Frequency domain method for double-end traveling wave fault location of power transmission line
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
A technology of transmission lines and double-ended traveling waves, which is applied to the fault location, detects faults according to the type of conductor, and measures electricity. The effect of improving positioning accuracy
Active Publication Date: 2020-03-27
NORTHEASTERN UNIV
View PDF8 Cites 7 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
[0004] Aiming at the deficiencies of the transmission line fault location method in the prior art, such as difficult determination of the wave velocity and poor positioning effect, the technical problem to be solved by the present invention is to provide a double-ended transmission line that can effectively improve the accuracy of fault location without the need for wave velocity information and data synchronization. Frequency Domain Method for Traveling Wave Fault Location
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more
Image
Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
Click on the blue label to locate the original text in one second.
Reading with bidirectional positioning of images and text.
Smart Image
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0082] Assume that a two-phase ABG ground fault occurs on the line at 120km, the fault grounding resistance is 10Ω, the simulation time is set to 0.12 seconds, and the fault occurrence time is 0.04 seconds. The original data of the fault current measured at both ends of the line are as follows: Figure 4 shown.
[0083] according to figure 2 As shown, the method of the present invention extracts the original fault current data to obtain fault transient current data.
[0084] Through Karenbauer transformation, the fault current is divided into traveling wave line mode and ground mode components.
[0085] The wavelet packet multi-layer decomposition is performed on the linear model and the ground model components at both ends respectively, and the Morlet wavelet basis function is selected in the present invention.
[0086] Using the principle of maximum wavelet coefficient energy to calculate the energy coefficients at each scale, determine the frequency distribution of each ...
Embodiment 2
[0092] Assume that the ABCG three-phase ground fault occurs on the line at 40km, the grounding resistance is 10Ω, the simulation time is set to 0.12 seconds, and the fault occurrence time is 0.04 seconds. The original data of the fault current measured at both ends of the line are as follows: Figure 7 shown.
[0093] according to figure 2 The method shown extracts the original fault current data to obtain fault transient current data.
[0094] Through Karenbauer transformation, the fault current is divided into traveling wave line mode and ground mode components.
[0095] The wavelet packet multi-layer decomposition is performed on the linear model and the ground model components at both ends respectively, and the Morlet wavelet basis function is selected in the present invention.
[0096] Using the principle of maximum wavelet coefficient energy to calculate the energy coefficients at each scale, determine the frequency distribution of each frequency band as follows Fig...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
PUM
Login to view more
Abstract
The invention discloses a frequency domain method for double-end traveling wave fault location of a power transmission line, which comprises the following steps of: 1) when the power transmission linehas a fault, detecting and recording three-phase fault transient current by measuring elements at two ends of the line through a full-cycle method; 2) obtaining a current line mode component and a ground mode component by utilizing Karenbayer transformation; and 3) wavelet packet transformation is performed on the traveling wave line mode and ground mode components, the frequency band where the natural frequency is located is determined through the wavelet coefficient energy maximization principle, the line mode and ground mode natural frequency is calculated, and a distance measurement formula is constructed to calculate the fault distance. According to the method, wave velocity information and data synchronization are not needed, the problem that reflection of a time domain wave head isnot easy to extract is avoided, the error influence caused by uncertain parameters is reduced, a large number of experimental simulations show that the distance measurement precision based on the traveling wave natural frequency can be effectively improved, and therefore the fault positioning precision of the power transmission line is effectively improved.
Description
technical field [0001] The invention relates to the field of electric power system relay protection, in particular to a frequency domain method for distance measurement of double-terminal traveling wave faults of transmission lines. Background technique [0002] With the continuous development of the urban economy, my country's power grid has entered the comprehensive construction stage of the ubiquitous power Internet of Things, large-scale cross-regional power transmission is increasing, and high-voltage long-distance power transmission can effectively ensure the growing power demand in various places. Transmission lines account for the largest proportion of the power grid, and are also the most frequent faults in the power system. Line faults, especially faults that cannot be recovered quickly, will cause large-scale power outages, which will affect the national economy and security. It has a great impact on the stability of the entire power system, so accurate transmissi...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
Application Information
Patent Timeline
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to view more 
Login to view more