CN206960596U - A kind of transient state recording indicator - Google Patents

Abstract

It the utility model is related to supply line's fault detection technique field, it is related to a kind of transient state recording indicator, in particular include MSP430FR697xPM/RGC, current electric fields collecting unit and external electricity and interior power supply unit, the current electric fields collecting unit includes electronic current collector, and rectifier bridge connects overhead transmission line by high magnetic conduction CT power takings sensor.The utility model, the online power taking ability of current electric fields collecting unit is strong, and power taking electric current 5A can normal work；External electricity and interior power supply unit, realize ± 1% high-acruracy survey electric current；Precision reaches ± 50 μ s during three-phase synchronous pair；Realize small current neutral grounding system earth fault, particularly instantaneity earth fault, complicated intermittent grounding fault, high resistance earthing fault are accurately positioned；Complex fault process carries out backtracking inverting by recording waveform, and strong foundation is provided for accident analysis；Circuit abnormality sends early warning in advance.

Description

A kind of transient state recording indicator

Technical field

Supply line's fault detection technique field is the utility model is related to, specially a kind of transient state recording indicator.

Background technology

Two kinds of principal modes of distribution network line are：It is laid on the cable run of underground and the overhead line using tower erection Road.For the distribution network line of big city particularly main city zone, substantially based on buried cable, generally use connects through small resistor Ground mode, so when singlephase earth fault occurs, larger lasting power frequency (50Hz) faulted phase current and power frequency can be produced Zero-sequence current, Earth Fault Detection positioning are easier.For the non-main city zone in big city, small and medium-sized cities, the combination area of city and country and wide Large village, the distribution network line in pastoral area, still based on overhead line power distribution network, generally use is earth-free and through grounding through arc Mode, when singlephase earth fault occurs, caused lasting power frequency faulted phase current and power frequency zero-sequence current amplitude are smaller, this It is the origin of small current neutral grounding mode title.

Singlephase earth fault be small current neutral grounding power distribution network it is faulty it is middle most frequent one kind occurs, it is faulty to account for institute 50%~80%.After long-time singlephase earth fault occurs, it is necessary to find Single-phase Ground Connection Failure as early as possible, fix a breakdown. Otherwise overvoltage caused by earth fault, the power systems such as electric cable explosion, voltage transformer pt burn, bus burns can be caused Accident.If ground path can be brought greatly hidden as regular link longtime running to local resident, safety of livestock simultaneously Suffer from.

Such as the overhead transmission line fault location monitoring system and method that Chinese Patent Application No. is 201510311336.4, system Including fault detector, concentrator substation and main website, fault detector includes MCU, current transformer, capacitive divider, signal Detect circuit, ESAM safety chips and the wireless child node of micropower；Concentrator substation includes communication terminal, micropower wireless center Node, GPRS remote communication modules；Main website includes generalized information system, mis system and monitoring client.Method comprises the following steps：Collection is simultaneously Calculate electric current and voltage signal；Judge that short trouble adds first half-wave to judge earth fault by the seventh harmonic；With marking failure Put and notify patrol officer.Reach accuracy of judgement, and strong antijamming capability, it is safe, effectively it can tie up auxiliary power grid Nurse makees, and lifts grid automation level.But have the following disadvantages：The linearity, bandwidth, transient state of the current transformer in measurement Performance is not high in response, and ferrimagnet can saturation particularly in high current；It is weak to pick up distribution network line current signal ability； It is low to measure current precision.

Utility model content

The purpose of this utility model is to provide a kind of transient state recording indicator, to solve what is proposed in above-mentioned background technology Problem.

To achieve the above object, the utility model provides following technical scheme：

A kind of transient state recording indicator, including MSP430FR697xPM/RGC, current electric fields collecting unit and outside take Electric and interior power supply unit, the current electric fields collecting unit include electronic current collector, one end of the electronic current collector Amplifier LMV611U (3,4) pin is connected, short circuit resistance R between amplifier LMV611U (Isosorbide-5-Nitrae) pin, and 1 pin and connect two Identical amplifier LMV61U1；Short circuit is by RC circuits in parallel electric capacity R and electric capacity C between amplifier LMV61U1 (Isosorbide-5-Nitrae) pin, and it 1 Pin is connected to MSP430FR697xPM/RGC by I1, I2 respectively；

External electricity and interior power supply unit include voltage-regulator diode Z3 and transient supression diode Z4 in parallel, and it is simultaneously coupled Point meets MSP430FR697xPM/RGC, while is also connected to the 3 of amplifier TLV3401U2 by resistance R1, diode D1, resistance R2 Pin, amplifier TLV3401U2 3 pins are also connected with electric capacity C7, the resistance R5 of ground connection, and resistance R1 both ends are connected with metal-oxide-semiconductor V1 And the resistance R3 to be connected with metal-oxide-semiconductor V1, resistance R3 are connected with amplifier TLV3401U2 output end；Knot point in parallel is also associated with clamping Press diode Z2 and high magnetic conduction CT power takings are passed through by diode D2, diode D3, diode D4, diode D5, the rectifier bridge Sensor connects overhead transmission line.

Preferably, in addition to High Definition Systems clock and accessory system clock, the High Definition Systems clock include electric capacity C4, electric capacity C5 and crystal oscillator IZ1, electric capacity C4, electric capacity C5 are coupled with MSP430FR697xPM/RGC, and crystal oscillator IZ1 short circuits are in electric capacity Between C4, electric capacity C5；Accessory system clock includes electric capacity C9, electric capacity C10 and crystal oscillator IZ2, and electric capacity C9, electric capacity C10 are coupled with MSP430FR697xPM/RGC, crystal oscillator IZ2 short circuits are between electric capacity C9, electric capacity C10.

Preferably, in addition to Peripheral Interface unit；The Peripheral Interface unit is connected to by resistance R12 MSP430FR697xPM/RGC, it includes UART mouths, I2C, SPI and JATG interface.

Preferably, in addition to Peripheral Interface unit；The Peripheral Interface unit is connected to by resistance R12 MSP430FR697xPM/RGC, it includes UART mouths, I2C, SPI and JATG interface.

Preferably, the MCU, master synchronization and synchronous slave are using MSP430F6972 chips as control core.

Preferably, the MCU, master synchronization and synchronous slave are using MSP430F6972 chips as control core.

Compared with prior art, the beneficial effects of the utility model are：(1) the online power taking ability of current electric fields collecting unit By force, power taking electric current 5A can normal work；(2) the amplifier TLV3401 and MSP430FR697xPM/ of external electricity and interior power supply unit RGC coordinates, and realizes ± 1% high-acruracy survey electric current；(3) synchronous RF units enter under MSP430FR697xPM/RGC coordination Row work, when A, B, C of three-phase electricity are synchronized pair at interval of 5s and MCU, master synchronization, synchronous slave, realize three-phase synchronous Pair when precision reach ± 50 μ s；(4) realize between small current neutral grounding system earth fault, particularly instantaneity earth fault, complexity Having a rest property earth fault, high resistance earthing fault are accurately positioned；(5) complex fault process carries out backtracking inverting by recording waveform, Strong foundation is provided for accident analysis；(6) circuit abnormality sends early warning in advance.

Brief description of the drawings

Fig. 1 is the block diagram of the utility model；

Fig. 2 is the utility model MSP430FR697xPM/RGC schematic diagrames；

Fig. 3 is the utility model current electric fields collecting unit circuit diagram；

Fig. 4 is the utility model external electricity and interior power supply unit circuit diagram；

Fig. 5 is the utility model MSP430FR697xPM/RGC circuit diagrams；

Fig. 6 is electronic current mutual inductor output signal diagram under the input condition of the utility model zero；

Fig. 7 is the histogram of electronic current mutual inductor output signal under the input condition of the utility model zero；

Fig. 8 is that the utility model electronic current mutual inductor measures the linearity；

Fig. 9 is the utility model electronic current mutual inductor typical case's measurement error；

Figure 10 is that the utility model line status monitors, circuit maximum load current is less than 100A comparison result figures；

Figure 11 is the utility model Figure 10 histograms；

Figure 12 is the monitoring of the utility model line status, circuit maximum load current 100A~200A comparison result figures；

Figure 13 is the utility model Figure 12 histograms；

Figure 14 is that the utility model line status monitors, circuit maximum load current is more than 200A comparison result figures；

Figure 15 is the utility model Figure 14 histograms；

Figure 16 is zero-sequence current composite result figure when excitation surge current occurs in the utility model circuit；

Figure 17 is zero-sequence current composite result figure when two-phase transient earthing short circuit occurs encouraging in the utility model circuit；

Figure 18 is zero-sequence current composite result figure when multiple arc grounding occurs in the utility model circuit；

Figure 19 is the utility model small current neutral grounding one-phase earthing failure in electric distribution network procedure chart；

Figure 20 is distributed for the utility model small current neutral grounding one-phase earthing failure in electric distribution network high frequency transient zero sequence current signal Rule figure；

Figure 21 is the earth-free overhead line one-phase earthing failure in electric distribution network located instance figure of the utility model；

Figure 22 is the utility model artificial earthing's testing program figure；

The husky punchings of Figure 23 Figure 22 become circuit topological sum artificial earthing's trial position result figure；

Figure 24 is the recording oscillogram before and after the instant of failure of Figure 22 first times test monitoring point 1；

Figure 25 is the recording oscillogram before and after the instant of failure of Figure 22 first times test monitoring point 2；

Figure 26 is the recording oscillogram before and after the instant of failure of Figure 22 first times test monitoring point 3；

Figure 27 is the recording oscillogram before and after the instant of failure of Figure 22 first times test monitoring point 4；

Figure 28 is the recording oscillogram before and after the instant of failure of second of test monitoring point 1 of Figure 22；

Figure 29 is the recording oscillogram before and after the instant of failure of second of test monitoring point 2 of Figure 22；

Figure 30 is the recording oscillogram before and after the instant of failure of second of test monitoring point 3 of Figure 22；

Figure 31 is the recording oscillogram before and after the instant of failure of second of test monitoring point 4 of Figure 22；

Figure 32 is that the husky punching of the actual singlephase earth fault of the utility model becomes circuit topological sum singlephase earth fault positioning result Figure；

Figure 33 is the recording oscillogram before and after the instant of failure of the actual singlephase earth fault monitoring points 1 of Figure 32；

Figure 34 is the recording oscillogram before and after the instant of failure of the actual singlephase earth fault monitoring points 1 of Figure 32；

Figure 35 is the recording oscillogram before and after the instant of failure of the actual singlephase earth fault monitoring points 1 of Figure 32；

Figure 36 is the recording oscillogram before and after the instant of failure of the actual singlephase earth fault monitoring points 1 of Figure 32.

Embodiment

Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the embodiment of the utility model is carried out Clearly and completely describing, it is clear that described embodiment is only the utility model part of the embodiment, rather than whole Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made The every other embodiment obtained, belong to the scope of the utility model protection.

Fig. 1~36 are referred to, the utility model provides a kind of technical scheme：

A kind of transient state recording indicator, including MSP430FR697xPM/RGC, current electric fields collecting unit and outside take Electric and interior power supply unit, the current electric fields collecting unit include electronic current collector, one end of the electronic current collector Amplifier LMV611U (3,4) pin, other end power taking, short circuit resistance R between amplifier LMV611U (Isosorbide-5-Nitrae) pin are connected, and 1 draws Pin simultaneously meets two identical amplifier LMV61U1；Short circuit is by electric capacity R and electric capacity C parallel connections between amplifier LMV61U1 (Isosorbide-5-Nitrae) pin RC circuits, its 1 pin be connected to MSP430FR697xPM/RGC by I1, I2 respectively, amplifier LMV611U, amplifier LMV61U1 2 pins are grounded, and 5 pins are respectively grounded by the electric capacity C of three same sizes；

External electricity and interior power supply unit include voltage-regulator diode Z3 and transient supression diode Z4 in parallel, its other end It is grounded respectively, simultaneously tie-point meets MSP430FR697xPM/RGC for it, while also passes through resistance R1, diode D1, resistance R2 connections To amplifier TLV3401U2 3 pins, amplifier TLV3401U2 3 pins are also connected with electric capacity C7, the resistance R5 of ground connection, resistance R1's Both ends are connected with metal-oxide-semiconductor V1 and the resistance R3 to be connected with metal-oxide-semiconductor V1, amplifier TLV3401U2 2 pins ground connection, and 4 pins connect MSP430FR697xPM/RGC V_REF ends, 5 pins are grounded by electric capacity C6, resistance R3 and amplifier TLV3401U2 output end Connection, metal-oxide-semiconductor V1 one end ground connection；Knot point in parallel is also associated with clamping diode Z2 and by diode D2, diode D3, two Pole pipe D4, diode D5, clamping diode Z2 one end ground connection, one end ground connection of rectifier bridge, the rectifier bridge pass through high magnetic conduction CT Power taking sensor connects overhead transmission line.

Also include High Definition Systems clock and accessory system clock, the High Definition Systems clock includes electric capacity C4, electric capacity C5 and crystal oscillator IZ1, electric capacity C4, electric capacity C5 are coupled with MSP430FR697xPM/RGC, and crystal oscillator IZ1 short circuits are in electric capacity C4, electric capacity Between C5；Accessory system clock includes electric capacity C9, electric capacity C10 and crystal oscillator IZ2, and electric capacity C9, electric capacity C10 are coupled with MSP430FR697xPM/RGC, crystal oscillator IZ2 short circuits are between electric capacity C9, electric capacity C10.

Also include synchronous RF units, the synchronous RF units are connected to MSP430FR697xPM/RGC, and it includes MCU, the MCU It is connected with master synchronization serial communication, master synchronization radio communication connects synchronous slave, and synchronous slave connects with MCU serial communications Connect.

Also include Peripheral Interface unit；The Peripheral Interface unit is connected to MSP430FR697xPM/RGC by resistance R12, It includes UART mouths, I2C, SPI and JATG interface.

The MCU, master synchronization and synchronous slave are using MSP430F6972 chips as control core.

The online power taking ability of current electric fields collecting unit is strong, and power taking electric current 5A can normal work；External electricity and interior power supply The amplifier TLV3401 and MSP430FR697xPM/RGC of unit coordinate, and realize ± 1% high-acruracy survey electric current；Synchronous RF is mono- Member is operated under MSP430FR697xPM/RGC coordination, and A, B, C of three-phase electricity are at interval of 5s and MCU, master synchronization, together When step slave synchronizes pair, precision reaches ± 50 μ s when realizing three-phase synchronous pair；Small current neutral grounding system earth fault is realized, Particularly instantaneity earth fault, complicated intermittent grounding fault, high resistance earthing fault are accurately positioned；Complex fault process is led to Cross recording waveform and carry out backtracking inverting, strong foundation is provided for accident analysis；Circuit abnormality sends early warning in advance.

Current electric fields collecting unit, CPU are MSP430FR697xPM/RGC, synchronous RF units, high accuracy system Clock of uniting provides power supply by outer external electricity and interior power supply unit, and High Definition Systems clock provides stable for CPU Work schedule and precision clock, current electric fields collecting unit and synchronous RF units are carried out under the coordination of CPU Work, when synchronous pair when three-phase alternating current A, B, C three-phase synchronizing pair at interval of 5s and MCU, master synchronization, synchronous slave. Current electric fields collecting unit takes current electric fields data to be transferred to CPU, is analyzed through CPU, arranges MCU is transferred to by RF synchronization units afterwards.

In order to preferably pick up distribution network line current signal, line status monitor is surveyed using electronic current mutual inductor It is high magnetic conduction CT power taking sensors to measure electric current.Electronic current mutual inductor has low noise, high linearity, high accuracy and high band The characteristics of wide.

In order to the transient current signal on accurate recording distribution network line, line status monitor uses 4KHz sample rates Line current signal is acquired, signal of the bandwidth within 2KHz can be recorded.

Instantaneous front and rear line current and line-to-ground electric field waveform, line status monitoring occurs in order to record failure Device is used as trigger condition using current break and electric field mutation, starts recording.

In order to obtain zero-sequence current on overhead line, line status monitor is by carrying out high-precise synchronization between three-phase Pair when, the three-phase current signal of passage time precise synchronization directly superposition generates zero-sequence current, and time synchronization error can be controlled System is within ± 50us, and three-phase phase angle error is at ± 0.9 °.

Line status monitor power unit includes automatic electricity getting main power source and reserve battery two parts form, and passes through power supply pipe Reason switches over.Automatic electricity getting main power source is by power taking CT and power control section packet into for from magnetic field caused by line current Obtain energy；Problems be present in traditional CT power takings：

(1) power that line current hour power taking CT is got is inadequate；

(2) power taking CT saturations when line current is big, output voltage is high, power taking inclement condition；

(3) power taking CT is easily damaged during Short-Circuit High Current.

Line status monitor automatic electricity getting main power source solves the above problems in the following way：

(1) special power taking CT is designed, the ability for obtaining energy from magnetic field caused by line current is strong, efficiency high, and And volume is smaller；

(2) line current hour, enough power can be got by Power Control, it is only necessary to 10 amperes of line currents, so that it may To support distribution network line state monitor global function normal work；

(3) when line current is big, by Power Control power taking CT can be made unsaturated, improves power taking condition, remain able to take To the energy of abundance；

(4) during Short-Circuit High Current, power taking can be stopped rapidly by Power Control, avoid power taking CT under huge current flow impact Damage.

When automatic electricity getting main power source power taking power is enough, line status monitor uses automatic electricity getting main power source as power supply electricity Source；When automatic electricity getting main power source power taking power is inadequate, line status monitor uses reserve battery as power supply as benefit Fill, reserve battery normal working voltage 3.6V, capacity reaches 8Ah, can be worked three months with distribution network line status monitor.

When electric current to be measured is zero, for electronic current mutual inductor, optimally output should also be zero, But actually because electronic current mutual inductor noise in itself and the intrinsic quantizing noises of ADC, electronic current mutual inductor are defeated Go out to be not zero, output signal determines resolution capability of the electronic current mutual inductor to electric current under this zero input condition.

Electronic current mutual inductor output signal under typical zero input condition is shown refering to Fig. 6.In this implementation Example further part, unless otherwise specified, for current signal, transverse axis is sampled point sequence number on figure, sample rate 4kHz, and the longitudinal axis is Current value, unit A.

The original sample value of electronic current mutual inductor output signal does histogram analysis under zero input condition, refering to Fig. 7, It can be found that approximate normal distribution is presented in the distribution of original sample value, and it is an approximate zero-mean normal distribution, this explanation electronic type Current transformer noise in itself and the intrinsic quantizing noises of ADC, close to white noise.Electronic current mutual inductance under zero input condition The variance of device output signal is 0.28A or so, and this numerical value reflects the online recording monitor electronic current mutual inductance of power distribution network The outstanding electric current resolution capability of device.

Using the electronic current mutual inductor of the online recording monitor of power distribution network, following current value alternating current is measured： 20A, 25A, 30A, 200A, 300A, 400A, 500A, 600A, 700A, one typical relations between measured value and actual value Refering to Fig. 8, corresponding measurement error refers to Fig. 9.It can be found that electronic current mutual inductor has the higher measurement linearity, and And accuracy class can reach 1 grade.

Line status monitor is arranged near overhead line on-pole switch, had with electronic current mutual inductor line current Measurement Result of Current Transformer compares in valid value measurement result and on-pole switch, as a result as follows：

1. circuit maximum load current is less than 100A；In Guo Wang Pinggu County, beijings electric company Shandong village Zhan Beitun roads 2 bar The line status monitor of preceding installation and 224 switch load current measurement value comparison results of Shandong village station north village refer to Figure 10.Mountain The bar line status monitor (2. locating line in Figure 10) of Dong Zhuan Zhan Beitun roads 2 and switching current measurement result basic trend keep same Step, error are distributed as normal distribution, mean error 1.1A, and the reason for causing this random error is because during both measurements Between synchronous error in second level.Using Y-axis origin as reference：The line of proximity values 30 is the bar circuit of Shandong village Zhan Beitun roads 2, proximity values 20 line is the switch of Shandong village station north village 224.

2. circuit maximum load current 100A~200A；In Guo Wang Pinggu County, beijings electric company exit of valley Zhan Xiying roads 2 bar The load current measured value comparison result of the line status monitor of preceding installation and the switch of exit of valley station west battalion 215 refers to Figure 11.Valley Line status monitor (i.e. 1. locating line in Figure 12) and switching current measurement result basic trend are kept before the bar of Kou Zhanxiying roads 2 Synchronous, error is distributed as normal distribution, mean error 1.1A.Using Y-axis origin as reference：The line of proximity values 100 is exit of valley station The switch of west battalion 215, the line of proximity values 110 is circuit before the bar of exit of valley Zhan Xiying roads 2.

3. circuit maximum load current is more than 200A；

The line status monitor and gold installed before the bar of Guo Wang Pinggu County, beijings electric company Golden Sea Lake Zhan Dulehe roads 2 The load current measured value comparison result that Hai Hu Zhan Dule rivers 213 switch refers to Figure 12.The bar front of Golden Sea Lake Zhan Dulehe roads 2 Line state monitor (i.e. 1. locating line in Figure 14) and switching current measurement result basic trend keep synchronous, and error is distributed as normal state Distribution, mean error is -1.9A.Using Y-axis origin as reference：The line of proximity values 60 is that solely happy river 213 switchs at Golden Sea Lake station, is approached The line of value 80 is circuit before the bar of Golden Sea Lake Zhan Dulehe roads 2.

By above-mentioned test result, it can be found that measurement accuracy and reality of the electronic current mutual inductor to live line current Room test result is tested to approach.

Three-phase line state monitor synthesizes zero-sequence current result, further illustrates three-phase electronic current transformer Uniformity and three-phase line state monitor timing tracking accuracy, test are as follows：

1. there is zero-sequence current composite result during excitation surge current in circuit；

Refering to Figure 16, be worth segment along X-direction 0~50 in figure, represented respectively close to X-axis, on X-axis, under X-axis A, B, C three-phase currents, it is 3 times of zero-sequence current 3I0 along X-direction line, transverse axis is sampled point sequence number, sample rate 4kHz, and the longitudinal axis is Electric current, unit A.It can be found that although occurring the excitation surge current of waveform Severe distortion on circuit, but due to being earth-free Power distribution network, zero-sequence current should still be approximately 0.

2. there is zero-sequence current composite result during two-phase transient earthing short circuit in circuit；

Refering to Figure 17 (meaning and the same Figure 16 of parameter), it is worth in figure along X-direction 0, is worth under X-axis, on X-axis away from 0, X A, B, C three-phase current are represented respectively close to 0 value on axle, it can be found that when circuit is normal, due to being earth-free power distribution network, zero Sequence electric current is 0, but when two-phase transient earthing short circuit occurs in circuit, zero-sequence current is not 0, obvious exception occurs, and After subsequent two-phase grounding fault disappears, zero-sequence current reverts to 0 again.

3. there is zero-sequence current composite result during two-phase transient earthing short circuit in circuit；

Refering to Figure 18 (meaning and the same Figure 16 of parameter), be worth in figure along X-direction 0, on X-axis away from 0 value, under X-axis, X A, B, C three-phase current are represented respectively close to 0 value on axle, it can be found that when circuit is normal, due to being earth-free power distribution network, zero Sequence electric current is 0, but when multiple arc grounding occurs in circuit, circuit occurs every time because ungrounded phase overvoltage causes to insulate When breakdown produces arc discharge, zero-sequence current is not 0, obvious exception occurs, after arc discharge disappears, due to being not connect Ground power distribution network, there is the power frequency zero-sequence current of a very little on circuit.

By above-mentioned zero-sequence current waveform example, illustrate that three-phase line state monitor can be by the electricity of high consistency Type current transformer and precise synchronization, obtain the zero-sequence current of overhead line.

Residual voltage and zero sequence current signal during small current neutral grounding one-phase earthing failure in electric distribution network refer to Figure 19.Tool Body process is as follows：

(1) before singlephase earth fault generation, residual voltage u0 and zero-sequence current i0 are 0；

(2) moment occurs in failure, rises because the phase ground voltage of Earth Phase falls with the phase ground voltage of ungrounded phase, meeting Produce an amplitude and be not 0 power frequency residual voltage, while can also produce the transient high frequency zero-sequence current that an amplitude is It, hold The continuous time is very short, is usually no more than 20ms；

(3) after about 20ms transient process, system enters steady-state process, relative to transient high frequency zero-sequence current Amplitude It, stable state power frequency zero-sequence current amplitude Is very littles.

By above-mentioned singlephase earth fault detailed process, it is known that in order to accurately detect positioning small current neutral grounding power distribution network Singlephase earth fault, it is preferably to use transient high frequency zero sequence current signal.Sent out simultaneously according to theory analysis and live recording result It is existing, caused high frequency transient zero sequence current signal during small current neutral grounding power distribution network single-phase earthing, there is point refering to Figure 20 Cloth rule：

(1) non-fault line is different with the high frequency transient zero sequence current signal of faulty line；

(2) it is different with the high frequency transient zero sequence current signal behind trouble point before trouble point on faulty line.

Intelligent power distribution rack ceases to be busy line state monitoring system is exactly to carry out phase-to-ground fault detection according to above-mentioned rule Positioning, detailed process are as follows：

1. monitoring point line status monitor triggers recording；

When singlephase earth fault occurs, the phase ground voltage of Earth Phase falls, and causes phase earth electric field also to fall, ungrounded phase The rise of phase ground voltage, cause phase earth electric field also to raise, while high frequency transient current can be produced in Earth Phase and ungrounded phase, These anomalous variations can trigger line status monitor recording.

2. obtain each monitoring point high frequency transient zero sequence current signal

The three-phase line state monitor time of each monitoring point is synchronous, so can obtain each prison by processing The zero sequence current signal of measuring point, it can also further obtain high frequency transient zero sequence current signal.

3. networking analysis of high frequency transient zero-sequence current signal

Refering to Figure 20 regularity of distribution of the high frequency transient zero sequence current signal on distribution network line, it is possible to carry out single-phase The detection positioning of earth fault, orients the section which two monitoring point trouble point is located between.

It is big in Pinggu in the intelligent power distribution rack ceases to be busy line state monitoring system of Guo Wang Pinggu County, beijings electric company installation Huashan Zhan Liudian roads successfully located once due to earth fault caused by insulator failure.The circuit uses earth-free side Formula, 7 complete equipments are mounted with altogether on circuit, moment occurs in earth fault, 7 complete equipments have recorded the ripple before and after instant of failure Shape.Refering in Figure 21, the waveform top of each monitoring point is zero-sequence current, and bottom is three-phase electric field, A, B, C three-phase, is passed through Can clearly it be found refering to Figure 18, C phase electric fields fall, and Earth Phase is C phases, while the zero-sequence current phase of monitoring point 2~7 Seemingly, it is dissimilar with monitoring point 1, can be occurred with positioning both ground failure between monitoring point 1~2, after confirm by line walking.

In the intelligent power distribution rack ceases to be busy line state monitoring system of south net Guizhou Kweiyang south of a city power supply administration installation, carry out Artificial earthing tests twice, for test system for positioning through grounding through arc overhead line one-phase earthing failure in electric distribution network Whether principle is feasible, in subsequent running, successfully positions a singlephase earth fault again, and guides O＆M teams and groups to look for Earth fault is excluded to earth fault.

1. time artificial earthing's experiment for the first time

Become refering to Figure 22 artificial earthings experiment in the husky punching of Guiyang south of a city power supply administration in husky line transfer and carry out, use husky line transfer 26 Branch line C phase lines are as ground wire.The husky upper load of line transfer 26 is less, and all loads are cut by disconnecting link during test for ground Remove, using the on-pole switch installed on 26 No. 8 bars, carry out artificial earthing and excision.First time artificial earthing experiment is adjusted in sand Used on No. 10 bars of line 26Skin aluminum steel, C phase conductors are directly connected to insulator and fix cross-arm, short circuit C phase insulators To simulate singlephase earth fault.

Whole husky punching becomes line topological and refers to Figure 23, and system includes 20 monitoring points, and artificial earthing's point is in monitoring point 2,3 Between, the waveform of monitoring point 1~4 is have selected, refering to Figure 24~27, for illustrating that system single-phase earth fault detection positioning is former Reason.

Each monitoring point recording waveform top half is current waveform, and the latter half is normalization electric field, and transverse axis is sampling Point sequence number, sample rate 4kHz, current waveform longitudinal axis unit is A, wherein, Figure 24, (a) using Y-axis origin as reference, 0 value line is zero Sequence, it is C phases close to 50 value lines, is A phases close to 80 value lines, close -100 value line is B phases；Wherein, Figure 25, (b) using Y-axis origin as With reference to 0 value line is zero sequence, is C phases close to 0 value line, is A phases close to 80 value lines, and close -100 value line is B phases；Wherein, Figure 26, (c) using Y-axis origin as reference, 0 value line is zero sequence, is A phases close to 0 value line, is B phases close to 20 value lines, and close -40 value line is C Phase；Wherein, Figure 27, (d) using Y-axis origin as reference, 0 value line is zero sequence, is C phases close to 1000 value lines, is B close to 150 value lines Phase, close -220 value line is A phases.Figure 24~27 clearly demonstrate the regularity of distribution of high frequency transient zero-sequence current on the line：

(1) monitoring point 1 and monitoring point 2 are located on failure path, and both recording waveforms are closely similar；

(2) monitoring point 2 and monitoring point 3 are located at before and after trouble point respectively, and both recording different wave shapes are very big；

(3) monitoring point 1 and monitoring point 4 are located on faulty line and non-fault line respectively, and both recording different wave shapes are non- Chang great.

2. second of artificial earthing's experiment

Second of artificial earthing's experiment uses on husky No. 10 bars of line transfer 26Skin aluminum steel, C phase conductors are passed through one Root branch is connected to insulator and fixes cross-arm, simulates singlephase earth fault caused by tree line.Artificial earthing's point is in still monitoring point 2nd, between 3, the waveform of monitoring point 1~4 is still have selected, refering to Figure 28~31, clearly illustrates high frequency transient zero sequence again The regularity of distribution of electric current on the line.

3. the actual singlephase earth fault of third time

Actual singlephase earth fault positioning result refers to Figure 32 for the third time, and singlephase earth fault earth point is in monitoring point 2,3 Between, intelligent power distribution rack ceases to be busy line state monitoring system sends an SMS to O＆M teams and groups, confirms trouble point through line walking on the spot The reason for positioning successfully, triggering singlephase earth fault is that user transformers insulation damages cause single-phase earthing.

The recording waveform of monitoring point 1~4 in Figure 32 is shown refering to Figure 33~36, illustrates actual track singlephase earth fault During, the regularity of distribution of high frequency transient zero-sequence current on the line is consistent with principle.

While there has been shown and described that embodiment of the present utility model, for the ordinary skill in the art, It is appreciated that these embodiments can be carried out with a variety of changes in the case where not departing from principle of the present utility model and spirit, repaiied Change, replace and modification, the scope of the utility model are defined by the appended claims and the equivalents thereof.

Claims (5)

1. a kind of transient state recording indicator, including MSP430FR697xPM/RGC, current electric fields collecting unit and external electricity And interior power supply unit, it is characterised in that：The current electric fields collecting unit includes electronic current collector, electronic current collection One end connection amplifier LMV611U (3,4) pin of device, short circuit resistance R between amplifier LMV611U (Isosorbide-5-Nitrae) pin, and 1 pin And meet two identical amplifier LMV61U1；Short circuit is by RC in parallel electric capacity R and electric capacity C between amplifier LMV61U1 (Isosorbide-5-Nitrae) pin Circuit, its 1 pin are connected to MSP430FR697xPM/RGC by I1, I2 respectively；

External electricity and interior power supply unit include voltage-regulator diode Z3 and transient supression diode Z4 in parallel, and simultaneously tie-point connects for it MSP430FR697xPM/RGC, while be also connected to the 3 of amplifier TLV3401U2 by resistance R1, diode D1, resistance R2 and draw Pin, amplifier TLV3401U2 3 pins are also connected with electric capacity C7, the resistance R5 of ground connection, resistance R1 both ends be connected with metal-oxide-semiconductor V1 and The resistance R3 to be connected with metal-oxide-semiconductor V1, resistance R3 are connected with amplifier TLV3401U2 output end；Knot point in parallel is also associated with pincers pressure Diode Z2 and sensed by diode D2, diode D3, diode D4, diode D5, rectifier bridge by high magnetic conduction CT power takings Device connects overhead transmission line.

A kind of 2. transient state recording indicator according to claim 1, it is characterised in that：Also include High Definition Systems clock with And accessory system clock, the High Definition Systems clock include electric capacity C4, electric capacity C5 and crystal oscillator IZ1, electric capacity C4, electric capacity C5 connect respectively To MSP430FR697xPM/RGC, crystal oscillator IZ1 short circuits are between electric capacity C4, electric capacity C5；Accessory system clock includes electric capacity C9, electricity Hold C10 and crystal oscillator IZ2, electric capacity C9, electric capacity C10 are coupled with MSP430FR697xPM/RGC, crystal oscillator IZ2 short circuits electric capacity C9, Between electric capacity C10.

A kind of 3. transient state recording indicator according to claim 1, it is characterised in that：Also include synchronous RF units, this is same Step RF units are connected to MSP430FR697xPM/RGC, and it includes MCU, and the MCU is connected with master synchronization serial communication, synchronous main Machine radio communication connects synchronous slave, and synchronous slave is connected with MCU serial communications.

A kind of 4. transient state recording indicator according to claim 1, it is characterised in that：Also include Peripheral Interface unit；Should Peripheral Interface unit is connected to MSP430FR697xPM/RGC by resistance R12, and it includes UART mouths, I2C, SPI and JATG connect Mouthful.

A kind of 5. transient state recording indicator according to claim 3, it is characterised in that：The MCU, master synchronization and same Slave is walked using MSP430F6972 chips as control core.