embodiment, the minimum value is obtained at line 505: 5.863X 10 46 Due to the movement step l x Taking 0.01km, i.e., 0.01km for each row in the cyclic matrix, the fault distance is 505×0.01=5.05 km. The ranging result is shown in fig. 2, and the ranging error is: 5.09-5.05=0.04 km, the range error is small.
A two-way deduced four-terminal flexible direct current transmission line fault location system comprises:
the electric signal acquisition module is used for acquiring and storing fault voltage traveling wave data;
the numerical value calculation module is used for calculating the row sum of the cyclic right shift matrix, the cyclic left shift matrix and the product matrix;
the fault distance measuring module is used for calibrating the distance corresponding to the row with the minimum value and recording the distance measuring result.
The electrical signal acquisition module comprises:
the data acquisition unit is used for acquiring analog signals output by the secondary side of the transformer;
the analog-to-digital conversion unit is used for converting the analog signal into a digital signal;
and the protection starting unit is used for judging whether the digital signal is larger than a set starting threshold value, and if so, reading the starting time and storing the data.
The numerical calculation module includes:
the line-mode conversion unit is used for calculating the line-mode component of the voltage traveling wave of the measuring end;
and the parameter setting unit is used for setting the moving distance step length, the power transmission line length and the sampling frequency. In this embodiment, the moving step length is 0.01km, the transmission line length is 50.9km, and the sampling frequency is 500kHz.
And the numerical value calculation unit is used for calculating a cyclic right shift matrix, a cyclic left shift matrix and a row sum of the cyclic right shift matrix and the cyclic left shift matrix and the product matrix.
The fault location module includes:
and the amplitude calibration unit is used for calibrating the point with the minimum sum value. Line 505 of the row with the smallest sum, value-5.863 ×10 46 。
And the ranging result recording unit is used for recording the ranging result. The ranging result was 5.05km.
Example 2: the simulation model system of the four-terminal flexible direct current power grid is shown in figure 1, wherein the total length of a line 1 is 210km, the total length of a line 2 is 50.9km, the total length of a line 3 is 208km, the total length of a line 4 is 190km, and the voltage class is +/-500 kV. The fault is set to occur at 52km of line 3, the fault type is set to be a permanent fault of positive ground, the transition resistance is set to be 0.01Ω, and the sampling rate is 500kHz. The implementation method comprises the following specific steps:
step1: and acquiring fault voltage traveling wave data by using the traveling wave coupling box, and acquiring a fault characteristic enhancement signal.
Step1.1: the fault voltage traveling wave signals of the line are collected by using a traveling wave coupling box;
step1.2: decoupling the fault voltage traveling wave signal by using a line mode transformation matrix to obtain a line mode voltage traveling wave;
step1.3: and carrying out first-order differential transformation on the line mode voltage traveling wave.
Step2: and constructing a circular right shift matrix and a circular left shift matrix by using the voltage traveling wave data.
Step2.1: setting the number m of data points moved each time and the number n of times moved each time;
the number of data points per movement:
wherein f s For sampling frequency, l x V is the wave velocity, which is the distance step of the movement. In the present embodiment, f s 500kHz, l x Take 0.05km and wave speed 300km/ms.
The number of movements:
where l is the line length. In this embodiment, l is 208km, and the number of movements n is 4160.
Step2.2: after the voltage traveling wave sequence moves rightwards by m sampling points, moving the last m sampling points to the head end of the whole sequence to form a first row of a circular right-shift matrix, and circulating the voltage traveling wave sequence until the set moving times n are reached to form a circular right-shift matrix P;
in the matrix P, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular right shift matrix is n rows and k columns. In this embodiment, the number k of sampling points is 693.
Step2.3: after the voltage traveling wave sequence moves leftwards by m sampling points, the m sampling points at the head end are moved to the tail end of the whole sequence to form a first row of a circular left shift matrix, and the voltage traveling wave sequence is circulated until the set movement times n are reached to form a circular left shift matrix Q;
in the matrix Q, each row of elements represents a group of sampling points of the voltage traveling wave sequence, the number of the sampling points is k, and the sampling points are circulated n times altogether, so that the dimension of the circular left shift matrix is n rows and k columns. In this embodiment, the number k of sampling points is 693.
Step3: and calculating the product of the cyclic right shift matrix and the cyclic left shift matrix to obtain a product matrix R. Since the matrices P and Q are homonymous matrices, the multiplication of the homonymous matrices cannot be achieved by conventional matrix multiplication, where the hadamard Ma Chengji of the matrices is used to implement the product operation of the homonymous matrices.
Step4: and summing each row of the product matrix to obtain S (n), wherein the distance corresponding to the row with the smallest sum value is the fault distance. The expression of S (n) is:
if the value of the ith row is the smallest in the S matrix, the distance corresponding to the ith row is the fault distance. In this embodiment, the minimum value is obtained at line 1039 as follows: -5.625×10 45 Due to the movement step l x Taking 0.05km, i.e., 0.05km for each row in the cyclic matrix, the fault distance is 1039×0.05=51.95 km. The ranging result is shown in fig. 3, and the ranging error is: 52-51.95=0.05 km, the range error is small.
A two-way deduced four-terminal flexible direct current transmission line fault location system comprises:
the electric signal acquisition module is used for acquiring and storing fault voltage traveling wave data;
the numerical value calculation module is used for calculating the row sum of the cyclic right shift matrix, the cyclic left shift matrix and the product matrix;
the fault distance measuring module is used for calibrating the distance corresponding to the row with the minimum value and recording the distance measuring result.
The electrical signal acquisition module comprises:
the data acquisition unit is used for acquiring analog signals output by the secondary side of the transformer;
the analog-to-digital conversion unit is used for converting the analog signal into a digital signal;
and the protection starting unit is used for judging whether the digital signal is larger than a set starting threshold value, and if so, reading the starting time and storing the data.
The numerical calculation module includes:
the line-mode conversion unit is used for calculating the line-mode component of the voltage traveling wave of the measuring end;
and the parameter setting unit is used for setting the moving distance step length, the power transmission line length and the sampling frequency. In this embodiment, the moving step length is 0.05km, the transmission line length is 208km, and the sampling frequency is 500kHz.
And the numerical value calculation unit is used for calculating the row sum of the cyclic right shift matrix, the cyclic left shift matrix and the product matrix thereof.
The fault location module includes:
and the amplitude calibration unit is used for calibrating the point with the minimum sum value. Line 1039, with minimum sum value, is-5.625×10 45 。
And the ranging result recording unit is used for recording the ranging result. The ranging result was 51.95km.
The technical scheme is compared:
the results of example 1 and example 2 in this method are compared with the conventional single-ended traveling wave ranging method, respectively, and the comparison results are shown in table 1.
The verification of the table 1 shows that the earth electrode line fault distance measuring method and the system have high distance measuring precision.
While the present invention has been described in detail with reference to the drawings, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.
Claims (7)
1. A fault location method for a four-terminal flexible direct current transmission line based on bidirectional deduction is characterized by comprising the following steps:
step1: acquiring fault voltage traveling wave data by using a traveling wave coupling box, and acquiring a fault characteristic enhancement signal;
step2: constructing a circular right shift matrix and a circular left shift matrix by using fault voltage traveling wave data;
step3: calculating the product of the cyclic right shift matrix and the cyclic left shift matrix to obtain a product matrix;
step4: summing each row of the product matrix, wherein the distance corresponding to the row with the smallest sum value is the fault distance;
the Step2 specifically comprises the following steps:
step2.1: setting the number m of data points moved each time and the number n of times moved each time;
step2.2: after the voltage traveling wave sequence moves rightwards by m sampling points, moving the last m sampling points to the head end of the whole sequence to form a first row of a circular right-shift matrix, and circulating the voltage traveling wave sequence until the set moving times n are reached to form the circular right-shift matrix;
step2.3: after the voltage traveling wave sequence moves leftwards by m sampling points, the m sampling points at the head end are moved to the tail end of the whole sequence to form a first row of a circular left shift matrix, and the voltage traveling wave sequence is circulated until the set movement times n are reached to form the circular left shift matrix.
2. The fault location method for a flexible direct current transmission line with four ends based on bidirectional deduction according to claim 1, wherein Step1 specifically comprises:
step1.1: the fault voltage traveling wave signals of the line are collected by using a traveling wave coupling box;
step1.2: decoupling the fault voltage traveling wave signal by using a line mode transformation matrix to obtain a line mode voltage traveling wave;
step1.3: and carrying out first-order differential transformation on the line mode voltage traveling wave.
3. The fault location method for a flexible direct current transmission line with four terminals based on bidirectional deduction according to claim 1, wherein the number of data points moved each time is:
；
wherein f s For sampling frequency, l x V is the wave velocity, which is the distance step of the movement;
the number of movements:
；
where l is the line length.
4. A system for implementing the two-way deduced four-terminal flexible direct current transmission line fault location method of claim 1 comprising:
the electric signal acquisition module is used for acquiring and storing fault voltage traveling wave data;
the numerical value calculation module is used for calculating the row sum of the cyclic right shift matrix, the cyclic left shift matrix and the product matrix;
the fault distance measuring module is used for calibrating the distance corresponding to the row with the minimum value and recording the distance measuring result.
5. The system of claim 4, wherein the electrical signal acquisition module comprises:
the data acquisition unit is used for acquiring analog signals output by the secondary side of the transformer;
the analog-to-digital conversion unit is used for converting the analog signal into a digital signal;
and the protection starting unit is used for judging whether the digital signal is larger than a set starting threshold value, and if so, reading the starting time and storing the data.
6. The system of claim 4, wherein the numerical calculation module comprises:
the line-mode conversion unit is used for calculating the line-mode component of the voltage traveling wave of the measuring end;
the parameter setting unit is used for setting the moving distance step length, the length of the power transmission line and the sampling frequency;
and the numerical value calculation unit is used for calculating a cyclic right shift matrix, a cyclic left shift matrix and a row sum of the cyclic right shift matrix and the cyclic left shift matrix and the product matrix.
7. The system of claim 4, wherein the fault location module comprises:
the amplitude calibration unit is used for calibrating the point with the minimum sum value;
and the ranging result recording unit is used for recording the ranging result.
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