Grounding grid potential difference filtering method based on starting determination component and wavelet transform
A technology of wavelet transform and determination of components, which is applied to electrical components, impedance networks, digital technology networks, etc., can solve problems such as low proportion of disturbance signals, delay in relay protection processing, and low calculation efficiency, so as to save calculation time, Improve reliability and overcome the effect of poor timeliness
Active Publication Date: 2018-11-23
SOUTHEAST UNIV
View PDF6 Cites 1 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
In the actual working conditions of substations, the proportion of disturbance signals is extremely low. If wavelet transform is directly used to filter all sampled values, the calculation efficiency is not high, which will easily lead to delays in relay protection processing.
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 moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0027] Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail:
[0028] Such as figure 1 As shown, the grounding grid potential difference filtering algorithm based on the starting determination element and wavelet transform of the present invention comprises the following steps:
[0029] Step 1, collecting relay protection current transformer signals in real time;
[0030] The acquisition system includes a current transformer connected in sequence, a pre-analog low-pass filter, a sample-and-hold device, an analog-to-digital converter, a multiplexer, and a single-chip microcomputer.
[0031] Step 2, the starting element judges the signal;
[0032] Because in the steady state process of the power system, a stable power frequency current flows in the power grid, the frequency is 50Hz, and the amplitude is determined by factors such as power supply, load and line parameters, and remains unchanged during the stead...
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 grounding grid potential difference filtering method based on a starting determination component and wavelet transform. The method comprises the steps of judging whether acquired signals of a relay protection current transformer satisfy a steady state condition according to a constraint condition of five consecutive points of the starting component, and further judging the unsatisfied sample data by a determination component based on a waveform coefficient. If the sample data is normal data, the sample data is directly output; if the sample data is abnormal data, thesample data is processed by wavelet transform and then output. The starting determination component is added before the traditional wavelet transform to pre-judge the signals, thereby greatly reducingthe calculation amount, and overcoming the defect of poor timeliness of the traditional filtering algorithm. At the same time, the wavelet transform can effectively filter noise signals caused by thegrounding grid potential difference, ensure the accuracy of relay protection data measurement and avoid the misoperation of a relay protection device.
Description
technical field [0001] The invention relates to a grounding network potential difference filtering method based on a start-up determination element and wavelet transform, and belongs to the technical field of relay protection equipment filtering algorithms. Background technique [0002] UHV substations generally use GIS (Gas insulated substation) switchgear. When the isolating switch is operated, there will be dozens or even hundreds of arcing and arcing at the break of the switch. The disturbance voltage generated by it is continuously refracted and reflected on the bus and short lines, forming a very fast transient overvoltage VFTO (very fast transient over-voltage). VFTO leaks into the ground grid through the protective ground wire on the primary side of the transformer, causing the local potential of the ground grid to rise. Since the secondary cables of UHV substations are generally grounded at both ends, a grounding grid potential difference will be generated at both ...
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
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): H03H17/02
CPCH03H17/0211
Inventor 王立辉黄嘉宇赵凯
Owner SOUTHEAST UNIV