CN2629312Y - 3-35KV antiresonance voltage limiting arc suppression coil - Google Patents

Abstract

The utility model relates to a neutral point earthing device of power system. A 3-3.5V anti-tuning and voltage limiting non-arc coil is composed of multi-thread neutral point inductanting coil L<H> component and a compound impedance Z<F> in series. The utility model is characterized in that the compound impedance Z<F> component is composed of a series component of the sensor component L<P> connecting with a nonlinear inductance *<m> and a resistance Rm in series, and as well as a parallel connection component of a nonlinear inductance *<F> and a capacitor C<F>. The voltage limiting non-arc coil is grounded to 6-35KV power system to educe the neutral point or indirectly educe the neutral point. The L<H> component provides an adjustable compensate current I <H>; the Z<F> component provides the compensation current I<F>; the gross compensate current I<K> is totaled by I<H> and I<F>. The ratio of I<H> and I<F> can be adjusted in the range of 1-25 class by class. The utility model can avoid tuning resonance reliably, and allows to be operated under the conditions of lack of compensate, full compensate, over-compensate and any other compensate, and meanwhile can limit the largest arc earthing transient oscillation over-voltage less than 2.5 times as much as the phase voltage value.

Description

3～35KV antiresonance voltage limiting arc suppression coil

Technical field

The utility model relates to a kind of neutral point of electric network grounding apparatus, is in particular a kind of antiresonance voltage limiting arc suppression coil that is used for 3～35KV electrical network.

Background technology

3～35KV electrical network adopts the neutral by arc extinction coil grounding operation, has compensation, extinguishing arc and anti-ferro resonance function.The arc suppression coil of Cai Yonging is the single neutral point inductance coil of many parted hairs that band air-gap iron core coiling is made for a long time, and this extinguisher is called traditional arc suppression coil.The application of tradition arc suppression coil has two drawbacks.The one,, because of there not being anti-resonance tuning ability, must adjust and under overcompensation, move, but overcompensation again should be not excessive, thereby adjust difficulty, can not satisfy service requirement.The 2nd,, " beat frequency " vibration overvoltage that can produce 3.0 times of phase voltage amplitudes in service is with the arc grounding transient oscillation overvoltage of 4.0 times of the mutually electric amplitudes that causes thus.Recent two decades comes, the automatic tuning arc depression coil by microcomputerized controller enforcement control of 6～10KV electrical network installing, move though can adjust in full compensation automatically or be bordering under the full compensation, has the good compensation effect, but anti-resonance tuning exists and is interrupted drawback intermittently, during intermittent single-phase arc grounding takes place, can produce and be analogous to the identical serious overvoltage that traditional arc suppression coil is used.The serious overvoltage that produces not necessarily makes insulation against ground damage immediately to cause accident, but causes the insulation against ground damage accumulation, will reduce the interior over a long time safety operation level of electrical network.

The utility model content

The purpose of this utility model is to provide a kind of drawback that can overcome above-mentioned traditional arc suppression coil and automatic tuning arc depression coil, not only have good compensation, extinguishing arc and anti-ferro resonance function, have 3～35KV antiresonance voltage limiting arc suppression coil of anti-harmonious pressure limiting performance simultaneously again.

The anti-humorous performance that has can guarantee uninterruptedly to avoid continuously resonance tuning, thereby allows to move under undercompensation, full compensation, any compensation situation of overcompensation.The pressure limiting performance that has can be with the pressure limiting of " beat frequency " oscillating voltage to being no more than phase voltage amplitude 10% and can be with the pressure limiting of arc grounding transient oscillation overvoltage to being no more than 2.5 times of phase voltage amplitude.

To achieve these goals, the technical solution of the utility model is: 3～35KV antiresonance voltage limiting arc suppression coil, and by many parted hairs neutral point inductance coil L _HParts and neutral point mix impedance Z _FThe parts composition that is connected in parallel.Mix impedance Z _FParts are by inductance component L _PNonlinear inductance is connected in parallel

Resistance R m series element is again with nonlinear inductance

Capacitor C _FThe element in parallel formation that is in series.

Nonlinear inductance Wind with coil by no air gap cold-reduced silicon sheet iron core and to make R _mBe the thread resistance of resistance wire, C _FBe electric capacity.During the electrical network single-phase earthing, L _HParts provide the adjustable compensation electric current I _H, Z _FThe parts electric current I that affords redress _F, total offset current I _KBe I _HWith I _FSum.I _HWith I _FRatio, can adjust at 0～25 scope internal classification.

To the utility model voltage-current characteristic and anti-humorous, pressure limiting performance, explanation performs an analysis respectively below.

One, rated voltage of the present utility model is U _H, U _HEqual to use 1.05 times of the specified phase voltage of electrical network.L _HThe volt of parts---the peace characteristic is: effect voltage is at 0～1.10U _HIn the gamut, be bordering on linearity.Z _FThe volt of parts---the peace characteristic is: effect voltage is at 0～0.05U _HIn the scope, Z _FImpedance is rendered as and is bordering on constant power frequency capacitive reactances; Effect voltage is at 0.05～0.40U _HIn the scope, Z _FImpedance is rendered as nonlinear impedance; Effect voltage is at 0.40～1.10U _HIn the scope, Z _FVolt---the peace characteristic be bordering on linearity.

Two, electrical network does not have under the earth fault, the capacitive reactance X of three-phase ground capacitance ∑ C _{∑ C}, with the arc suppression coil inductance L _KInduction reactance X _KConstitute the shunt circuit, because physical presence neutral point of electric network asymmetrical voltage U in this loop _O, thereby can constitute resonance tuning.When constituting complete resonance tuning, because of X _{∑ C}Equal X _K, electric current only is subjected to the arc suppression coil resistance R in the loop _KRestriction, thereby can produce serious neutral point power-frequency overvoltage over the ground.Under the normal operation of electrical network, neutral point voltage to earth U _OKValue does not allow to surpass 0.15U _HTraditional arc suppression coil as a maximum offset current 30A runs on the 35KV electrical network, and I adjusts _KBe 30A, operation phase voltage U _φEqual U _H, for $35\&times;1.05/\sqrt{3}\mathrm{KV},$ Equal 21218 volts, R _KValue is 12 Europe, when constituting complete resonance tuning, for making U _OKValue is not more than 0.15U _HThe maximum U that allows _OValue only is 54 volts.The U of actual 35KV electrical network _OMagnitude of voltage, normal maximum can reach about 640 volts.Therefore, must adjust, guarantee that when electric network capacitance and current reduces unlikely formation compensates resonance tuning entirely in overcompensation operation down.Adopt the utility model, work as Z _FVoltage is not more than 0.05U on the parts _H, Z _FImpedance is rendered as the power frequency capacitive reactances, passes through Z _FThe maximum permissible current I of impedance _FC, it is U that the maximum of foundation allows the neutral point asymmetrical voltage _OFU when electrical network _OMagnitude of voltage is no more than U _OFValue just can make U _OKMagnitude of voltage is no more than 0.05U _H, less than maximum permissible value 0.15U _H, can guarantee to avoid uninterruptedly resonance tuning.The design example that the utility model is used for the 35KV electrical network is FJL---30A/35 type antiresonance voltage limiting arc suppression coil U _HValue is 21218V, I _KBe 4A, 10A, 20A and 30A, be total to fourth gear, L _HParts are provided with 6A, 16A, three branch head currents of 26A, Z _FThe I of parts _FValue is 4.0A.Anti-tuning its ability of shaking of FJL---30A/35 type is designed to Z _FVoltage is not more than 0.05U on the parts _HPass through Z down, _FMaximum permissible current I _FCValue is taken as 1.20A.Work as I _KValue is adjusted and is 10A, the unbalanced earth fault capacitance current I of 35KA electrical network _{∑ C}Value calculates U for 12A _OFValue is 0.12U _H, equal 2546 volts, much larger than the normal maximum U of electrical network _O640 volts of magnitudes of voltage.Even serious disconnection fault takes place, do not cause the U of electrical network yet _OMagnitude of voltage is above 2546 volts.Work as I _KBe 30A, I _{∑ C}Be 34A, calculate U _OFValue is 0.047U _H, equal 997 volts, also greater than the normal maximum U of electrical network _O640 volts.In fact, as the I of 35KV electrical network _{∑ C}Value reaches 34A, and electrical network is connected with cable, the normal maximum U of electrical network _OVoltage is unlikely to surpass 400 volts, and serious disconnection fault takes place, and does not also cause the U of electrical network _OVoltage is above 997 volts.If the disconnection fault of especially severe takes place, make the U of electrical network _OMagnitude of voltage surpasses U _OFMagnitude of voltage, this is Z _FVoltage will be above 0.05U on the parts _H, Z _FImpedance is emotional resistance by being rendered as rapid change of power frequency capacitive reactances, will cause serious resonance tuning, Z _FVoltage rises rapidly on the parts, makes

The iron core of nonlinear inductance takes place seriously saturated, produces about 0.4U _HSerious saturation voltage.This serious saturation voltage will make resonance tuning be restricted, and make U _OKVoltage magnitude is unlikely to be surpassed $0.73\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ Arbitrary amplitude of maximum voltage relatively is no more than on the electrical network $1.73\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ Allow continuous service 2 hours, electrical network is not had harm.Electrical network generation single-phase earthing, after ground arc extinguished, the free oscillation evanescent voltage of generation also made Z _FThe super 0.05U of voltage on the parts _HThe DC voltage component of free oscillation evanescent voltage makes but at this moment,

Iron core all take place seriously saturatedly, make resistance R _mCan play a role.Choose best R _mResistance value can not only reliably be avoided resonance tuning, and free oscillation voltage is decayed rapidly, when ground arc extinguishes back 15～35ms, with Z _FLast voltage magnitude is reduced to $0.05\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ Below the value, recover normal anti-resonance tuning heavily again.

Three, 3～35KV arc suppression coil earthing electric network behind the single-phase stable grounding arc extinction, produces free oscillation evanescent voltage U _{∑ C}, initial amplitude is

When fault phase-to-ground voltage value is

The time, single-phase arc grounding takes place, produce perfecting on the two-phase $2.3\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ Arc grounding transient oscillation overvoltage, extinguish arcs when in the transient oscillation maximum peak voltage, the free oscillation evanescent voltage of generation is U ' _{∑ C}Voltage, U ' _{∑ C}The initial amplitude of voltage is $1.53\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}.$ U _{∑ C}Voltage or U ' _{∑ C}Voltage is all by e ^-kRtDecay, K _RBe attenuation coefficient.K _REqual R _K/ 2L _K, L _KBe the inductance of arc suppression coil equipment, R _KFor with L _KThe substitutional resistance of series connection.As traditional arc suppression coil of a maximum offset current 30A of 35KV electrical network installing, I _KBe 30A, work as I _{∑ C}Value is overcompensation 11.1% for 27A.At this moment, U _HValue is 21218 volts, L _KBe 2.25 henries, R _KBe 12 Europe, K _RValue is 2.70, overcompensation 11.1% time, U _{∑ C}The voltage oscillation frequency is 52.7 cycle per seconds.For U ' _{∑ C}Voltage is because of the starting voltage amplitude is $1.53\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ Make L _KIron core take place saturated, L _KValue descends, the U ' under the overcompensation 11.1% _{∑ C}The initial frequency of oscillation of voltage rises to about 61 cycle per seconds, initial K _RValue increases to about 3.7.Moment after ground arc extinguishes, U _{∑ C}Voltage or U ' _{∑ C}The initial, peak of voltage and fault supply voltage peak value mutually are reversed polarity, extinguish arc after, U _{∑ C}Voltage or U ' _{∑ C}Voltage and fault are mutually, non-fault phase power frequency 50 cycle per second supply voltages all constitute " beat frequency " vibration, make three relatively all to produce " beat frequency " vibration overvoltage.For U _{∑ C}When voltage, ground arc extinguished back 180ms, " beat frequency " vibration overvoltage that the fault point is produced over the ground was $1.60\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}.$ For U _{∑ C}Voltage, after ground arc extinguishes, only through about 70ms, just make " beat frequency " vibration overvoltage that the fault point produces over the ground up to $2.21\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}.$ When this $2.21\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ Overvoltage causes the more weak over the ground insulation breakdown in fault point, take place to repeat arc grounding, perfecting the arc grounding transient oscillation overvoltage that produces on the two-phase is $3.30\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ Extinguish arcs when in the transient oscillation maximum peak voltage, on three-phase ground capacitance ∑ C, set up immediately initial voltage magnitude up to $2.20\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ Free oscillation evanescent voltage U " _ECU " _ECVoltage makes L _KIron core take place seriously saturated, L _KValue significantly descends, U " _{∑ C}The initial frequency of oscillation of voltage rises to about 79 cycle per seconds, at this moment, and decay coefficient K _RValue increases about three times, but because U " _{∑ C}The frequency of oscillation of voltage is higher, behind the arc extinction, and through 6.6ms, U " _{∑ C}Voltage magnitude decays to $2.05\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ With lag behind fault mutually 120 ° of power frequency electrical angles perfect the phase supply voltage, formation is bordering on same polarity and superposes with peak value, make this " beat frequency " vibration overvoltage relatively 3.0 times up to the phase voltage amplitude, when this overvoltage causes arc grounding, the arc grounding transient oscillation overvoltage of 4.0 times of phase voltage amplitudes will be produced.When adopting self-tuning arc-extinguishing equipment, on the electrical network overhead wire intermittent arc grounding takes place, behind each quiet earth arc extinction, take over control outside during resonance tuning resistance about 50ms that series connection does not insert as yet, the maximum power-frequency overvoltage that produces on the electrical network can reach 2.1～2.7 times, when this power-frequency overvoltage causes arc grounding, also can produce to be analogous to the identical serious overvoltage that traditional arc suppression coil is used.Adopt the utility model---antiresonance voltage limiting arc suppression coil, behind each single-phase earthing arc extinction, U can decay rapidly _{∑ C}Voltage or U ' _{∑ C}Voltage is to very little, make the fault point over the ground " beat frequency " oscillating voltage be no more than phase voltage amplitude 10%, thereby can be with the pressure limiting of arc grounding transient oscillation overvoltage to being no more than 2.5 times of phase voltage amplitude.U decays rapidly _{∑ C}Voltage or U ' _{∑ C}The mechanism of voltage is: behind the single-phase earthing arc extinction, and the U of generation _{∑ C}Voltage or U ' _{∑ C}The DC voltage component of voltage makes With

The iron core wink of nonlinear inductance promptly enters serious saturated situation, makes resistance R _mPlay a role, can be rapidly with U _{∑ C}Voltage or U ' _{∑ C}Voltage attenuation is to very little. select best R _mResistance value makes at R _mThe loss that produces on the resistance can be extinguished the capacitance energy storage that the back promptly preserves in wink by very fast consumption ground arc on three-phase ground capacitance ∑ C, thereby can be when ground arc extinguishes back 15～35ms, with U _{∑ C}Voltage or U ' _{∑ C}Voltage attenuation makes fault point " beat frequency " oscillating voltage over the ground be no more than phase voltage amplitude 10% to very little.

Description of drawings

The wiring sketch that Fig. 1 the utility model directly inserts

Fig. 2 is that power supply does not have the equivalent analysis chart of ground connection Fig. 1

Fig. 3 is single-phase earthing compensation image 1 an equivalent analysis chart

The wiring sketch that Fig. 4 the utility model inserts indirectly

Embodiment

The antiresonance voltage limiting arc suppression coil is by many parted hairs neutral point inductance coil L _HParts and neutral point mix impedance Z _FThe parts composition that is connected in parallel.Mix impedance Z _FParts are by inductance component L _PNonlinear inductance is connected in parallel Resistance R m series element is again with nonlinear inductance Capacitor C _FThe element in parallel formation that is in series.

For further the utility model being done more specifically explanation, with reference to the accompanying drawings the embodiment of enumerating is done computational analysis.

Among Fig. 1, for 3～35KV electrical network of drawing property point " 0 " is arranged, " H " of the present utility model end is with " the P end is connected, and directly inserts " 0 " " 1 "." 4 " are L among Fig. 1 _HParts, " 5 " are Z _FParts, two parts earth terminal " m " common grounds.

Among Fig. 2, U _OBe neutral point of electric network asymmetrical voltage, X _LHBe L _HParts operation induction reactance separately, R _HBe L _HCoil resistance; X _LPBe L _PThe induction reactance of inductance element, R _PBe L _PCoil resistance; R _mFor with

The high value resistor of nonlinear inductance series connection; R _FFor

Non-linear inductor resistance; C _FFor capacitance is C _FHigh-voltage capacitor.

Among Fig. 3, get operation phase voltage U _φEqual U _H, I _{∑ C}Be unbalanced earth fault capacitance current, I _KBe offset current, I _KEqual I _HWith I _FSum, I _mBe the earth fault aftercurrent.

Among Fig. 4, " 2 " for there not being 3～35KV electrical network of drawing neutral point, " 3 " are grounding transformer T ₀, by T ₀Draw artificial neutral point " 0 ", insert the utility model again.The equivalent analysis chart that is similar to Fig. 2, Fig. 3 of Fig. 4 needs after " H " " P " connection among the figure, and serial connection is gone into T ₀1/3 zero sequence impedance, insert neutral point " 0 " again.

The embodiment FJL-30A/35 type antiresonance voltage limiting arc suppression coil of enumerating in above-mentioned that is used for the 35KV electrical network, wiring sketch such as Fig. 1, electrical network normally do not have equivalent analysis chart such as Fig. 2 of ground connection.U _HBe 2128 volts, parameter is X among Fig. 2 _LPBe 3457 Europe, R _pBe 50 Europe, R _FBe 40 Europe, C _FBe 0.78 microfarad, R _mValue is 1200 Europe.As the I that adjusts _KBe 10A, I among Fig. 2 _HBe 6A, I _FBe 4A, X _LHBe 3536 Europe, R _HBe 42 Europe; As the I that adjusts _KBe 30A, I among Fig. 2 _HBe 26A, I _FBe 4A, X _LHBe 816 Europe, R _HBe 14 Europe.Among Fig. 2 between " 0 " and " m " voltage be not more than 0.05U _H, the maximum I that allows _FValue is I _FC, I _FCBe designed to 1.2A.Work as I _KBe 10A, I _{∑ C}Be 12A, X _{∑ C}Be 1768 Europe, calculate the maximum neutral point asymmetrical voltage U that allows by Fig. 2 _OFBe 0.12U _HWork as I _KBe 30A, I _{∑ C}Be 34A, X _{∑ C}Be 624 Europe, calculate at this moment U by Fig. 2 _OFValue is 0.047U _HBecause of R among Fig. 2 _mValue is taken as 1200 Europe, the U that produces behind the electrical network single-phase earthing arc extinction _{∑ C}Voltage or U ' _{∑ C}Voltage is all by e ^-KFTVery fast decay, K _FBe attenuation coefficient.K _FValue is much higher than the decay coefficient K when adopting traditional arc suppression coil _RValue.Calculate I _KBe 10A, U _{∑ C}Be 12A, U _{∑ C}Voltage or U ' _{∑ C}The frequency of oscillation of voltage was 106 seconds in week, K _FValue is up to 362, when ground arc extinguishes back 10ms, $1.53\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ The U ' of starting voltage amplitude _{∑ C}The amplitude of voltage decays to $0.041\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ The maximum that produces over the ground in the fault point " beat frequency " oscillating voltage amplitude is no more than 3.3% of phase voltage amplitude.Work as I _KBe 30A, I _{∑ C}Be 34A, ground arc extinguishes the U that the back produces _{∑ C}Voltage or U ' _{∑ C}The frequency of oscillation of voltage is 62 cycle per seconds, K _FValue is 103, when ground arc extinguishes back 35ms, and initial U ' _{∑ C}Voltage magnitude is $1.53\&times;\sqrt{2}{U}_{\mathrm{\&phi;}}$ Voltage magnitude decay to $0.042\&times;\sqrt{2}{U}_{\mathrm{\&phi;}},$ The maximum that produces over the ground in the fault point " beat frequency " oscillating voltage is no more than phase voltage amplitude 2.3%.

FJL-30A/35 type antiresonance voltage limiting arc suppression coil of 35KV electrical network installing, isopleth map such as Fig. 3 are analyzed in the compensation of electrical network single-phase earthing.During the electrical network single-phase earthing, Iron core be in unsaturated situation, so do not count among Fig. 3 Branch road is to the very little influence of ground compensation.As Fig. 3, during the electrical network single-phase earthing,

Iron core be in the saturated situation of the degree of depth,

Voltage is designed to 7390 volts, L on the element in parallel _PVoltage is designed to 13828 volts on the inductance element.During the electrical network single-phase earthing, because

Iron core be in the saturated situation of the degree of depth, produce third harmonic voltage, make Z _FParts provide about 0.4A amplitude triple harmonic current to earth fault.But this triple harmonic current amplitude is still little, and is very little to the adverse effect of pressing the generation of earth fault point arc extinction.

3～35KV electrical network installing the utility model antiresonance voltage limiting arc suppression coil, under any compensation situation, can be promptly after all avoiding resonance tuning and each ground arc to extinguish fully with fault point " beat frequency " oscillating voltage pressure limiting over the ground to being no more than phase voltage amplitude 10%.Under the capacitance current change conditions of most electrical networks, use the utility model, offset current is adjusted is capacitance current change mean value, can obtain to be equal to the same compensation of automatic tuning, extinguishing arc effect.Therefore, but when using the utility model round Realization good compensation, extinguishing arc, anti-ferro resonance and significantly reducing overvoltage level, also can realize the simple and operational reliability height of operation maintenance.

Claims (2)

1,3～35KV antiresonance voltage limiting arc suppression coil is by many parted hairs neutral point inductance coil L _HParts and mixing impedance Z _FThe parts composition that is connected in parallel is characterized in that mixing impedance Z _FParts are by inductance component L _PNonlinear inductance is connected in parallel

Resistance R m series element is again with nonlinear inductance Capacitor C _FThe element in parallel formation that is in series.

2,3～35KV antiresonance voltage limiting arc suppression coil according to claim 1 is characterized in that nonlinear inductance

Nonlinear inductance All, wind with coil and make for make no air-gap iron core by cold-reduced silicon sheet.

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