CN202177681U - System for positioning fault of DC transmission line - Google Patents

Abstract

A system for positioning fault of a DC transmission line mainly comprises a fault positioning data acquisition device, a GSM/GPRS transmission device, and a GPRS background service program device. The fault positioning data acquisition device mainly comprises a current sensor which can measure the fault current on a lightning conductor through selecting a small section of a conductor on the lightning conductor for electrification and pressure drop; the current sensor on-line monitors a return signal, acquires fault current signal peak values at all fault points when current is detected out, and transmits the peak values to an MCU microprocessor through an optical fiber and an optical fiber receiver; the MCU microprocessor transmits data to the GSM/GPRS transmission device; and the GSM/GPRS transmission device transmits the data back to a center platform through a GSM/GPRS network and by a gateway. The system has the characteristics of low cost, simple fault positioning algorithm, and the like, can carry out analysis calculation to flash over earth-fault current of the DC transmission line and realize fault positioning, and has favorable economic benefits.

Description

The positioning system of direct current transmission line fault

Technical field

The utility model relates to a kind of localization method that is used for direct current transmission line fault, belong to the electrical engineering technical field.

Background technology

Direct current overhead transmission line distance, distribute wide, of living in a varied topographyly, the line walking difficulty is high.Under weather extremes and environmental baseline; Owing to the transmission line of electricity ground short circuit often takes place reasons such as thunderbolt, insulator contamination; Wherein transient fault surpasses 80%, and the minor insulation damage that this type fault causes does not generally have obvious marks, gives to search and has brought very big difficulty.Therefore; How exactly DC power transmission line to be carried out localization of fault; In time compare accurately that localization of fault is the reliable assurance of electric power netting safe running, be significant for the operation maintenance work efficiency that improves DC line to the various ground short circuit faults that take place on the circuit.

The localization of fault of transmission line of electricity can produce remarkable economic efficiency and social benefit, plays crucial effect aspect the loss of outage that accurate fault locator is brought because of transmission line malfunction in the safe operation of guaranteeing whole electrical network and minimizing.Fault Locating Method can be divided into impedance method and traveling wave method two big classes substantially.Traveling wave method is to realize the method for locating through the transmission time of traveling wave fault on faulty line of measuring fault generating; Impedance method is according to the voltage that when fault takes place, measures, the impedance that the magnitude of current calculates fault loop, thereby obtains the method for trouble spot distance, also claims failure analysis methods.Failure analysis methods mainly is divided into single-ended and both-end location sorting technique two big classes.

Also there are a lot of problems technically in the FLU Fault Location Unit of domestic capable ripple, comprising: what 1. Travelling Wave Fault Location detected is row wave-wave head, if row wave-wave head detects failure or the row ripple does not exist when breaking down, then can't carry out localization of fault.2. the precision of Travelling Wave Fault Location is relevant with wave velocity.The time that Travelling Wave Fault Location relies on wave head to arrive the distance measuring equipment mounting points is carried out localization of fault, and bearing accuracy depends on the accuracy of wave velocity.3. the precision of Travelling Wave Fault Location is relevant with sampling rate.The wave velocity of considering transmission line is a little less than the light velocity, and therefore, in order to improve bearing accuracy, the travelling wave ranging device must have higher SF.4. Travelling Wave Fault Location is subject to disturbing effect.Ripple localization of fault just, after any situation that causes row wave-wave head to detect failure takes place, Travelling Wave Fault Location can't be carried out, and all later fault transient data of wave head also can't be used for localization of fault.

Single-ended algorithm is according to single-ended voltage and current that records and necessary systematic parameter, calculates the location algorithm of fault distance.This algorithm detection accuracy is not high, and this is because only use single-ended signal can not eliminate the trouble spot transition resistance fully and to the influence of side system injection current.

Location algorithm based on the two ends data sync is meant that the voltage electric current that is used to locate possesses a reference data, can participate in the location computing directly without conversion.The same with single-ended location algorithm, differential equation method and phasor method are arranged, in theory, the synchronizing voltage magnitude of current of both-end capable of using is eliminated the impedance influences of fault transition resistance and two end systems fully, and algorithm is simple, and bearing accuracy is high, good stability.Along with the communication technology and computer technology rapid development; Dispatching center or two ends, location can obtain the waveform to client information even electric current and voltage by all means; Particularly global position system GPS is open towards civil area in recent years; Let the both-end location must have the support of high-precise synchronization clock that assurance has been arranged, make the precision localization of fault of both-end synchronized sampling be achieved.But owing to work as circuit more in short-term, the parameter error of the model of circuit can be bigger, if use the Fault Locating Method based on the both-end electric parameters, then error equally can be bigger.

Therefore; A kind of direct current transmission line fault localization method that is used for need be provided; Under the complicacy situation of the cost of taking all factors into consideration FLU Fault Location Unit and fault location algorithm, can carry out analytical calculation to the flashover earth-fault current of DC power transmission line and realize localization of fault.

The utility model content

The purpose of the utility model is to restrain the deficiency that secondary prior art exists; And a kind of positioning system of direct current transmission line fault is provided; This system can carry out analytical calculation and realize localization of fault under the complicacy situation of the cost of taking all factors into consideration FLU Fault Location Unit and fault location algorithm to the flashover earth-fault current of DC power transmission line.

In order to solve the problems of the technologies described above, the utility model adopts to come the flashover earth fault of transmission line of electricity is carried out localization of fault based on the shunting situation of transmission line malfunction electric current.The positioning system of described direct current transmission line fault; It mainly comprises: localization of fault data collector, GSM/GPRS transmitting device and GPRS backstage service program device, described localization of fault data collector are mainly by measuring through getting on the lightning conducter on a bit of conductor voltage drop that the current sensor of fault current constitutes on the lightning conducter; Described current sensor on-line monitoring return signal; And when monitoring electric current; Current sensor is gathered the fault current signal maximum of each trouble spot; Be transferred to the MCU microprocessor through optical fiber and fiber optic receiver, the MCU microprocessor is sent to the GSM/GPRS transmitting device with data, and the GSM/GPRS transmitting device sends back central platform through gateway with data through the GSM/GPRS network; Said central platform receives the data of returning; Confirm fault section, read in the fault current maximal value of adjacent two measurement points in trouble spot and the parameter of fault section, carry out localization of fault calculating and become more meticulous differentiation; Precision shows guilty culprit shaft tower section then, and carries out alarm operation.

Described localization of fault data collector is to link to each other with chargeable lithium battery with solar panel through battery management unit with the GSM/GPRS transmitting device.

Described current sensor is a plurality of; And it is a bit of through getting on the lightning conducter respectively; Promptly about 10cm; And require that each current sensor gets on lightning conducter apart from equal and opposite in direction, the fault current on the lightning conducter is measured in voltage drop on the consistent conductor of direction, can implement to monitor fault current direction and the discrete sampling waveform on the transmission line of electricity lightning conducter.

After described GSM/GPRS transmitting device was transferred to GPRS backstage service program device with sampled data, the user can pass through the presence of short message inquiry unit at any time.

It is simple in structure to the utlity model has composition; Easy to use and reliable; Cost is low; Characteristics such as Fault Locating Method is simple, it is under the complicacy situation of the cost of taking all factors into consideration FLU Fault Location Unit and fault location algorithm, can carry out analytical calculation to the flashover earth-fault current of DC power transmission line and realize localization of fault.

Description of drawings

Fig. 1 is used for the overall system pie graph of the direct current transmission line fault localization method of short-term road for the utility model.

Fig. 2 is used for the installation site figure of current sensor of the direct current transmission line fault localization method of short-term road for the utility model.

Fig. 3 is used for the T of the direct current transmission line fault localization method of short-term road for the utility model ₀Fault current when breaking down on the lightning conducter divides flow graph.

Fig. 4 is used for the fault location system algorithm flow chart of the direct current transmission line fault localization method of short-term road for the utility model.

Fig. 5 is used for the precision fault location algorithm process flow diagram of the direct current transmission line fault localization method of short-term road for the utility model.

Fig. 6 is used for the fault shunting computational grid figure of the direct current transmission line fault localization method of short-term road for the utility model.

The equivalent circuit diagram that fault current distributed on lightning conducter and shaft tower when Fig. 7 was used for the fault of direct current transmission line fault localization method of short-term road for the utility model.

Fig. 8 is used for the contiguous shaft tower map of current of the direct current transmission line fault localization method of short-term road for the utility model.

Embodiment

To combine accompanying drawing to set forth the technical scheme of the utility model embodiment in detail below.As shown in Figure 1; The positioning system that present embodiment is used for the short-term road direct current transmission line fault mainly comprises: localization of fault data collector 9, GSM/GPRS transmitting device 8 and GPRS backstage service program device, described localization of fault data collector 9 are mainly by constituting through getting on the lightning conducter current sensor 1 that voltage drop on a bit of conductor measures fault current on the lightning conducter; Described current sensor 1 on-line monitoring return signal; And when monitoring electric current; Current sensor is gathered the fault current signal maximum of each trouble spot; Be transferred to MCU microprocessor 4 through optical fiber 2 and fiber optic receiver 3, MCU microprocessor 4 is sent to GSM/GPRS transmitting device 8 with data, and GSM/GPRS transmitting device 8 sends back central platform 12 through gateway 11 with data through GSM/GPRS network 10; Said central platform 12 receives the data of returning; Confirm fault section, read in the fault current maximal value of adjacent two measurement points in trouble spot and the parameter of fault section, carry out localization of fault calculating and become more meticulous differentiation; Precision shows guilty culprit shaft tower section then, and carries out alarm operation.

Described localization of fault data collector 9 is to link to each other with chargeable lithium battery 6 with solar panel 7 through battery management unit 5 with GSM/GPRS transmitting device 8.

Shown in Figure 2; Described current sensor is a plurality of; And a bit of through getting on the lightning conducter respectively, promptly about 10cm, and require that each current sensor gets on lightning conducter apart from equal and opposite in direction; The fault current on the lightning conducter is measured in voltage drop on the conductor of direction unanimity, can implement fault current direction and discrete sampling waveform on the monitoring transmission line of electricity lightning conducter.

Described GSM/GPRS transmitting device is transferred to GPRS backstage service program device with sampled data, and the while user can pass through the presence of short message inquiry unit at any time.

The utility model can be divided into 5 zones with localization of fault, and the degree of accuracy of localization of fault can be made the section of generation.Come meticulous segmentation through more sensor is installed, can carry out more accurate localization.

As shown in Figure 3, work as T ₀When flashover earth fault takes place in point; The fault current of trouble spot shaft tower toward both sides on aerial earth wire is shunted; The fault current sensor is installed on the shaft tower lightning conducter, through the detection failure sense of current, interval that can localization of faults place; According to the maximal value of current in the fault point, use mesh current analysis that accurate localization is more carried out in the trouble spot again.

Direct current transmission line fault positioning system algorithm such as Fig. 4, shown in 5, the required interval parameter of precision fault location algorithm comprises: shaft tower radix, every basic shaft tower connect span and stake resistance.

The fault current sensor sample frequency that designs in the utility model is 600KHz.At first will to possibly occur in the target line the amplitude and the frequency range of fault current analyze; Because the induction current that fault current causes much smaller than fault current, calculates for simplifying, and disregards the induction current of lead to ground wire; Only consider short-circuit current, it is as shown in Figure 6 to set up network chart.

To the network among Fig. 6, row mesh equation group has:

$\left\{\begin{array}{c}(R_{01}+{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="110602171215.png,110602171221.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1+R_1)I_1-R_1{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="110602171215.png"\; state="\{\{state\}\}">I</figure-callout>}}_2=0\\ -R_1{\mathrm{<figure-callout\; id="1"\; label="I"\; filenames="110602171215.png,110602171221.png"\; state="\{\{state\}\}">I</figure-callout>}}_1+(R_1+{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="110602171215.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2+R_2)I_2-R_2{\mathrm{<figure-callout\; id="3"\; label="I"\; filenames="110602171215.png"\; state="\{\{state\}\}">I</figure-callout>}}_3=0\\ -R_{i-2}{I}_{i-2}+(R_{i-2}+Z_{i-1}+R_{i-1})I_{i-1}-R_{i-1}{I}_i=0\\ -R_{i-1}{I}_{i-1}+(R_{i-1}+Z_i+R_i)I_i-R_i{I}_{i+1}={-I}_0{R}_i\\ -R_i{I}_i+(R_i+Z_{i+1}+R_{i+1})I_{i+1}-R_{i+1}{I}_{i+2}=I_0{R}_i\\ ............................................................\\ -R_{n-2}{I}_{n-2}+(R_{n-2}+Z_{n-1}+R_{n-1})I_{n-1}-R_{n-1}{I}_n=0\\ -R_{n-1}{I}_{n-1}+(R_{n-1}+Z_n+R_{02})I_n=0\end{array}\right.$

By network chart and system of equations, set up the road computation model of this section with analytical calculation software matlab; Be similar to the chain loop that circuit is regarded as the infinite length in two ends, chain of a basic tower does not consider that lightning conducter is the effect of the induction reactance of shaft tower, circuit is reduced to the infinite long resistance chain loop of Fig. 7.

If the A point is a flashover short circuit earth point, the right and left is approximate to be regarded as by the lightning conducter resistance R _xWith pole tower ground resistance R _gThe long-chain shape loop of forming.If the equivalence in loop, both sides inlet R ₀, then by:

R ₀＝R _x+R _g×R ₀/(R _g+R ₀) (2)

: $R_0=1/2(R_x+\sqrt{({R_x}^2+4R_g*R_x)})---\left(3\right)$

Order: R _g/ R _x=k

: $R_0=1/2R_x(1+\sqrt{(1+4k)})---\left(4\right)$

Can the end of Fig. 7 be simplified to the circuit of Fig. 8 during shunting is calculated, the short-circuit current of establishing by phase line input A place is I ₁, can solve I ₃':

${{\mathrm{<figure-callout\; id="3"\; label="I"\; filenames="110602171215.png"\; state="\{\{state\}\}">I</figure-callout>}}_3}^{,}=(1+\sqrt{(1+4k)})*{\mathrm{<figure-callout\; id="1"\; label="I"\; filenames="110602171215.png,110602171221.png"\; state="\{\{state\}\}">I</figure-callout>}}_1/(1+2k+\sqrt{(1+4k)})---\left(5\right)$

So ${{\mathrm{<figure-callout\; id="3"\; label="I"\; filenames="110602171215.png"\; state="\{\{state\}\}">I</figure-callout>}}_3}^{,}/{\mathrm{<figure-callout\; id="3"\; label="I"\; filenames="110602171215.png"\; state="\{\{state\}\}">I</figure-callout>}}_3=2k/(1+2k+\sqrt{(1+4k)})$

This quantitative relationship is under the short circuit two ends are the situation of resistance chain of infinite length, to draw R ₀Calculating and actual value can have slightly difference, particularly short circuit not in the line between or under the short situation of circuit.In addition, if consider that the induction reactance etc. of lightning conducter then is equivalent to the k value and slightly reduces, i.e. I ₃/ I ₁Can be slightly larger, I ₃/ I ₃' can be slightly little, but I ₃/ I ₁And I ₃/ I ₃' variation tendency and shunting ratio roughly do not have very big variation.

Can obtain ground wire fault shunting situation according to top analysis.Try to achieve under the situation of all cyclic currents, adjacent two cyclic currents sizableness, in the opposite direction, then the voltage of this point approaches zero, then can judge the trouble spot on this some position transmission line of electricity.

Claims (3)

1. the positioning system of a direct current transmission line fault; It is characterized in that it mainly comprises: localization of fault data collector (9), GSM/GPRS transmitting device (8) and GPRS backstage service program device, described localization of fault data collector (9) are mainly by constituting through getting on the lightning conducter current sensor (1) that voltage drop on a bit of conductor measures fault current on the lightning conducter; Described current sensor (1) is transferred to MCU microprocessor (4) through optical fiber (2) and fiber optic receiver (3); Said MCU microprocessor (4) links to each other with GSM/GPRS transmitting device (8), and said GSM/GPRS transmitting device (8) links to each other with central platform (12) through gateway (11) through GSM/GPRS network (10).

2. the positioning system of direct current transmission line fault according to claim 1 is characterized in that described localization of fault data collector (9) and GSM/GPRS transmitting device (8) are to link to each other with chargeable lithium battery (6) with solar panel (7) through battery management unit (5).

3. the positioning system of direct current transmission line fault according to claim 1 is characterized in that described current sensor (1) for a plurality of, and a bit of through getting on the lightning conducter respectively, promptly about 10cm.

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