A fault line selection method for double-circuit DC transmission lines on the same tower
A DC transmission line, fault line selection technology, applied in the direction of fault location, electrical digital data processing, special data processing applications, etc., can solve electrical faults such as refusal to move, large amplitude of line mode wave changes, voltage and current, etc. Issues such as unclear features
A DC transmission line, fault line selection technology, applied in the direction of fault location, electrical digital data processing, special data processing applications, etc., can solve electrical faults such as refusal to move, large amplitude of line mode wave changes, voltage and current, etc. Issues such as unclear features
CN104155572BActive Publication Date: 2017-02-22SOUTH CHINA UNIV OF TECH
Image
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment
[0054] Such as figure 1 As shown, a fault line selection method for a double-circuit DC transmission line on the same tower includes the following steps:
[0055] (1) Take the instantaneous value of the voltage at a specific moment before the current moment as the reference quantity, and subtract the reference quantity from the instantaneous value of the voltage at the current moment to obtain the voltage change of the polar line. The four polar lines use 1P, 1N, 2P and 2N represent, 1P and 1N respectively represent the positive pole line and negative pole line of the first loop, 2P and 2N respectively represent the positive pole line and negative pole line of the second loop line, then the voltage changes of the four pole lines are Δu 1P , Δu 1N , Δu 2P , Δu 2N , the voltage variations of the four circuits are respectively Δi 1P , Δi 1N , Δi 2P , Δi 2N , the calculation formula is as follows:
[0056]
[0057]
[0058] Among them, u 1P (t), i 1P (t) represent...
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 fault line selection method for a same-tower double-circuit direct current transmission line. The fault line selection method comprises the following steps: calculating linear modal wave and ground modal wave of the current circuit of the double-circuit according to the polar line voltage and current of the current circuit; calculating ground modal wave change rate; judging whether the ground modal wave change rate is larger than a minimum setting valve or not, if yes, obtaining squared value of the linear modal wave and the ground modal wave respectively, then performing integration, and calculating the integral ratio of the linear modal wave and the ground modal wave, and if not, continuing to judge; distinguishing the fault circuit and the non-fault circuit according to the ratio; distinguishing the fault polar and the non-fault polar in the fault circuit according to the integral value of the ground modal wave. The method has the advantages of high sensitivity, small operation amount, requirement of current circuit information, no communication between different circuits, short determining time, low influence by transition resistance, capability of quickly determining the fault circuit of the same-tower double direct current transmission line without misjudgement and the like.
Description
technical field [0001] The invention relates to a direct current transmission technology of an electric power system, in particular to a fault line selection method of a double-circuit direct current transmission line on the same tower. Background technique [0002] The uneven distribution of natural energy in China and the asymmetric distribution of energy and population make HVDC transmission technology have broad application prospects in China. Compared with high-voltage AC transmission technology, high-voltage direct current transmission technology has the advantages of low unit cost, large transmission power, no need for synchronous operation of AC at both ends, and rapid control and adjustment. Therefore, the use of high-voltage direct current transmission technology is conducive to improving the economic and technical indicators of the power system , operational reliability and scheduling flexibility. [0003] In order to ensure the safe and reliable operation of the...
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
22 Feb 2017
Publication
CN104155572B
- IPC
- G01R31/08; G06F19/00
- Inventors
- 马燕君; 李海锋