CN103474980B - A kind of power distribution network single-phase ground protection method based on transient power direction - Google Patents
A kind of power distribution network single-phase ground protection method based on transient power direction Download PDFInfo
- Publication number
- CN103474980B CN103474980B CN201310391733.8A CN201310391733A CN103474980B CN 103474980 B CN103474980 B CN 103474980B CN 201310391733 A CN201310391733 A CN 201310391733A CN 103474980 B CN103474980 B CN 103474980B
- Authority
- CN
- China
- Prior art keywords
- zero
- feeder line
- fault
- transient
- sequence
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The present invention relates to a kind of power distribution network single-phase ground protection method based on transient power direction, belong to Relay Protection Technology in Power System field.The present invention is for the power distribution network of neutral by arc extinction coil grounding, when the feeder line generation single phase ground fault of wherein, first calculate after a failure the product integral of bus residual voltage and each feeder line zero-sequence current in short time-window, obtain the transient zero-sequence performance number of each bar feeder line; Then the transient zero-sequence performance number of each bar feeder line and null value are compared, when the transient zero-sequence performance number of certain feeder line is less than zero, judge this circuit generation forward fault, protection component action; When the transient zero-sequence performance number of certain feeder line is greater than zero, judge this circuit generation reverse fault, protection component is failure to actuate.Cost of the present invention is low, reduces the difficulty that method uses, adds the reliability of protection.
Description
Technical field
The present invention relates to a kind of power distribution network single-phase ground protection method based on transient power direction, belong to Relay Protection Technology in Power System field.
Background technology
China's town and country power distribution network all belongs to small current neutral grounding system, i.e. isolated neutral or neutral by arc extinction coil grounding system.Small current neutral grounding system breaks down and can affect healthy phases voltage to earth and cause it and raise, and voltage raises to produce the insulation of grid equipment and destroys; Particularly intermittent arcing ground, arc overvoltage can be caused, this voltage is by destroying system insulation and then developing into alternate or multipoint earthing short circuit, cause system overvoltage, thus damage equipment, destroy system safety operation, therefore must find faulty line accurately, fast and make faulty line and isolation of system in time.
The most original partition method is by manually cutting off faulty line after route selection success.In recent years, some one-phase ground protection devices obtain application in practice, serve positive effect to the safe operation of electrical network.But the practical manifestation of partial devices is also unsatisfactory, and the phenomenon of malfunction, tripping happens occasionally.Existing one-phase ground protection device based on principle be generally: zero-sequence current is than width method, zero-sequence current relative phase method and harmonic component method etc.Zero-sequence current make use of than width method the feature that faulty line zero-sequence current equals non-fault line capacitive earth current sum; the selection of the introducing of cable line, the impact of transition resistance and operational mode all likely causes the capacitive earth current of certain circuit to be greater than the situation of other all line mutual-ground capacitor electric current sums, and this will cause protective device generation malfunction.Zero-sequence current relative phase method make use of the faulty line zero-sequence current feature contrary with non-fault line zero-sequence current flow direction, and when circuit shorter zero-sequence current value is less, the judgement in direction is comparatively difficult, loses efficacy after resonant earthed system compensation process occurs.Harmonic component method still make use of colony amplitude comparison phase comparing method in essence, fundamentally can not solve above-mentioned two kinds of method Problems existing and deficiency, the phenomenon of malfunction, tripping or often appearance.
Summary of the invention
The invention provides a kind of power distribution network single-phase ground protection method based on transient power direction; for the existing one-phase ground protection principle of solution because zero-sequence current is little, direction of current flow is difficult to differentiate; the impact of compensation process and non-fault line zero-sequence current are greater than All other routes zero-sequence current sum and cause the deficiency of protective device malfunction or tripping, to improve the reliability of protective device.
Technical scheme of the present invention is: a kind of power distribution network single-phase ground protection method based on transient power direction, for the power distribution network of neutral by arc extinction coil grounding, when the feeder line generation single phase ground fault of wherein, first calculate after a failure the product integral of bus residual voltage and each feeder line zero-sequence current in short time-window, obtain the transient zero-sequence performance number of each bar feeder line; Then the transient zero-sequence performance number of each bar feeder line and null value are compared, when the transient zero-sequence performance number of certain feeder line is less than zero, judge this circuit generation forward fault, protection component action; When the transient zero-sequence performance number of certain feeder line is greater than zero, judge this circuit generation reverse fault, protection component is failure to actuate.
Described single-phase ground protection method concrete steps are as follows:
A, when the feeder line generation single phase ground fault of wherein, in short time-window, calculate the product integral of bus residual voltage and each feeder line zero-sequence current first after a failure
s(
j), obtain the transient zero-sequence performance number of each bar feeder line:
（1）
In formula:
t 0for the moment occurs fault,
for intercepting the time window length of bus residual voltage and feeder line zero-sequence current after fault,
u 0(
t) bus residual voltage,
i 0
j (
t) be the zero-sequence current of each feeder line,
nfor the number of feeder line;
B, the transient zero-sequence performance number of each bar feeder line and null value to be compared, and determine fault direction:
When
s(
j) < 0 time, be defined as positive direction fault; When
s(
j) > 0 time, be defined as reverse direction failure;
C, according to the operating criterion of fault direction determination protection component be:
When being defined as positive direction fault, protection component action; When being defined as reverse direction failure, protection component is failure to actuate.
Operation principle of the present invention is: as shown in Figure 1, for distribution network feeder break down after zero-sequence fault component equivalent circuit diagram, in figure
kfor switch, L is arc suppression coil,
rfor earth resistance.
ktime closed, distribution is neutral by arc extinction coil grounding system (resonant earthed system),
kduring unlatching, distribution is isolated neutral system.
r 1,
r 2,
r 3...
r n for protection component,
u 0for the residual voltage of bus,
i 01,
i 02,
i 03,
i 0
n for the zero-sequence current of each feeder line, the direction of arrow of its correspondence is the positive direction that protection component is installed, and the installation direction of the protection component on all feeder lines is consistent.For resonant earthed system, occur in the short time-window after single phase ground fault, fault transient zero-sequence current is not by the impact of arc suppression coil, and system can regard isolated neutral system as.After single phase ground fault occurs, fault point can be regarded as and adds an equivalent source--
u f , now the zero-sequence current of fault feeder equals each bar and perfects feeder line zero-sequence current sum, and the zero-sequence current direction of fault feeder is feeder line flows to bus, and the zero-sequence current direction perfecting feeder line is that bus flows to feeder line.If the integration of the zero-sequence current product of definition bus place residual voltage and each bar feeder line
for each bar feeder line transient zero-sequence power, in formula
t 0for the moment occurs fault,
for intercepting the time window length of bus residual voltage and feeder line zero-sequence current after fault,
u 0(
t) bus residual voltage,
i 0
j (
t) be the zero-sequence current of each feeder line,
nfor the number of feeder line, then the direction of each feeder line transient zero-sequence power is identical with the direction of each feeder line zero-sequence current (because the zero-sequence current direction of fault feeder is that feeder line flows to bus, the zero-sequence current direction perfecting feeder line is that bus flows to feeder line, so the direction of fault feeder transient zero-sequence power is feeder line flow to bus, the direction perfecting feeder line transient zero-sequence power is that bus flows to feeder line).Therefore for protection component, definable is worked as
s(
j) < 0 time be positive direction fault, when
s(
j) > 0 time be reverse direction failure, therefore can build protection component operating criterion and be: during positive direction fault, the direction of transient zero-sequence power is contrary with the positive direction that protection component is installed, protection component starts and disconnects; During reverse direction failure, the direction of transient zero-sequence power is identical with the positive direction that protection component is installed, and protection component is failure to actuate.
The invention has the beneficial effects as follows:
1, this method is using the operating criterion of the symbol of the product (transient zero-sequence power) of bus residual voltage and feeder line zero-sequence current as protection component, when zero-sequence current is less, than the operating criterion of symbol as protection component utilizing merely feeder line zero-sequence current, reliability is higher;
2, intercept bus residual voltage and feeder line zero-sequence current calculating transient zero-sequence power in the short time-window of this method after fault occurs, now arc suppression coil is not also to compensating system, therefore this method avoid the impact of arc suppression coil compensation effect;
3, whether the action of this method protection component only depends on the judgement of this feeder line transient zero-sequence power direction; do not rely on the relevant information of other feeder lines; avoid employing colony amplitude comparison phase comparing method; non-fault line zero-sequence current is greater than to the special circumstances of All other routes zero-sequence current sum, the reliability of protection is higher.
Accompanying drawing explanation
Fig. 1 is zero-sequence fault component equivalent circuit diagram after distribution network feeder of the present invention breaks down;
Fig. 2 is the distribution simulation model of the neutral by arc extinction coil grounding of the embodiment of the present invention 1 and embodiment 2;
The residual voltage oscillogram of bus in window when Fig. 3 is 5ms after the embodiment of the present invention 1 fault;
Feeder line in window when Fig. 4 is 5ms after the embodiment of the present invention 1 fault
l 1zero-sequence current oscillogram;
Feeder line in window when Fig. 5 is 5ms after the embodiment of the present invention 1 fault
l 2zero-sequence current oscillogram;
Feeder line in window when Fig. 6 is 5ms after the embodiment of the present invention 1 fault
l 3zero-sequence current oscillogram;
Feeder line in window when Fig. 7 is 5ms after the embodiment of the present invention 1 fault
l 4zero-sequence current oscillogram;
Feeder line in window when Fig. 8 is 5ms after the embodiment of the present invention 1 fault
l 5zero-sequence current oscillogram;
Feeder line in window when Fig. 9 is 5ms after the embodiment of the present invention 1 fault
l 6zero-sequence current oscillogram;
The residual voltage oscillogram of bus in window when Figure 10 is 5ms after the embodiment of the present invention 2 fault;
Feeder line in window when Figure 11 is 5ms after the embodiment of the present invention 2 fault
l 1zero-sequence current oscillogram;
Feeder line in window when Figure 12 is 5ms after the embodiment of the present invention 2 fault
l 2zero-sequence current oscillogram;
Feeder line in window when Figure 13 is 5ms after the embodiment of the present invention 2 fault
l 3zero-sequence current oscillogram;
Feeder line in window when Figure 14 is 5ms after the embodiment of the present invention 2 fault
l 4zero-sequence current oscillogram;
Feeder line in window when Figure 15 is 5ms after the embodiment of the present invention 2 fault
l 5zero-sequence current oscillogram;
Feeder line in window when Figure 16 is 5ms after the embodiment of the present invention 2 fault
l 6zero-sequence current oscillogram.
Embodiment
Embodiment 1: be illustrated in figure 2 the distribution that 6 feed out the 35kV neutral by arc extinction coil grounding of circuit composition, the G in this electrical network is infinitely great power supply; T is main transformer, and no-load voltage ratio is 110kV/35kV, and connection set is YN/d11; China's power distribution network main transformer distribution voltage side is generally delta connection, and system does not exist neutral point, need obtain for the neutral point of grounding through arc, can set up the way that grounding transformer is exactly the best, T herein when system adopts during resonance neutral grounding
zfor the special zigzag transformer of compensation network ground connection; L is arc suppression coil, and R is the damping resistance of arc suppression coil.Circuit adopts overhead transmission line, overhead line-cable hybrid line and cable line three kinds of circuits, and the numbering of six feeder lines is followed successively by
l 1,
l 2,
l 3...
l 6, wherein,
l 1for overhead wire, length is 15km;
l 2for cable, length is 6km;
l 3for overhead wire, length is 18km;
l 4for cable joint line, cable length is 5km, and overhead wire length is 12km;
l 5for overhead wire, length is 30km;
l 6for cable, length is 8km.Load selects firm power load model, wherein
p=800
kW,
q=140
kVar;
r 1,
r 2,
r 3...
r 6for protection component, the direction of its upward arrow is the positive direction that protection component is installed.
Now suppose feeder line
l 1there is single phase ground fault, earth resistance 20 Ω in distance bus 5km place A phase, fault angle is 90 °, and sample frequency is 10kHz.After fault, during 5ms, in window, the oscillogram of bus residual voltage is as shown in Figure 3; Feeder line
l 1,
l 2,
l 3...
l 6zero-sequence current oscillogram as shown in figures 4-9.Bus residual voltage after intercepting fault during 1ms in window and each feeder line zero-sequence current value, the transient zero-sequence performance number calculating each bar feeder line according to formula (1) is:
S(
j)=[-7.48×10
61.86×10
61.93×10
51.96×10
64.13×10
53.08×10
6]
Wherein,
s(1)=-7.48 × 10
6<0, protection component
r 1be detected as positive direction fault, protection component
r 1start and disconnect.
And,
s(2),
s(3),
s(4),
s(5) and
s(6) all zero is greater than, protection component
r 2,
r 3...
r 6be detected as negative direction fault, protection component
r 2,
r 3...
r 6be failure to actuate.Protection act is consistent with hypothesis demand, and protection act is correct.
Embodiment 2: the distribution network systems of neutral by arc extinction coil grounding as shown in Figure 2, system parameters is identical with embodiment 1.Now suppose feeder line
l 2there is single phase ground fault, 90 °, the initial phase angle of fault in distance bus 4km place A phase, fault resistance is 20 Ω, and sample frequency is 10kHz.After fault, during 5ms, in window, the oscillogram of bus residual voltage is as shown in Figure 10; Feeder line
l 1,
l 2,
l 3...
l 6zero-sequence current oscillogram as illustrated in figures 11-16.Bus residual voltage after intercepting fault during 1ms in window and each feeder line zero-sequence current value, the transient zero-sequence performance number calculating each bar feeder line according to formula formula (1) is:
S(
j)=[2.00×10
5-1.40×10
81.27×10
62.22×10
51.03×10
71.05×10
8]
Wherein,
s(2)=-1.40 × 10
8<0, protection component
r 2be detected as positive direction fault, protection component
r 2start and disconnect.
And,
s(1),
s(3),
s(4),
s(5) and
s(6) all zero is greater than, protection component
r 1,
r 3...
r 6be detected as negative direction fault, protection component
r 1,
r 3...
r 6be failure to actuate.Protection act is consistent with hypothesis demand, and protection act is correct.
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 execution mode, in the ken that those of ordinary skill in the art possess, various change can also be made under the prerequisite not departing from present inventive concept.
Claims (1)
1. the power distribution network single-phase ground protection method based on transient power direction, it is characterized in that: for the power distribution network of neutral by arc extinction coil grounding, when the feeder line generation single phase ground fault of wherein, first calculate after a failure the product integral of bus residual voltage and each feeder line zero-sequence current in short time-window, obtain the transient zero-sequence performance number of each bar feeder line; Then the transient zero-sequence performance number of each bar feeder line and null value are compared, when the transient zero-sequence performance number of certain feeder line is less than zero, judge circuit generation forward fault, protection component action; When the transient zero-sequence performance number of certain feeder line is greater than zero, judge circuit generation reverse fault, protection component is failure to actuate;
Described single-phase ground protection method concrete steps are as follows:
A, when the feeder line generation single phase ground fault of wherein, calculate the product integral S (j) of bus residual voltage and each feeder line zero-sequence current first after a failure in short time-window, obtain the transient zero-sequence performance number of each bar feeder line:
In formula: t
0for the moment occurs fault, τ is the time window length intercepting bus residual voltage and feeder line zero-sequence current after fault, u
0(t) bus residual voltage, i
0jt () is the zero-sequence current of each feeder line, N is the number of feeder line;
B, the transient zero-sequence performance number of each bar feeder line and null value to be compared, and determine fault direction:
As S (j) < 0, be defined as positive direction fault; As S (j) > 0, be defined as reverse direction failure;
C, according to the operating criterion of fault direction determination protection component be:
When being defined as positive direction fault, protection component action; When being defined as reverse direction failure, protection component is failure to actuate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310391733.8A CN103474980B (en) | 2013-09-02 | 2013-09-02 | A kind of power distribution network single-phase ground protection method based on transient power direction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310391733.8A CN103474980B (en) | 2013-09-02 | 2013-09-02 | A kind of power distribution network single-phase ground protection method based on transient power direction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103474980A CN103474980A (en) | 2013-12-25 |
| CN103474980B true CN103474980B (en) | 2016-04-20 |
Family
ID=49799724
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310391733.8A Active CN103474980B (en) | 2013-09-02 | 2013-09-02 | A kind of power distribution network single-phase ground protection method based on transient power direction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103474980B (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103954876B (en) * | 2014-03-21 | 2017-01-04 | 珠海许继电气有限公司 | A kind of distribution single-phase earth fault detecting method based on transient state component |
| CN104111403A (en) * | 2014-04-24 | 2014-10-22 | 杨庆申 | Microcomputer integrated protection line-selection method for low-current earthed power system |
| CN104950217B (en) * | 2015-06-17 | 2017-12-19 | 北京四方继保自动化股份有限公司 | A kind of small current earthing wire-selecting method based on temporal variations amount power direction principle |
| CN104967104A (en) * | 2015-06-30 | 2015-10-07 | 昆明理工大学 | Transient energy protection method of transmission line with unified power flow controller |
| EP3571516B1 (en) | 2017-01-22 | 2021-12-08 | Hitachi Energy Switzerland AG | Method and control system for fault direction detection |
| CN109997287B (en) * | 2017-06-15 | 2021-10-29 | Abb电网瑞士股份公司 | Method and control system for fault direction detection |
| CN111505438B (en) * | 2020-04-17 | 2022-03-29 | 南京南瑞继保电气有限公司 | Improved self-adaptive feeder automation method |
| CN111830365A (en) * | 2020-06-20 | 2020-10-27 | 青岛鼎信通讯股份有限公司 | Multi-transient statistical fault positioning method applied to power grid fault diagnosis |
| CN111900695B (en) * | 2020-07-07 | 2022-07-08 | 长沙理工大学 | Single-phase earth fault removing method and device |
| CN112630686A (en) * | 2020-12-31 | 2021-04-09 | 南京铁道职业技术学院 | Method and system for identifying single-phase earth fault line of urban rail medium-voltage system |
| CN112731201B (en) * | 2021-03-22 | 2022-08-12 | 上海宏力达信息技术股份有限公司 | Single-phase earth fault studying and judging method and system in transient zero sequence power direction |
| CN113013880A (en) * | 2021-04-20 | 2021-06-22 | 西安兴汇电力科技有限公司 | Fault processing method based on 5G communication module distribution line |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1667424A (en) * | 2005-02-26 | 2005-09-14 | 重庆大学 | Earth fault line-selecting method for arc suppression coil earthing system |
| EP2417467B1 (en) * | 2009-04-10 | 2013-03-20 | ALSTOM Technology Ltd | Method and system for transient and intermittent earth fault detection and direction determination in a three-phase medium voltage electric power distribution system |
| CN103245879A (en) * | 2013-04-18 | 2013-08-14 | 国家电网公司 | Small current neutral grounding fault location method based on direction of transient state reactive power |
-
2013
- 2013-09-02 CN CN201310391733.8A patent/CN103474980B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1667424A (en) * | 2005-02-26 | 2005-09-14 | 重庆大学 | Earth fault line-selecting method for arc suppression coil earthing system |
| EP2417467B1 (en) * | 2009-04-10 | 2013-03-20 | ALSTOM Technology Ltd | Method and system for transient and intermittent earth fault detection and direction determination in a three-phase medium voltage electric power distribution system |
| CN103245879A (en) * | 2013-04-18 | 2013-08-14 | 国家电网公司 | Small current neutral grounding fault location method based on direction of transient state reactive power |
Non-Patent Citations (2)
| Title |
|---|
| 消弧线圈接地系统暂态能量选线新方法;周念成等;《重庆大学学报》;20091231;第32卷(第12期);第1425-1430页 * |
| 谐振接地电网故障暂态能量a适应选线新方法;束洪春等;《电力系统自动化》;20060610;第30卷(第11期);第72-76页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103474980A (en) | 2013-12-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103474980B (en) | A kind of power distribution network single-phase ground protection method based on transient power direction | |
| CN103474981B (en) | A kind of distribution network single-phase ground protection method based on the multistage differential transformation direction of zero-sequence current | |
| CN103474974B (en) | A kind of distribution network single-phase ground protection method based on zero-sequence current Sudden Changing Rate fitting a straight line direction | |
| EP3267460B1 (en) | Direct-current interruption device | |
| CN103424669B (en) | A kind of selection method utilizing fault feeder zero-sequence current matrix principal component analysis (PCA) first principal component | |
| Descloux et al. | Protection algorithm based on differential voltage measurement for MTDC grids | |
| CN103424668B (en) | A kind of continuous selection method of arc grounding fault utilizing the principal component analysis (PCA) of feeder line zero-sequence current and evidence theory fusion | |
| CN108594071B (en) | Single-phase earth fault detection method for neutral point small-resistance earth distribution network | |
| CN102520314A (en) | Detection system and detection method for single-phase grounding fault line selection in small current grounding system | |
| CN107064733A (en) | Power distribution network flexible ground device single-phase earth fault line selection and arc extinguishing method | |
| CN102944806B (en) | Zero sequence current polarity comparison-based resonant earthed system line selection method | |
| CN103207352B (en) | Route selection impedance magnitude characteristic is utilized to realize wire selection method for power distribution network single phase earthing failure | |
| CN110190591B (en) | Automatic processing method and system for single-phase earth fault | |
| CN103163430A (en) | Resonant grounding system fault line selection method by combining complex wavelets with ANN (artificial neural network) | |
| CN104316819B (en) | Small current grounding line selection method based on zero-sequence currents | |
| CN202362416U (en) | Detection system of one-phase ground fault line selection in small current neutral grounding system | |
| CN103207354A (en) | Maximum line selection coefficient principle based single-phase earth fault line selection method for power distribution network | |
| CN103116115A (en) | Network-distribution single-phase failure line selection method based on virtual active power increment maximal principle | |
| CN106908697A (en) | A kind of synthetic power-frequency and the distribution network fault line selection method in transient reactive power direction | |
| CN103293448B (en) | Identification method of single-phase ground fault and virtual grounding based on semi-cycle energy ratio | |
| CN202586308U (en) | Comprehensive grounding protective device for microcomputer | |
| CN105866608A (en) | Power distribution network fault line selection method based on unique through-flow characteristic of resistive current | |
| CN113659547B (en) | Power distribution network differential protection data synchronization method and system based on effective zero crossing point | |
| CN107516877B (en) | Small resistance grounding system failure protecting device, system and method | |
| CN104133158A (en) | Distribution network fault line selection method based on zero-mode current multi-order difference transformation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |