CN106771647A - A kind of low current neutral grounding electric network capacitance current measurement method - Google Patents

A kind of low current neutral grounding electric network capacitance current measurement method Download PDF

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Publication number
CN106771647A
CN106771647A CN201611264176.3A CN201611264176A CN106771647A CN 106771647 A CN106771647 A CN 106771647A CN 201611264176 A CN201611264176 A CN 201611264176A CN 106771647 A CN106771647 A CN 106771647A
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China
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current
low
measurement
capacitance
pressure
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CN201611264176.3A
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Inventor
仝新宇
王永杰
李建伟
宋兴旺
徐笑天
陈向东
杨乔川
沈妍
孙明军
赵宇
王鑫
吴杰
李晓永
李昕
王云昊
岳洋
刘祚安
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State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
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State Grid Corp of China SGCC
State Grid Tianjin Electric Power Co Ltd
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Priority to CN201611264176.3A priority Critical patent/CN106771647A/en
Publication of CN106771647A publication Critical patent/CN106771647A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/25Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/26Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
    • G01R27/2605Measuring capacitance

Abstract

The present invention relates to a kind of low current neutral grounding electric network capacitance current measurement method, including the type Capacitive current testers of HC 1 and measurement apparatus, the type Capacitive current testers of HC 1 inject 5Hz constant current square-wave signals to power distribution network zero sequence loop, discharge and recharge is carried out to line mutual-ground capacitor, so as to be measured to power distribution network ground capacity electric current, measurement apparatus are by handing over, DC power system, digital signal microprocessor, signal gathering unit and power electronic circuit.capacitor are constituted, digital signal microprocessor control power electronic circuit.capacitor produces a constant current 5Hz square-wave signals, by system busbar open delta, ground connection becomes the zero sequence loop of neutral point or capacitor bank neutral point injected system, signal acquiring system uses high-performance A/D sampling circuits and Digital Signal Processing.

Description

A kind of low current neutral grounding electric network capacitance current measurement method
Technical field
The invention belongs to power system measuring field, especially a kind of low current neutral grounding electric network capacitance current measurement method.
Background technology
In China, low and medium voltage distribution network line fault is mostly singlephase earth fault.Due to using isolated neutral side Formula is run, and line voltage vector triangle is constant during singlephase earth fault, and three phase-to-neutral voltages are constant.In electric network capacitance and current Less, ground arc can under conditions of self-extinguishment, power network can tape jam continue to power 1~2 hour.Therefore, in China's early stage Use earth-free mode more low-voltage network, improve the reliability and continuity of power supply.With the fast development of urban construction, city Utility grid is increasingly employed cable run, greatly increases the capacitance current of power network.According to statistics, the short trouble of power distribution network Much due to circuit single-phase-to-ground current cannot self-extinguish cause, when single-phase-to-ground current is more than code defined When " 10kV and 35kV system capacitive currents are respectively greater than 30A and 10A ", a kind of unstable intermittent ground arc will be produced, Cause the arc grounding over-voltage that amplitude is higher.The arc overvoltage duration is long, influence area big, poor to being insulated in power network Equipment and circuit on insulation weak-point, insulation breakdown may be caused, make failure propagation.Further, since neutral point is unstable, Power network single-phase earthing easily trigger EMR electromagnetic resonance and cause voltage transformer burn with the accident such as high-voltage wire iron-melting fusing, to power network Safe and reliable operation brings greatly harm.
Traditional capacitance current measurement method can be divided into direct method and indirect method.
The direct method of measurement such as Single Phase Metal ground connection method, in more early period, measurement capacitance current is typically connect using Single Phase Metal Ground method, this method is exactly to be operated using a breaker, and distribution line is artificially carried out into single phase grounding test, Ran Houtong Overcurrent transformer direct measurement enters the capacitance current on ground.The operation and wiring that this method needs are very numerous and diverse, and have can The insulation that ungrounded phase insulation weakness can be jeopardized causes two differently short-circuit, very dangerous.Whole experiment work is to experiment people The safety of member and power network constitutes a threat to, and the danger of experiment is very big.
The method that presently, there are various indirect measurement electric network capacitance and currents, according to whether directly contact primary side, can divide It is two major classes:The additional capacitance method of the first kind such as neutral point, directly must come into contacts with measurement process with primary side;Equations of The Second Kind is as noted Enter signal injection method, because being to be injected by PT open deltas and measurement feedback signal in real time in measurement process, so need not be with Primary side directly contact.The indirect measurement that the current adopted additional capacitance method of such as neutral point must directly come into contacts with primary side Method, although easier than direct method, and capacitance current value can be accurately measured, but still have the disadvantage that:When 1. measuring Still come into contacts with primary side, personnel cannot ensure with equipment safety.2. it is cumbersome due to primary equipment to be related to, together When there is also the danger of maloperation.Time-consuming for preparation, measures inefficiency.The usual most of the time is expended and is waiting tune Drag out a miserable existence and make, open work ticket, grid switching operation, do safety measure.Two to three stations can only be surveyed within one day, operating efficiency is very low.Due to Above-mentioned two reason, it is desirable to have a kind of equipment can directly in the capacitance current of secondary side measuring system, it is not necessary to is related to danger Primary side;Cumbersome grid switching operation and wait is not needed, and makes the measurement work of capacitance current easy, efficient, easy.Need not In the capacitance current measurement method of primary side directly contact, according to the difference that required calculating signal is originated, two classes are broadly divided into: The essential idea of the first kind be using power network normally run when neutral point displacement voltage, neutral point current and arc suppression coil electricity The parameters such as inductance value, are calculated the capacitive reactance total over the ground of power network;Zero sequence loop when then by single-phase fault, calculates current operation side Capacitance current under formula.Equations of The Second Kind is then injecting signal, that is, utilize the feedback signal of the non-power-frequency current from the extraneous injection of system, By corresponding equivalent circuit, capacitor current for earthing is calculated.
The more commonly used method includes three frequency methods and frequency dividing method in signal moves in method, but three frequency methods may be only available for circuit The less situation of direct-to-ground capacitance, when electric capacity is larger, measurement demand can not be all met with three frequency methods anyway.Frequency dividing Method has large increase compared to three frequency method stability, but when smaller capacitive is measured, it is whole when Injection Signal frequency is relatively low The impedance of individual RLC series loops can be very big, and the excitation impedance with PT is more or less the same, and very big measurement can be caused in this case Error, so when smaller capacitive is measured, frequency dividing method occurs larger error.
The content of the invention
It is an object of the invention to overcome the deficiencies in the prior art part, there is provided a kind of based on the small of square-wave signal injection method Current earthing electric network capacitance and current measuring method.
The present invention solves its technical problem and takes following technical scheme to realize:
A kind of low current neutral grounding electric network capacitance current measurement method, including HC-1 types Capacitive current tester and measurement are filled Put, HC-1 types Capacitive current tester injects 5Hz constant current square-wave signals to power distribution network zero sequence loop, and line mutual-ground capacitor is carried out Discharge and recharge, so as to be measured to power distribution network ground capacity electric current, measurement apparatus are micro- by AC and DC power-supply system, data signal Processor, signal gathering unit and power electronic circuit.capacitor composition, digital signal microprocessor control electronic power inversion electricity Road produces a constant current 5Hz square-wave signals, and neutral point or capacitor bank neutral point are become by system busbar open delta, ground connection The zero sequence loop of injected system, signal acquiring system uses high-performance A/D sampling circuits and Digital Signal Processing.
And, the HC-1 types Capacitive current tester is connected to system under test (SUT) bus PT and opens for bis- times by Special cable wire Mouth triangle.
And, the HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then leads to Cross insulating bar and the supporting PT primary sides of instrument are connected to grounding transformer neutral point.
And, the HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, The supporting PT primary sides of instrument are connected by a compensation capacitor group by insulating bar again.
And, in PT low-pressure sides injection constant current i0, then have electric current i in PT high-pressure sides1, i2, i3, PT exciting currents ia, ib, icIf PT high-low pressure umber of turns are respectively n1, n2Then there is following relation:
n1(i1-ia)=n2i0
n1(i2-ib)=n2i0
n1(i3-ic)=n2i0
And, after Injection Signal is for the constant current square-wave signal of 5Hz, the signal to injecting carries out Fourier transformation and signal Analysis.For the square-wave signal that injects by the deployable sine wave sum different into angular frequency of fourier series, i.e.,:
Sampling is carried out in voltage transformer secondary open delta and data processing respectively obtains U5, U15, U25And I5, I15, I25 Then have:
Signal to injecting carries out calculating analysis, so as to obtain the size of system capacitive current.
And, the HC-1 types Capacitive current tester is connected to system under test (SUT) bus PT and opens for bis- times by Special cable wire In the circuit of mouth triangle, including:HC-1 types Capacitive current tester, band fuse insulating bar, grounding transformer, arc suppression coil and mother Line transformer, wherein busbar transformer low-pressure side delta connection, arc suppression coil are exited, and HC-1 type Capacitive current testers are to instrument The supporting special PT low-pressure sides of device inject the constant current square-wave signal of 5Hz, red clip is connect into a ends black clip and connects x ends special PT low-pressure sides form loop, and snap into grounding transformer neutral point and circuit pair by the insulating bar with fuse in PT high-pressure sides Ground electric capacity forms loop, by carrying out Fourier space decomposition and PT low-pressure sides supporting to instrument electricity to the square-wave signal being input into Pressure and current measurement, calculate the ground capacitance of circuit, and then obtain capacitance current.
And, the HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then leads to Cross insulating bar the supporting PT primary sides of instrument are connected in the circuit of grounding transformer neutral point, including:HC-1 type capacitance currents Tester, band fuse insulating bar, compensation capacitor group, arc suppression coil and busbar transformer, wherein busbar transformer low-pressure side three Angular connection, arc suppression coil is exited.HC-1 types Capacitive current tester red clip is connect into a ends black clip and connects x ends special PT low-pressure sides form loop, and snap into capacitor bank neutral point and line-to-ground by the insulating bar with fuse in PT high-pressure sides Electric capacity forms loop, and Fourier space decomposition and PT low-pressure side voltages supporting to instrument are carried out by the square-wave signal being input into And current measurement, the ground capacitance of circuit is calculated, compensating electric capacity amount is then subtracted according to reduction formula, obtain real electric capacity Amount, and then obtain capacitance current.
And, the HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, During the supporting PT primary sides of instrument are connected into the circuit of a compensation capacitor group by insulating bar again, including:HC-1 type capacitance currents Tester, band fuse insulating bar, compensation capacitor group, arc suppression coil and busbar transformer, wherein busbar transformer low-pressure side three Angular connection, secondary resonance elimination device disconnects, high resistant resonance eliminator short circuit.HC-1 types Capacitive current tester red clip is connect into L ends Black clip connect N-terminal special PT low-pressure sides formed loop, by be input into square-wave signal carry out Fourier space decompose with And PT low-pressure side voltages supporting to instrument and current measurement, the ground capacitance of circuit is calculated, and then obtain capacitance current.
Advantages and positive effects of the present invention are:
The advantage of the invention is that for the power distribution network of different voltage class, special single-phase potential transformer customized subtracts Few influence of the exciting current to capacitance current measurement precision;Injection Signal is the constant current square-wave signal of 5Hz, and the signal to injecting enters Row Fourier transformation and signal analysis, by the zero sequence loop of the voltage transformer secondary injected system of system, signal acquisition system System uses high-performance A/D sampling circuits and Digital Signal Processing, and the signal to injecting carries out calculating analysis, so as to obtain system electricity The size of capacitance current;Square-wave signal injection method is more beneficial for reducing influence of the imbalance of three-phase voltage to certainty of measurement;The method Multi-signal injection mode, the i.e. injection of grounding transformer neutral point, the injection of compensation capacitor neutral point and bus PT can be used to open Mouth triangle injection;The method only needs an external voltage transformer and the insulating bar with fuse, it is not necessary to add optional equipment And instrument, and can power network normally run when measure, and do not change power network wiring, can safely, fast and accurately measure and be System capacitance current value.
Brief description of the drawings
Fig. 1 is schematic block circuit diagram of the invention;
Fig. 2 is to measure wiring diagram using bus open delta PT injection methods in the present invention;
Fig. 3 is to measure wiring diagram using grounding transformer neutral point injection method in the present invention;
Fig. 4 is to measure wiring diagram using compensation capacitor group neutral point injection method in the present invention.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings and by specific embodiment, and following examples are descriptive , it is not limited, it is impossible to which protection scope of the present invention is limited with this.
A kind of low current neutral grounding electric network capacitance current measurement method, its test philosophy is shown in Fig. 1, main to include several portions Point:HC-1 types Capacitive current tester, the supporting PT of instrument, band fuse insulating bar, grounding transformer, capacitor bank, bus PT, its Median generatrix PT open-delta connections, system arc suppression coil is exited, and HC-1 types Capacitive current tester is connected by Special cable wire It is connected to bis- open deltas of system under test (SUT) bus PT, or tester private cable is connected to the secondary side of the supporting PT of instrument, then The supporting PT primary sides of instrument are connected to by compensation capacitor group (or grounding transformer) neutral point by insulating bar, by above-mentioned Anticipate a kind of mode, HC-1 types Capacitive current tester injects 5Hz constant current square-wave signals to power distribution network zero sequence loop, to line-to-ground Electric capacity carries out discharge and recharge, so as to be measured to power distribution network ground capacity electric current.
Using the special PT of capacitance current measurement
In PT low-pressure sides injection constant current i0, then have electric current i in PT high-pressure sides1, i2, i3, PT exciting currents ia, ib, ic, If PT high-low pressure umber of turns are respectively n1, n2Then there is following relation:
n1(i1-ia)=n2i0
n1(i2-ib)=n2i0
n1(i3-ic)=n2i0
Generally it is believed that due to excitation impedance > > winding resistances R, excitation impedance > > leakage reactances XL, excitation impedance > > capacitive reactances XC, so ia=ib=ic=0, i.e. i1=i2=i3.But i in a practical situationa≠ib≠icThe exciting current of ≠ 0, PT Can have a significant impact to the error that we measure, particularly the number of turn of winding can also be impacted to our accuracies of measurement. In this case, we suitably have adjusted the number of turn and canoe of PT windings, effectively reduce exciting current to electric capacity electricity The influence of flow measurement precision.
Injection Signal is the constant current square-wave signal of 5Hz
Injection Signal is the constant current square-wave signal of 5Hz, and the signal to injecting carries out Fourier transformation and signal analysis.For The square-wave signal of injection by the deployable sine wave sum different into angular frequency of fourier series, i.e.,:
Sampling is carried out in voltage transformer secondary open delta and data processing respectively obtains U5, U15, U25And I5, I15, I25 Then have:
Microprocessor can accurately obtain capacitance C by solving equations, so as to calculate capacitance current numerical value.Measurement apparatus Theory diagram as shown in figure 1, the device it is main by AC and DC power-supply system, digital signal microprocessor, signal gathering unit and Power electronic circuit.capacitor etc. is constituted.
Digital signal microprocessor control power electronic circuit.capacitor produces a constant current 5Hz square-wave signals, female by system Line open delta, ground connection become the zero sequence loop of neutral point or capacitor bank neutral point injected system, and signal acquiring system is adopted With high-performance A/D sampling circuits and Digital Signal Processing, the signal to injecting carries out calculating analysis, so as to obtain system capacitance electricity The size of stream.
Different injection methods is illustrated by three embodiments separately below.
Embodiment 1
See Fig. 2, a kind of low current neutral grounding electric network capacitance current measurement method is surveyed using bus open delta PT injection methods Amount, including:HC-1 types Capacitive current tester, band fuse insulating bar, grounding transformer, arc suppression coil and busbar transformer, its Median generatrix step down side delta connection, arc suppression coil is exited, and HC-1 types Capacitive current tester is to supporting special of instrument The constant current square-wave signal of 5Hz is injected with PT low-pressure sides, red clip is connect into a ends black clip and is connect x ends in special PT low-pressure sides shape Into loop, and grounding transformer neutral point is snapped into by the insulating bar with fuse in PT high-pressure sides and is formed with line mutual-ground capacitor Loop, by carrying out Fourier space decomposition and PT low-pressure side voltages supporting to instrument and electric current survey to the square-wave signal being input into Amount, calculates the ground capacitance of circuit, and then obtain capacitance current.
See Fig. 3, a kind of low current neutral grounding electric network capacitance current measurement method is surveyed using grounding transformer neutral point injection method Amount, in the neutral point injected signal of compensation capacitor group, selection capacitor bank neutral point injection way is measured, and it is mainly wrapped Include:HC-1 types Capacitive current tester, band fuse insulating bar, compensation capacitor group, arc suppression coil and busbar transformer, wherein female Line transformer low-pressure side delta connection, arc suppression coil is exited.HC-1 types Capacitive current tester red clip is connect into a ends black Clip connects x ends and forms loop in special PT low-pressure sides, and snaps into capacitor bank by the insulating bar with fuse in PT high-pressure sides Neutral point forms loop with line mutual-ground capacitor, and Fourier space decomposition is carried out and to instrument by the square-wave signal being input into Supporting PT low-pressure side voltages and current measurement, calculate the ground capacitance of circuit, then subtract compensating electric capacity according to reduction formula Amount, obtains real capacitance, and then obtain capacitance current.
See Fig. 4, a kind of low current neutral grounding electric network capacitance current measurement method, surveyed using grounding transformer neutral point injection method Amount wiring, in busbar transformer open delta Injection Signal, including:HC-1 types Capacitive current tester, band fuse insulating bar, benefit Capacitor bank, arc suppression coil and busbar transformer, wherein busbar transformer low-pressure side delta connection are repaid, secondary resonance elimination device breaks Open, high resistant resonance eliminator short circuit.HC-1 types Capacitive current tester red clip is connect into L ends black clip, and to connect N-terminal low in special PT Pressure side forms loop, and Fourier space decomposition and PT low-pressure side voltages supporting to instrument are carried out by the square-wave signal being input into And current measurement, the ground capacitance of circuit is calculated, and then obtain capacitance current.
Although disclosing embodiments of the invention and accompanying drawing for the purpose of illustration, those skilled in the art can manage Solution:Do not depart from the present invention and spirit and scope of the appended claims in, various replacements, change and modifications all be it is possible, Therefore, the scope of the present invention is not limited to embodiment and accompanying drawing disclosure of that.

Claims (8)

1. a kind of low current neutral grounding electric network capacitance current measurement method, including HC-1 types Capacitive current tester and measurement apparatus, It is characterized in that:HC-1 types Capacitive current tester injects 5Hz constant current square-wave signals to power distribution network zero sequence loop, to line-to-ground Electric capacity carries out discharge and recharge, and so as to be measured to power distribution network ground capacity electric current, measurement apparatus are by AC and DC power-supply system, number Word signal microprocessor, signal gathering unit and power electronic circuit.capacitor composition, digital signal microprocessor control electric power electricity Sub- inverter circuit produces a constant current 5Hz square-wave signals, and neutral point or capacitor are become by system busbar open delta, ground connection The zero sequence loop of group neutral point injected system, signal acquiring system uses high-performance A/D sampling circuits and Digital Signal Processing.
2. low current neutral grounding electric network capacitance current measurement method according to claim 1, it is characterised in that:The HC-1 types Capacitive current tester is connected to bis- open deltas of system under test (SUT) bus PT by Special cable wire.
3. low current neutral grounding electric network capacitance current measurement method according to claim 1, it is characterised in that:The HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then by insulating bar by the supporting PT of instrument once Side is connected to grounding transformer neutral point.
4. low current neutral grounding electric network capacitance current measurement method according to claim 1, it is characterised in that:It is described HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then by insulating bar that instrument is supporting PT primary sides connect a compensation capacitor group.
5. low current neutral grounding electric network capacitance current measurement method according to claim 1, it is characterised in that:In PT low-pressure sides Injection constant current i0, then have electric current i in PT high-pressure sides1, i2, i3, PT exciting currents ia, ib, icIf, PT high-low pressure umber of turns Respectively n1, n2Then there is following relation:
n1(i1-ia)=n2i0
n1(i2-ib)=n2i0
n1(i3-ic)=n2i0,
After Injection Signal is for the constant current square-wave signal of 5Hz, the signal to injecting carries out Fourier transformation and signal analysis.For The square-wave signal of injection by the deployable sine wave sum different into angular frequency of fourier series, i.e.,:
u ( t ) = 2 U m π ( sinω 5 t + 1 3 sinω 15 t + 1 5 sinω 25 t + ... )
Sampling is carried out in voltage transformer secondary open delta and data processing respectively obtains U5, U15, U25And I5, I15, I25Then have:
U 5 = I 5 R 2 + ( ω 5 L - 1 ω 5 C ) 2
U 15 = I 15 R 2 + ( ω 15 L - 1 ω 15 C ) 2
U 25 = I 25 R 2 + ( ω 25 L - 1 ω 25 C ) 2
Signal to injecting carries out calculating analysis, so as to obtain the size of system capacitive current.
6. low current neutral grounding electric network capacitance current measurement method according to claim 2, it is characterised in that:The HC-1 types Capacitive current tester is connected in bis- circuits of open delta of system under test (SUT) bus PT by Special cable wire, including:HC- 1 type Capacitive current tester, band fuse insulating bar, grounding transformer, arc suppression coil and busbar transformer, wherein busbar transformer Low-pressure side delta connection, arc suppression coil is exited, and HC-1 types Capacitive current tester is noted to the supporting special PT low-pressure sides of instrument Enter the constant current square-wave signal of 5Hz, red clip is connect into a ends black clip connects x ends in special PT low-pressure sides formation loop, and in PT High-pressure side snaps into grounding transformer neutral point and forms loop with line mutual-ground capacitor by the insulating bar with fuse, by defeated The square-wave signal for entering carries out Fourier space decomposition and PT low-pressure side voltages supporting to instrument and current measurement, calculates circuit Ground capacitance, and then obtain capacitance current.
7. low current neutral grounding electric network capacitance current measurement method according to claim 3, it is characterised in that:The HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then by insulating bar by the supporting PT of instrument once Side is connected in the circuit of grounding transformer neutral point, including:HC-1 types Capacitive current tester, band fuse insulating bar, compensation Capacitor bank, arc suppression coil and busbar transformer, wherein busbar transformer low-pressure side delta connection, arc suppression coil are exited.Will HC-1 types Capacitive current tester red clip connects a ends black clip and connects x ends and forms loop in special PT low-pressure sides, and high in PT Pressure side snaps into capacitor bank neutral point and forms loop with line mutual-ground capacitor by the insulating bar with fuse, by input Square-wave signal carries out Fourier space decomposition and PT low-pressure side voltages supporting to instrument and current measurement, calculates circuit over the ground Capacitance, then subtracts compensating electric capacity amount according to reduction formula, obtains real capacitance, and then obtain capacitance current.
8. low current neutral grounding electric network capacitance current measurement method according to claim 4, it is characterised in that:It is described HC-1 types Capacitive current tester is connected to the secondary side of the supporting PT of instrument by private cable, then by insulating bar that instrument is supporting PT primary sides are connected in the circuit of a compensation capacitor group, including:HC-1 types Capacitive current tester, band fuse insulating bar, benefit Capacitor bank, arc suppression coil and busbar transformer, wherein busbar transformer low-pressure side delta connection are repaid, secondary resonance elimination device breaks Open, high resistant resonance eliminator short circuit.HC-1 types Capacitive current tester red clip is connect into L ends black clip, and to connect N-terminal low in special PT Pressure side forms loop, and Fourier space decomposition and PT low-pressure side voltages supporting to instrument are carried out by the square-wave signal being input into And current measurement, the ground capacitance of circuit is calculated, and then obtain capacitance current.
CN201611264176.3A 2016-12-30 2016-12-30 A kind of low current neutral grounding electric network capacitance current measurement method Pending CN106771647A (en)

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CN108872783A (en) * 2018-05-24 2018-11-23 国网浙江省电力有限公司电力科学研究院 Resonant earthed system singlephase earth fault Section Location
CN109782055A (en) * 2019-04-02 2019-05-21 云南电网有限责任公司电力科学研究院 A kind of isolated neutral system capacitance current measurement method and device
CN109901019A (en) * 2019-04-02 2019-06-18 云南电网有限责任公司电力科学研究院 A kind of resonant earthed system capacitance current measurement method and device
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CN107390032A (en) * 2017-07-06 2017-11-24 重庆大学 Line mutual-ground capacitor parameter measurement system and measuring method
CN108872783A (en) * 2018-05-24 2018-11-23 国网浙江省电力有限公司电力科学研究院 Resonant earthed system singlephase earth fault Section Location
CN108872783B (en) * 2018-05-24 2020-10-09 国网浙江省电力有限公司电力科学研究院 Single-phase earth fault section positioning method of resonance earthing system
CN108828316A (en) * 2018-06-26 2018-11-16 国网山东省电力公司泰安供电公司 Line parameter circuit value measurement method, device and electronic equipment
CN109782055A (en) * 2019-04-02 2019-05-21 云南电网有限责任公司电力科学研究院 A kind of isolated neutral system capacitance current measurement method and device
CN109901019A (en) * 2019-04-02 2019-06-18 云南电网有限责任公司电力科学研究院 A kind of resonant earthed system capacitance current measurement method and device
CN112067878A (en) * 2020-09-02 2020-12-11 邯郸市科维电气有限公司 Capacitance current on-line measuring method and device for secondary side bias capacitor of grounding transformer
CN112505397A (en) * 2020-11-10 2021-03-16 国网河南省电力公司郑州供电公司 10kV bus capacitance current monitoring method

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