CN103592569A - Extra-high voltage direct-current transmission line fault location method based on high frequency value attenuation characteristics - Google Patents
Extra-high voltage direct-current transmission line fault location method based on high frequency value attenuation characteristics Download PDFInfo
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Abstract
The invention relates to an extra-high voltage direct-current transmission line fault location method based on high frequency attenuation characteristics, and belongs to the technical field of extra-high voltage direct-current transmission. According to the extra-high voltage direct-current transmission line fault location method based on the high frequency attenuation characteristics, fault location devices on a rectification side and an inverter side are used for detecting the high frequency values reaching the rectification side and the high frequency values reaching the inverter side when a fault occurs to a certain point of a direct-current transmission line, and the distance between the fault occurring point and the fault location device on the rectification side can be calculated by using the modules of the high frequency values detected on the rectification side and the inverter side. The extra-high voltage direct-current transmission line fault location method based on the high frequency attenuation characteristics can achieve the fault location of the extra-high voltage direct-current transmission line, is a brand new fault location method of the extra-high voltage direct-current transmission line, and has important significance to the safe operation of an extra-high voltage direct-current transmission system.
Description
Technical field
The present invention relates to a kind of extra high voltage direct current transmission line fault distance-finding method based on high frequency content attenuation characteristic, belong to extra-high voltage direct-current transmission technical field.
Background technology
At present, the fault distance-finding method of known DC power transmission line is traveling wave fault location, but traveling wave fault location is subject to the interference of the transition effects such as thunder and lightning, commutation failure, AC fault, and reliability is not high, has the shortcoming of insufficient sensitivity when high resistance ground.And extra-high voltage DC transmission system has power transmission distance, the feature such as with a varied topography, increases the probability of the accidents such as its circuit is short-circuited, thunderbolt, the safe operation of serious threat straight-flow system itself greatly on the way.Be necessary the further novel extra high voltage direct current transmission line fault distance-finding method of research.
Summary of the invention
The invention provides a kind of extra high voltage direct current transmission line fault distance-finding method based on high frequency content attenuation characteristic, for solve existing extra high voltage direct current transmission line traveling wave fault location reliability not high problem, the method reliability is high, can realize extra high voltage direct current transmission line fault localization.
Technical scheme of the present invention is: a kind of extra high voltage direct current transmission line fault distance-finding method based on high frequency content attenuation characteristic, for extra high voltage direct current transmission line, when circuit point breaks down, first in rectification side, by rectification side fault location device 3, detect the fault transient voltage high fdrequency component that arrives rectification side fault location device 3 from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
; Secondly in inversion side, by inversion side fault location device 13, detect from the fault transient voltage high fdrequency component of fault origination point arrival inversion side fault location device 13, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
; Finally utilize the mould of the fault transient voltage signal high fdrequency component that rectification side detects
the mould of the fault transient voltage signal high fdrequency component detecting with inversion side
calculate the distance from fault origination point to rectification side fault location device 3, the location of realizing extra high voltage direct current transmission line fault origination point.
The concrete steps of described distance-finding method are as follows:
A, when extra high voltage direct current transmission line point breaks down, in rectification side, by rectification side fault location device 3, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
;
B, in inversion side, by inversion side fault location device 13, detect the fault transient voltage high fdrequency component that arrives inversion side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
;
C, utilize in A, B
,
calculating fault origination point apart from the distance of rectification side fault location device 3 is:
In formula:
xfor the distance of direct current transmission line fault origination point apart from rectification side fault location device 3,
ldC power transmission line total length,
for DC power transmission line mode attenuation coefficient, by the structures shape of DC power transmission line,
the mould of the high frequency content detecting for rectification side,
the mould of the high frequency content that inversion side detects.From formula (1), fault origination point is apart from the distance of rectification side fault location device 3
xrelevant with following factor: DC power transmission line total length
l, DC power transmission line mode attenuation coefficient
, rectification side fault location device 3 high fdrequency component that detects
, inversion side fault location device 13 high fdrequency component that detects
.DC power transmission line total length wherein
l, DC power transmission line mode attenuation coefficient
fix, so the fault origination point calculating is apart from the distance of rectification side fault location device 3
xthe high fdrequency component only detecting with rectification side fault location device 3
the high fdrequency component detecting with inversion side fault location device 13
relevant, and irrelevant with the high fdrequency component of fault origination point, so this fault distance-finding method has been eliminated fault type and the impact of failure strength on fault distance accuracy, can accurately realize extra high voltage direct current transmission line fault localization.
Principle of work of the present invention is: when certain point of extra high voltage direct current transmission line breaks down, for the fault location device 3 that is arranged on rectification side, after the decay of the transient voltage high fdrequency component that extra high voltage direct current transmission line fault produces by extra high voltage direct current transmission line, arrive distance measuring equipment installation place, for the fault location device 13 that is arranged on inversion side, after the decay of the transient voltage high fdrequency component that extra high voltage direct current transmission line fault produces by extra high voltage direct current transmission line, arrive distance measuring equipment installation place, circuit is longer, decays stronger.The ratio of the high frequency content mould that rectification side and inversion side detect can be eliminated fault type and the impact of failure strength on fault localization accuracy.So, utilize rectification side and inversion side fault location device, detection failure transient voltage signal high fdrequency component also obtains the mould of high fdrequency component, just can calculate fault apart from the distance of rectification side fault location device 3, realizes extra high voltage direct current transmission line fault localization.
The invention has the beneficial effects as follows: utilize the distance measuring equipment of rectification side and inversion side, by extra high voltage direct current transmission line, the attenuation characteristic of high frequency content is calculated to fault apart from the distance of rectification side fault location device, realize extra high voltage direct current transmission line localization of fault.
Accompanying drawing explanation
Accompanying drawing is the extra high voltage direct current transmission line fault localization schematic diagram based on high frequency content attenuation characteristic.
Each label in Fig. 1: 1-rectification top-cross streaming system, 2-rectifier bridge, 3-rectification side fault location device, 4-DC line, 5-inverter bridge, 6-inversion top-cross streaming system, 7-rectification side smoothing reactor, 8-inversion side smoothing reactor, 9-rectification side DC filter, 10-inversion side DC filter, 11-rectification side PLC wave filter, 12-inversion side PLC wave filter, 13-inversion side fault location device ,14-converting plant earthing pole, 15-Inverter Station earthing pole.
Embodiment
Embodiment 1: the extra high voltage direct current transmission line fault localization schematic diagram based on high frequency content attenuation characteristic as shown in Figure 1, for extra high voltage direct current transmission line, when circuit point breaks down, first in rectification side, by rectification side fault location device 3, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
; Secondly in inversion side, by inversion side fault location device 13, detect from the fault transient voltage high fdrequency component of fault origination point arrival inversion side, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
; Finally utilize the mould of the fault transient voltage signal high fdrequency component that rectification side detects
the mould of the fault transient voltage signal high fdrequency component detecting with inversion side
calculate the distance from fault origination point to rectification side fault location device, realize extra high voltage direct current transmission line localization of fault.
The concrete steps of described distance-finding method are as follows:
A, when extra high voltage direct current transmission line point breaks down, in rectification side, by rectification side fault location device 3, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
;
B, in inversion side, by inversion side fault location device 13, detect the fault transient voltage high fdrequency component that arrives inversion side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
;
C, utilize in A, B
,
calculating fault origination point apart from the distance that flows side fault location device 3 is:
In formula:
xfor the distance of direct current transmission line fault origination point apart from rectification side fault location device 3,
ldC power transmission line total length,
for DC power transmission line mode attenuation coefficient,
the mould of the high frequency content detecting for rectification side,
the mould of the high frequency content that inversion side detects.
Embodiment 2: the extra high voltage direct current transmission line fault localization schematic diagram based on high frequency content attenuation characteristic as shown in Figure 1, DC power transmission line total length is
l, when apart from rectification side protection mounting points length being
x's
dwhen direct current transmission line fault occurs point, fault exists
dthe frequency that point produces is
high frequency content be
, in rectification side, by rectification side fault location device 3, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point
, in inversion side, by inversion side fault location device 13, detect the fault transient voltage high fdrequency component that arrives inversion side from fault origination point equally
, then rectification side high fdrequency component is got to the mould that amplitude obtains the high fdrequency component of rectification side fault location device 3
, then inversion side high fdrequency component is got to the mould that amplitude obtains the high fdrequency component of inversion side fault location device 13
, according to the frequency characteristic of transmission line of electricity, have
By formula (2), divided by formula (3), had
（5）
By formula (4), can obtain fault origination point protects the distance of mounting points to be apart from rectification side
Utilize formula (5) just can calculate fault origination point apart from the distance of rectification side fault location device 3, the location of realizing extra high voltage direct current transmission line fault origination point.
By reference to the accompanying drawings the specific embodiment of the present invention is explained in detail above, but the present invention is not limited to above-mentioned embodiment, in the ken possessing those of ordinary skills, can also under the prerequisite that does not depart from aim of the present invention, make various variations.
Claims (2)
1. the extra high voltage direct current transmission line fault distance-finding method based on high frequency content attenuation characteristic, it is characterized in that: for extra high voltage direct current transmission line, when circuit point breaks down, first in rectification side, by rectification side fault location device, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
; Secondly in inversion side, by inversion side fault location device, detect from the fault transient voltage high fdrequency component of fault origination point arrival inversion side, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
; Finally utilize the mould of the fault transient voltage signal high fdrequency component that rectification side detects
the mould of the fault transient voltage signal high fdrequency component detecting with inversion side
calculate the distance from fault origination point to rectification side fault location device, realize extra high voltage direct current transmission line localization of fault.
2. the extra high voltage direct current transmission line fault distance-finding method based on high frequency content attenuation characteristic according to claim 1, is characterized in that: the concrete steps of described distance-finding method are as follows:
A, when extra high voltage direct current transmission line point breaks down, in rectification side, by rectification side fault location device, detect the fault transient voltage high fdrequency component that arrives rectification side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage high fdrequency component that rectification side detects
;
B, in inversion side, by inversion side fault location device, detect the fault transient voltage high fdrequency component that arrives inversion side from fault origination point, then the fault transient voltage signal high fdrequency component detecting is got to the mould that amplitude obtains the fault transient voltage signal high fdrequency component that inversion side detects
;
C, utilize in A, B
,
calculating fault origination point apart from the distance of rectification side fault location device is:
In formula:
xfor the distance of direct current transmission line fault origination point apart from rectification side fault location device,
ldC power transmission line total length,
for DC power transmission line mode attenuation coefficient,
the mould of the high frequency content detecting for rectification side,
the mould of the high frequency content that inversion side detects.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103852692A (en) * | 2014-03-12 | 2014-06-11 | 昆明理工大学 | Ultra-high-voltage direct-current transmission line neural network double end fault location method based on high frequency amount attenuation characteristic |
| CN105116208A (en) * | 2015-08-18 | 2015-12-02 | 昆明理工大学 | Method for diagnosing commutation failure of extra-high-voltage DC power transmission system |
| CN103852692B (en) * | 2014-03-12 | 2016-11-30 | 昆明理工大学 | A kind of extra high voltage direct current transmission line neutral net Two-terminal Fault Location method based on high frequency content attenuation characteristic |
| CN107526002A (en) * | 2017-07-10 | 2017-12-29 | 郑州轻工业学院 | A kind of HVDC circuit fault distance measurements based on concentric relaxation principle |
| CN109212384A (en) * | 2018-10-31 | 2019-01-15 | 海南电网有限责任公司电力科学研究院 | A kind of power transmission line fault locating method based on traveling wave amplitude attenuation theory |
| CN110568320A (en) * | 2018-11-06 | 2019-12-13 | 云南电网有限责任公司电力科学研究院 | Power transmission line lightning fault positioning method based on accurate voltage measurement |
| CN111308263A (en) * | 2019-12-03 | 2020-06-19 | 昆明理工大学 | High-resistance grounding fault detection method for power distribution network |
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| CN103852692A (en) * | 2014-03-12 | 2014-06-11 | 昆明理工大学 | Ultra-high-voltage direct-current transmission line neural network double end fault location method based on high frequency amount attenuation characteristic |
| CN103852692B (en) * | 2014-03-12 | 2016-11-30 | 昆明理工大学 | A kind of extra high voltage direct current transmission line neutral net Two-terminal Fault Location method based on high frequency content attenuation characteristic |
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| CN110568320A (en) * | 2018-11-06 | 2019-12-13 | 云南电网有限责任公司电力科学研究院 | Power transmission line lightning fault positioning method based on accurate voltage measurement |
| CN110568320B (en) * | 2018-11-06 | 2021-10-15 | 云南电网有限责任公司电力科学研究院 | Power transmission line lightning fault positioning method based on accurate voltage measurement |
| CN111308263A (en) * | 2019-12-03 | 2020-06-19 | 昆明理工大学 | High-resistance grounding fault detection method for power distribution network |
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