CN111983507A - Arc light grounding fault detection method based on volt-ampere characteristic dynamic trajectory - Google Patents
Arc light grounding fault detection method based on volt-ampere characteristic dynamic trajectory Download PDFInfo
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract
An arc grounding fault detection method based on a volt-ampere characteristic dynamic trajectory comprises the following steps: (1) zero mode current i at feeder outlet of power distribution system0(t) and zero mode voltage u0(t) performing continuous sampling when at a certain time tsThe instantaneous polarity of the zero-mode voltage is opposite to that of the zero-mode current, and a detection program is started; (2) obtaining a discrete value sequence; (3) for both sequences of data; per unit, obtaining 1/4 cycle discrete value sequence containing N points; (4) the initial reverse polarity characteristic of zero-mode voltage and zero-mode current and the clockwise characteristic of the dynamic trajectory of the volt-ampere characteristic in 1/4 cycles are used as the basis for identifying the arc grounding fault, so that the detection of the arc grounding fault is realized; the invention is not influenced by transition resistance and fault initial phase angle, can quickly and reliably identify the occurrence of arc grounding fault of the power distribution system with the neutral point grounded through the arc suppression coil, quickly remove the fault, protect the life safety of personnel, and has wide engineering application prospect.
Description
Technical Field
The invention belongs to the technical field of power system distribution line relay protection, and particularly relates to an arc grounding fault detection method based on a volt-ampere characteristic dynamic trajectory.
Background
The power distribution network utilizes the power distribution equipment to distribute the electric energy from the transmission network and the power plant to various users on site or step by step according to the voltage grade, and the safe and stable operation of the power distribution network is an important guarantee for reliable power supply of the users. The distribution network has a complex structure, the neutral point grounding mode is variable, the fault probability is higher, and the proportion of the single-phase grounding fault is the largest and accounts for about 80% of the total number of the faults.
According to the difference of the neutral point grounding mode, the power distribution network can be divided into: a neutral point active grounding system and a neutral point inactive grounding system. The effective neutral point grounding system mainly based on the grounding of a neutral point through a small resistor belongs to a large-current grounding system, and when a single-phase grounding fault occurs, the amplitude of the fault current is relatively large, and the detection is relatively easy. A neutral point non-effective grounding power distribution network which mainly comprises a neutral point grounding power distribution system through an arc suppression coil belongs to a typical small current grounding system, no obvious power frequency fault current loop exists when a single-phase grounding fault occurs, and the steady-state fault current amplitude is small; due to the compensation effect of the arc suppression coil, the fault power frequency current loses obvious directional characteristics, and the detection difficulty is high. In addition, when a single-phase ground fault occurs, the voltage difference between the line and the ground often causes the breakdown of an air gap or solid dielectric insulation, and the generation of a ground arc.
For a neutral point arc suppression coil grounding power distribution system, with the massive use of the existing fault detection technology based on traveling waves and transient quantities, the positive power rate of fault detection has been improved to a certain extent, and particularly, for a fault of metallic or low transition resistance, the positive power rate has reached over 90%, but unfortunately, in recent years, serious accidents such as personal electric shock casualties, mountain fire induction and the like caused by single-phase grounding faults still frequently occur, and the main reasons are as follows: when the fault occurs, the line is grounded through nonlinear conductive media such as branches, sand, turf and the like, and a nonlinear arc is generated in most cases, and the existing fault detection method exposes obvious defects when dealing with the nonlinear arc grounding fault, such as: the influence of a nonlinear arc is not considered, the weak electrical quantity of the arc grounding fault cannot be effectively dealt with, the sensitivity is poor, and the like, so that the fault exists for a long time and cannot be found in time, the fault is developed into a more serious two-phase short circuit fault or even a three-phase short circuit fault, and even a fire disaster, damage to power equipment, electric shock injury and death of personnel and the like are caused.
At present, most fault detection methods are not focused enough on arc ground fault detection, and there are few methods that can be clearly used for arc ground fault detection. The existing fault detection method is divided into the following steps from the viewpoint of line selection according to different similarities: steady state analysis, transient analysis, traveling wave and artificial intelligence.
Most steady state analysis methods are only suitable for metallic grounding faults, and the detection effect of the method for detecting the arc grounding faults is poor, and the sources of the method are as follows: when arc grounding faults occur to a power distribution system with a neutral point grounded through an arc suppression coil, the content of steady-state electric quantities such as power frequency current, active components and single harmonic components is low, the detection difficulty is high, misjudgment based on the direction, amplitude and the like of the electric quantities is easily caused, and the reliability is poor. Most transient state analysis methods have obvious fault characteristics when the transition resistance is not large and have relatively reliable detection effects, but when the arc grounding fault is responded, the reliability of a detection algorithm is poor due to the nonlinearity of the grounding arc and the high grounding resistance. The traveling wave method has the greatest advantage that the method is not influenced by a neutral point operation mode and can get rid of the interference of an arc suppression coil, but the sensitive starting of the method is easily limited by a transition resistor. In an actual neutral point arc suppression coil grounding power distribution system, the defects that fault sample data of arc grounding fault detection are few, sample selection standards are inconsistent, and physical meanings are unclear, and the artificial intelligence method is fatal are overcome.
The fault detection method developed from the line selection angle in the current stage does not fundamentally solve the detection problem of arc grounding fault detection, because the existing arc grounding fault detection method mostly uses the amplitude out-of-limit of zero-sequence voltage, zero-sequence current or initial traveling wave head as the mark for starting the detection algorithm, it is difficult to set an accurate setting value for the detection algorithm in practice, and reliability and sensitivity cannot be considered at the same time.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide an arc ground fault detection method based on a volt-ampere characteristic dynamic track, which has high reliability and sensitivity by taking a transient reverse polarity characteristic of zero-mode voltage and zero-mode current and a volt-ampere characteristic dynamic track with clockwise characteristic in 1/4 cycle as the basis of arc ground fault detection.
In order to achieve the aim, the technical scheme of the invention is that
An arc grounding fault detection method based on a volt-ampere characteristic dynamic trajectory comprises the following steps:
step (1), zero-mode current i at feeder outlet of distribution system0(t) and zero mode voltage u0(t) performing continuous sampling when at a certain time tsInstantaneous polarity of zero-mode voltage and zero-mode current is opposite, i.e. i0(ts)×u0(ts)<0, starting a detection program, and judging: suspected arc grounding fault occurs, and the step (2) is carried out;
step (2), with a certain sampling rate f, taking 5 kHz-20 kHz as f, extracting 1/4 zero sequence voltage and zero sequence current sequences with cycle length N at the outlet of the circuit, and respectively recording as f0(i)、 f1(i) I 1,2, … … N, and using chebyshev digital filter pair f0(i)、f1(i) Performing band-pass filtering, setting the upper and lower limits of the passband cut-off frequency to be 140Hz and 1000Hz, setting the upper and lower limits of the stopband cut-off frequency to be 100Hz and 1050Hz, obtaining two discrete value sequences of 1/4 cycle waves of electrical quantity, and respectively recording as f0(j)、f1(j)，j＝1,2,……N；
Step (3), for f0(j)、f1(j) The data of the two sequences are per-unit based on the respective maximum value to obtain a discrete value sequence i containing N points of 1/4 cycles0(m)、u0(m)， m＝1,2,……N：
Step (4) mixing0(m)、u0(m) a sequence of coordinate points P ═ P [ P ] combined to form a voltammetric curve1(x1,y1),P2(x2,y2),P3(x3,y3),…PN(xN,yN)]And calculating the distance between all the two continuous vectors by using the formula (2)
And
angle of rotation between theta and theta1, θ2,…θN-1]；
θ＝atan2[(xm-1ym-xmym-1)/(xm-1xm+ym-1ym)] (2)
Step (5), satisfying theta each timeFront side×θRear endCounting for 1 time when the total count is less than or equal to 0, wherein the total count is represented by M, if the total count M is greater than a setting value P, the step (1) is re-entered, and if the total count M is less than or equal to P, the step (6) is entered, and the setting value P is 1/4N;
step (6), calculating the sum sigma theta of all included angles by using a formula (3), if the sigma theta is more than or equal to 0, having a counterclockwise volt-ampere characteristic dynamic track, and re-entering the step (1); if sigma theta is less than 0, the current-voltage characteristic dynamic locus is clockwise, and the judgment is that: an arc grounding fault occurs;
∑θ＝θ1+θ2+…+θn-1 (3)。
the invention has the advantages that: the detection algorithm provided by the invention takes the instantaneous reverse polarity characteristics of zero-mode voltage and zero-mode current as the starting criterion of the arc grounding fault detection algorithm, so that the high sensitivity of the algorithm is ensured; the reliable judgment of the arc grounding fault can be realized by using the volt-ampere characteristic dynamic track with the clockwise characteristic in the 1/4 cycle, the high reliability of the algorithm is ensured, the detection algorithm is not influenced by external interference such as transition resistance, a fault initial phase angle, noise and the like, the fault can be effectively identified in time, the fault hazard is reduced, and the method has important significance for rapidly recovering the stable operation of a power system.
Drawings
Fig. 1 is a flow chart of arc grounding fault detection for a neutral-point arc suppression coil grounded power distribution system according to an embodiment of the present invention.
Figure 2 is a schematic diagram of a 10kV distribution line model employed in the present invention.
Detailed Description
The invention provides an arc grounding fault detection method of a power distribution system with a neutral point grounded through an arc suppression coil based on a volt-ampere characteristic dynamic track, which is described in detail as follows:
the embodiment of the invention adopts a 10kV distribution line model, as shown in figure 2, the system comprises F1-F4Total 4 feeders: 1 branch line, 1 pure cable line, 1 cable hybrid line and 1 pure overhead line; set at 0.165s on the feed line F3An arc grounding fault occurs at a position 10km away from a bus, and the transition resistance at the fault point is regarded as an arc resistance RarcAnd a fixed resistance Rcon(200 ohm) in series, the arc resistance is determined by a nonlinear logarithmic arc model, the compensation degree of an arc suppression coil is set to be 8%, and the sampling frequency f of a simulation model is 10 kHz.
According to the detection algorithm flow chart shown in fig. 1:
step (1), monitoring zero mode voltage and zero mode current at a feeder outlet in real time; at 0.165s, the product of the instantaneous value (-82.18V) of the zero-mode voltage and the instantaneous value (3.88A) of the zero-mode current is less than 0, and the judgment is that: the suspected arc grounding fault occurs, and the detection algorithm is started;
step (2), extracting 1/4 cycle zero-mode current and zero-mode voltage, which are respectively marked as f0(i)、 f1(i)：
Using Chebyshev digital filter pair f0(i)、f1(i) Performing band-pass filtering with band-pass cut-off frequencyThe upper and lower limits of the frequency are set as 140Hz and 1000Hz, the upper and lower limits of the stop band cut-off frequency are set as 100Hz and 1050Hz, two discrete value sequences containing N points of the 1/4 cycle wave of the electrical quantity are obtained and are respectively marked as f0(j)、f1(j)，j＝1,2,……N；
Step (3), for f0(j)、f1(j) The data of the two sequences are per-unit according to respective maximum values; obtaining 1/4 cycles of sequence i containing N discrete values0(m)、u0(m)：
Step (4) mixing0(m)、u0(m) a sequence of coordinate points P ═ P [ P ] combined to form a voltammetric curve1(x1,y1),P2(x2,y2),P3(x3,y3),…Pm(xm,ym)]And calculating the distance between all the two continuous vectors by using the formula (2)
And
angle of rotation between theta and theta1, θ2,…θm-1]：
Step (5), satisfying thetaFront side×θRear endThe total times M which is less than or equal to 0 is less than the setting value P, and 1/4N is recommended to be taken as the setting value P;
step (6), the sum Σ θ of all included angles calculated by the formula (3) is-404.16 ° <0, which indicates a dynamic trajectory of the voltammetry characteristic having a clockwise characteristic, and the determination is performed: the feeder line has an arc ground fault.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (1)
1. An arc grounding fault detection method based on a volt-ampere characteristic dynamic trajectory is characterized by comprising the following steps:
step (1), zero-mode current i at feeder outlet of distribution system0(t) and zero mode voltage u0(t) performing continuous sampling when at a certain time tsInstantaneous polarity of zero-mode voltage and zero-mode current is opposite, i.e. i0(ts)×u0(ts)<0, starting a detection program, and judging: suspected arc grounding fault occurs, and the step (2) is carried out;
step (2), with a certain sampling rate f, taking 5 kHz-20 kHz as f, extracting 1/4 zero sequence voltage and zero sequence current sequences with cycle length N at the outlet of the circuit, and respectively recording as f0(i)、f1(i) I 1,2, … … N, and using chebyshev digital filter pair f0(i)、f1(i) Performing band-pass filtering, setting the upper and lower limits of the passband cut-off frequency to be 140Hz and 1000Hz, setting the upper and lower limits of the stopband cut-off frequency to be 100Hz and 1050Hz, obtaining two discrete value sequences of 1/4 cycle waves of electrical quantity, and respectively recording as f0(j)、f1(j)，j＝1,2,……N；
Step (3), for f0(j)、f1(j) The data of the two sequences are per-unit based on the respective maximum value to obtain a discrete value sequence i containing N points of 1/4 cycles0(m)、u0(m)，m＝1,2,……N：
Step (4) mixing0(m)、u0(m) a sequence of coordinate points P ═ P [ P ] combined to form a voltammetric curve1(x1,y1),P2(x2,y2),P3(x3,y3),…PN(xN,yN)]And calculating the distance between all the two continuous vectors by using the formula (2)
And
angle of rotation between theta and theta1,θ2,…θN-1]：
θ＝atan2[(xm-1ym-xmym-1)/(xm-1xm+ym-1ym)] (2)
Step (5), satisfying theta each timeFront side×θRear endCounting for 1 time when the total count is less than or equal to 0, wherein the total count is represented by M, if the total count M is greater than a setting value P, the step (1) is re-entered, and if the total count M is less than or equal to P, the step (6) is entered, and the setting value P is 1/4N;
step (6), calculating the sum sigma theta of all included angles by using a formula (3), if the sigma theta is more than or equal to 0, having a counterclockwise volt-ampere characteristic dynamic track, and re-entering the step (1); if sigma theta is less than 0, the current-voltage characteristic dynamic locus is clockwise, and the judgment is that: an arc grounding fault occurs;
∑θ＝θ1+θ2+…+θn-1 (3)。
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112986754A (en) * | 2021-05-11 | 2021-06-18 | 国网江西省电力有限公司电力科学研究院 | Small current grounding system fault identification method and device based on data driving |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1800867A (en) * | 2005-12-23 | 2006-07-12 | 山东达驰电气股份有限公司 | Fault line selection method for single-phase-to-ground fault in middle and low voltage distribution network |
| CN102025124A (en) * | 2010-11-30 | 2011-04-20 | 清华大学 | Single phase earth connection relaying protective method |
| CN102780212A (en) * | 2012-07-20 | 2012-11-14 | 清华大学 | Single-phase grounding traveling-wave protection device for distribution line |
| CN103558511A (en) * | 2013-11-18 | 2014-02-05 | 国家电网公司 | Online earth fault positioning system for power distribution network |
| CN203688722U (en) * | 2014-01-24 | 2014-07-02 | 泉州维盾电气有限公司 | Single-phase grounding fault processing device for small-current grounding system |
| CN107505539A (en) * | 2017-10-23 | 2017-12-22 | 云南电网有限责任公司电力科学研究院 | A kind of distribution arc grounding fault identification method |
| CN109188200A (en) * | 2018-08-31 | 2019-01-11 | 华中科技大学 | A kind of power distribution network transient fault selection method for ground fault transfer control |
-
2020
- 2020-06-08 CN CN202010511750.0A patent/CN111983507B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1800867A (en) * | 2005-12-23 | 2006-07-12 | 山东达驰电气股份有限公司 | Fault line selection method for single-phase-to-ground fault in middle and low voltage distribution network |
| CN102025124A (en) * | 2010-11-30 | 2011-04-20 | 清华大学 | Single phase earth connection relaying protective method |
| CN102780212A (en) * | 2012-07-20 | 2012-11-14 | 清华大学 | Single-phase grounding traveling-wave protection device for distribution line |
| CN103558511A (en) * | 2013-11-18 | 2014-02-05 | 国家电网公司 | Online earth fault positioning system for power distribution network |
| CN203688722U (en) * | 2014-01-24 | 2014-07-02 | 泉州维盾电气有限公司 | Single-phase grounding fault processing device for small-current grounding system |
| CN107505539A (en) * | 2017-10-23 | 2017-12-22 | 云南电网有限责任公司电力科学研究院 | A kind of distribution arc grounding fault identification method |
| CN109188200A (en) * | 2018-08-31 | 2019-01-11 | 华中科技大学 | A kind of power distribution network transient fault selection method for ground fault transfer control |
Non-Patent Citations (4)
| Title |
|---|
| 张勇志等: "小电阻接地***高阻弧光接地故障特征分析", 《机电工程技术》 * |
| 王宾: "配网高阻接地故障伏安特性分析及检测", 《中国电机工程学报》 * |
| 董海波等: "基于电流融合的单相接地故障选线方法研究", 《电气应用》 * |
| 韩瑞等: "零序电压轨迹在船舶中压电力***中的分析及应用", 《电气应用》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112986754A (en) * | 2021-05-11 | 2021-06-18 | 国网江西省电力有限公司电力科学研究院 | Small current grounding system fault identification method and device based on data driving |
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