CN203251090U - Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil - Google Patents
Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil Download PDFInfo
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- CN203251090U CN203251090U CN 201220736176 CN201220736176U CN203251090U CN 203251090 U CN203251090 U CN 203251090U CN 201220736176 CN201220736176 CN 201220736176 CN 201220736176 U CN201220736176 U CN 201220736176U CN 203251090 U CN203251090 U CN 203251090U
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- 238000004804 winding Methods 0.000 claims description 23
- 230000000087 stabilizing effect Effects 0.000 claims description 15
- 239000004568 cement Substances 0.000 claims description 9
- 239000003990 capacitor Substances 0.000 claims description 6
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- 238000009413 insulation Methods 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 1
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- 238000010891 electric arc Methods 0.000 description 1
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Abstract
The invention relates to a novel turn-adjustable switching device for a secondary damping resistor of an arc suppression coil. The device comprises a rectifying circuit, a resistor voltage dividing circuit, a voltage comparison circuit, a relay contact interlocking control circuit, a relay drive circuit and a line selecting interface circuit. The rectifying circuit is used for alternating-current and direct-current conversion so as to provide a working power supply for the circuits; the resistor voltage dividing circuit is mainly used for limiting currents and dividing voltages; the voltage comparison circuit is used for damping switching during different voltage thresholds; the relay contact interlocking control circuit is used for achieving a dual-protection function, alarming when a first group of failures occur and providing a backup protection function; the relay drive circuit is mainly used for controlling a relay coil by comparing output voltages; and the line selecting interface circuit mainly passes through the relay drive circuit and is independent of the voltage comparison circuit and used for achieving a resistor switching function according to signals given out by a line selecting device. The device is simple and reliable in circuits, directly acquires a voltage across the damping resistor and enters a voltage detection circuit after passing through the voltage dividing circuit, so that cost is saved.
Description
Technical field
The utility model relates to a kind of arc suppression coil damped resistor control device, especially a kind of Quadratic Damping resistance switching control device based on turn-adjusting arc-extinguishing winding.
Background technology
Along with the development of China's economic construction, the power system transmission line capacitive earth current shows a rising trend, in case single-phase earthing occurs, the larger earth current that meeting is flow through at earth point, healthy phases voltage raises simultaneously, also can destroy insulation, in the most serious situation two phase ground short circuit can occur.
For improving power supply reliability; clear among the power industry standard DL/T 620-1997 " overvoltage protection of alternating-current electric device and insulation coordination ": the system that 3～10kV overhead transmission line consists of and all 35kV, 66kV electrical network; when single-phase earth fault current during greater than 10A; neutral point should be installed the arc suppression coil neutral point of electric network need adopt the grounding through arc mode; its main purpose is to reduce ground connection residual flow Id; from going out, improve power supply reliability in order to electric arc.When power system operating mode changed, corresponding adjusting was done in the arc suppression coil tap.
Regulate arc suppression coil electric current I L and must take into account two aspect factors: one makes ground connection residual flow Id minimum; Its two, can not make neutral point of electric network displacement voltage UN too high when normally moving, UN＜15% phase voltage UX.But these two kinds of factors are mutually restrictions.That is: Id minimum, then require arc suppression coil to be adjusted at full compensation IL=Ic or near full compensating coefficient, be i.e. off resonance degree υ=(IL-Ic)/Ic=0.At this moment, under the asymmetrical voltage effect, arc suppression coil reactance and power-to-ground capacitance are the series resonance state, only rely on the R in the natural damping, and UN is inevitable very high.At damping resistance of arc suppression coil loop series connection, the contradiction of Id and UN is coordinated preferably.Therefore, at present the presetting system produced of China is regulated arc suppression coil device automatically, linear damping resistance of series connection in the grounding through arc loop mostly, and on the side controllable silicon in parallel.When electrical network normally moved, switch disconnected, and dropped into damping resistance, because the existence of damping resistance, the ratio of damping of resonant tank increases a lot, UN is controlled in the scope of permissible value; When electrical network ground connection, switch closure, short circuit resistance can make the abundant compensation of ground capacitance current of arc suppression coil electric current I L, makes the ground connection residual flow very little.Tradition damping resistance protective device is because the existence of Power supply so that damping resistance case inner high voltage part and low-pressure section are not accomplished isolation, can not in time be moved in case protect, and the high pressure string will lead to larger accident to mains side.
In view of this, be necessary to provide a kind of novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, to satisfy the commercial Application needs.
Summary of the invention
The purpose of this utility model is: in order to overcome above-mentioned problems of the prior art, thereby provide a kind of damp resistance throw-cut device, overcome the manually operated inherent defect of damping resistance parallel connection short circuit device in the Automatic-track arc eliminating device, neutral point displacement voltage is in the permissible value.When electrical network normally moved, damping dropped into, because the existence of damping resistance, the ratio of damping of resonant tank increases a lot, though this moment arc suppression coil and system be in resonance condition, still neutral point displacement voltage can be controlled in the scope of permissible value; When electrical network ground connection, the damping resistance excision can make the abundant compensation of ground capacitance current of arc suppression coil electric current, makes the ground connection residual flow very little.
The technical solution of the utility model is: a kind of novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, it is characterized in that, formed by rectification circuit, resistor voltage divider circuit, voltage comparator circuit, relay contact interlocking control circuit, relay drive circuit, route selection interface circuit, the signal of rectification circuit exports voltage comparator circuit and relay contact interlocking control circuit to, realize AC-DC conversion, circuit work power is provided; The signal of resistor voltage divider circuit exports voltage comparator circuit and relay contact interlocking control circuit to, realizes current limliting and dividing potential drop; Voltage comparator circuit is electrically connected with the damping circuit contactor coil, the damping switching when realizing different voltage threshold; The relay contact interlocking control circuit exports the fault alarm module to, realizes double protection functions, provides warning when first group of fault, and the backup protection function is provided; The signal of relay drive circuit exports the relay contact interlocking control circuit to, realizes by comparing the output voltage realization to the control of relay coil; The route selection interface circuit is electrically connected with voltage comparator circuit and relay contact interlocking control circuit, by relay drive circuit is provided, and is independent of voltage comparator circuit, realizes resistance switching function according to the signal that line selection apparatus provides.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device; it is characterized in that: rectification circuit adopts rectification chip KBP202; alternating voltage Uro is become DC power supply; voltage stabilizing and the power voltage stabilizing didoe by dc capacitor and 24V carry out voltage stabilizing; wherein voltage stabilizing didoe is to shield; dc capacitor plays voltage stabilizing and flat ripple effect, and the power supply behind the rectifying and voltage-stabilizing provides the working power of chip and relay drive circuit.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, it is characterized in that: resistor voltage divider circuit is comprised of cement resistor R1, R2, R3, this cement resistor is all chosen high-power resistance, can pass through for a long time the 50mA electric current, by cement resistor damping resistance two ends output voltage U ro be carried out current limliting and dividing potential drop.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, it is characterized in that: voltage comparator circuit and relay contact interlocking control circuit carry out dividing potential drop by resistance R 2, R3, R4 to the 24V direct current, obtain two magnitudes of voltage that voltage is different, this value is the threshold voltage value of comparator; The R4 of access comparator in-phase end is adjustable resistance, and adjusting R4 is the threshold value range of capable of regulating comparator; Wherein the normally-closed contact of a group relay is concatenated into another road in-phase end relatively, forms interlocked relationship, as one group of circuit in support wherein, and gives out of order remote signalling amount at first group normally-closed contact, and backstage fault alarm indication is provided.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, it is characterized in that: relay drive circuit is by the signal of voltage comparator circuit output, after drawing on being undertaken by resistance R 5, R6, drive the line bag that Darlington transistor Q1, Q2 come control relay.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device is characterized in that: the relay model that this device is selected is the low-power consumption plate level relay of JW2SN-24V, and coil power dissipation is 0.5W.
Aforesaid novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device is characterized in that: the damping switching control signal that provides from line selection apparatus is provided the route selection interface circuit, realizes the function of resistance route selection in the parallel connection.
Compare with traditional damping control apparatus, the utility model technological merit is as follows:
1. conventional voltage, current signal collection need voltage transformer pt, Current Transmit, and this device directly gathers the damping resistance both end voltage, by entering voltage detecting circuit behind the bleeder circuit, save cost;
2. circuit is directly got damping resistance two ends circuit output voltage signal and is carried out rectification, and Power supply is provided, and saves Switching Power Supply, and circuit is more simple and reliable;
3. this switching device is set the different relay control circuits of two threshold voltages, forms interlocked relationship, one group of circuit in support wherein, and when first group of fault, provide the indication of reporting to the police, further improve the reliability of device;
4. this device has designed resistance Circumscribing port mouth, provides line selection apparatus to realize resistance route selection function in the parallel connection, and saving line selection apparatus needs the extra resistance control loop that increases, and cost performance is higher.
Description of drawings
Fig. 1 is the structure composition diagram of the damp resistance throw-cut device of the utility model embodiment.
Fig. 2 is the circuit working principle assumption diagram of the damp resistance throw-cut device of the utility model embodiment.
Fig. 3 is the turn-adjusting arc-extinguishing winding schematic diagram of the damp resistance throw-cut device of the utility model embodiment.
Fig. 4 is the Quadratic Damping schematic diagram of the damp resistance throw-cut device of the utility model embodiment.
Fig. 5 is the Quadratic Damping equivalent schematic diagram of the damp resistance throw-cut device of the utility model embodiment.
Fig. 6 is the realization flow of resistance route selection in the parallel connection of damp resistance throw-cut device of the utility model embodiment.
Embodiment
In order to understand better the present invention, further illustrate content of the present invention below in conjunction with embodiment, but content of the present invention not only is confined to the following examples.Those skilled in the art can make various changes or modifications the present invention, and these equivalent form of values are equally within the listed claims limited range of the application.
The utility model apparatus structure forms as shown in Figure 1.Mainly formed by rectification circuit, resistor voltage divider circuit, voltage comparator circuit, relay contact interlocking control circuit, relay drive circuit, route selection interface circuit.Resistor voltage divider circuit is mainly realized current limliting and dividing potential drop; Rectification circuit is realized AC-DC conversion, and circuit work power is provided; Damping switching when voltage comparator circuit is realized different voltage threshold.The relay contact interlocking control circuit is realized double protection functions, provides warning when first group of fault, and the backup protection function is provided; Relay drive circuit is mainly realized by comparing the output voltage realization to the power control system of relay coil; The route selection interface is mainly by providing relay to drive interface circuit, and is independent of voltage comparator circuit, realizes resistance switching function according to the signal that line selection apparatus provides.
Device circuit operation principle structure chart as shown in Figure 2.Rectification circuit adopts rectification chip KBP202, and alternating voltage Uro is become DC power supply.Voltage stabilizing and the power voltage stabilizing didoe IN5359B by dc capacitor C1 and 24V carry out voltage stabilizing; wherein voltage stabilizing didoe mainly is to shield; dc capacitor plays voltage stabilizing and flat ripple effect, and the power supply behind the rectifying and voltage-stabilizing provides the working power of chip and relay drive circuit.Resistor voltage divider circuit is comprised of cement resistor R1, R2, R3, and this cement resistor is all chosen high-power resistance, can pass through for a long time the 50mA electric current, by cement resistor damping resistance two ends output voltage U ro is carried out current limliting and dividing potential drop.Voltage comparator circuit carries out dividing potential drop by resistance R 2, R3, R4 to the 24V direct current, obtains two magnitudes of voltage that voltage is different, and this value is the threshold voltage value of comparator.The R4 of access comparator in-phase end is adjustable resistance, and adjusting R4 is the threshold value range of capable of regulating comparator.Wherein the normally-closed contact of a group relay is concatenated into another road in-phase end relatively, forms interlocked relationship, as one group of circuit in support wherein, and gives out of order remote signalling amount at first group normally-closed contact, and backstage fault alarm indication is provided.Relay drive circuit after drawing on being undertaken by R5, R6, drives the line bag that Darlington transistor Q1, Q2 come control relay by the signal of output relatively, and the relay model that this device is selected is the low-power consumption plate level relay of JW2SN-24V, and coil power dissipation only is 0.5W.The damping switching control signal that provides from line selection apparatus mainly is provided the route selection interface circuit, realizes the function of resistance route selection in the parallel connection.
The damping resistance both end voltage is as the principle analysis of damp resistance throw-cut basis for estimation.Be illustrated in figure 4 as the Quadratic Damping fundamental diagram.Damping resistance is connected in parallel on the arc suppression coil secondary winding, and when the turn-adjusting arc-extinguishing winding primary side number of turn changed, arc suppression coil one secondary winding no-load voltage ratio changed, but the Quadratic Damping resistance value is fixed value.Under resistance does not become situation, only need the minimum gear of the number of turn to satisfy the voltage excision condition of damping resistance, then other gear also satisfies this condition.This device draws the damping resistance both end voltage after converting by the no-load voltage ratio of the gear of minimum turn number and secondary winding, adjusts the adjustable resistance on the switching device.Below be that fixed value is analyzed to the Quadratic Damping value.
Such as Quadratic Damping equivalent schematic diagram among Fig. 5, neutral point voltage is
U, system's unbalance voltage is
E,
RBe the damping resistance value after the equivalence,
,
rBe the Quadratic Damping resistance value,
Be number of turn of arc suppression coil,
Be the arc suppression coil secondary number of turn.
In the resonance situation, satisfy relation
The time, substitution is as follows
According to the inductance value computing formula:
In the formula
μ0 is permeability of vacuum,
μS is the relative permeability of coil inside magnetic core,
N1 is wire circle,
SBe the sectional area of coil,
lBe the length of coil,
KCoefficient depend on coil radius (
R) and length (
l) ratio.Therefore,
LSquare be directly proportional with the number of turn of arc suppression coil.In the formula, the number of turn of secondary winding
NThe 2nd, changeless, according to DL/T 1057-2007 standard code, the maximum degree of unbalance of neutral point
EBe 3 (%), and after dropping into damping resistance, central point voltage
UBe no more than then 15 (%), the i.e. value of damping resistance
, therefore, only need damping resistance to satisfy above-mentioned condition, just can get a fixed value.Therefore, when arc suppression coil was in different gear, the ratio of damping that damping resistance produces was consistent to the effect that system produces.Therefore the damping resistance both end voltage can be used as the damp resistance throw-cut basis for estimation.
Figure 6 shows that the flow scheme that resistance is realized in the parallel connection: when permanent single phase ground fault occured in device affirmation system, vacuum contactor was closed, and damping resistance drops into, and injected active current for route selection to system.Therefore because this moment, medium resistance bore very high voltage, through behind the short time delay (less than 1 second) very, vacuum contactor disconnects at once, excision resistance.
The content that is not described in detail in this specification belongs to the known prior art of this area professional and technical personnel.
Claims (7)
1. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device, it is characterized in that, formed by rectification circuit, resistor voltage divider circuit, voltage comparator circuit, relay contact interlocking control circuit, relay drive circuit, route selection interface circuit, the signal of rectification circuit exports voltage comparator circuit and relay contact interlocking control circuit to, realize AC-DC conversion, circuit work power is provided; The signal of resistor voltage divider circuit exports voltage comparator circuit and relay contact interlocking control circuit to, realizes current limliting and dividing potential drop; Voltage comparator circuit is electrically connected with the damping circuit contactor coil, the damping switching when realizing different voltage threshold; The relay contact interlocking control circuit exports the fault alarm module to, realizes double protection functions, provides warning when first group of fault, and the backup protection function is provided; The signal of relay drive circuit exports the relay contact interlocking control circuit to, realizes by comparing the output voltage realization to the control of relay coil; The route selection interface circuit is electrically connected with voltage comparator circuit and relay contact interlocking control circuit, by relay drive circuit is provided, and is independent of voltage comparator circuit, realizes resistance switching function according to the signal that line selection apparatus provides.
2. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 1; it is characterized in that: rectification circuit adopts rectification chip KBP202; alternating voltage Uro is become DC power supply; voltage stabilizing and the power voltage stabilizing didoe by dc capacitor and 24V carry out voltage stabilizing; wherein voltage stabilizing didoe is to shield; dc capacitor plays voltage stabilizing and flat ripple effect, and the power supply behind the rectifying and voltage-stabilizing provides the working power of chip and relay drive circuit.
3. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 1, it is characterized in that: resistor voltage divider circuit is comprised of cement resistor R1, R2, R3, this cement resistor is all chosen high-power resistance, can pass through for a long time the 50mA electric current, by cement resistor damping resistance two ends output voltage U ro be carried out current limliting and dividing potential drop.
4. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 1, it is characterized in that: voltage comparator circuit and relay contact interlocking control circuit carry out dividing potential drop by resistance R 2, R3, R4 to the 24V direct current, obtain two magnitudes of voltage that voltage is different, this value is the threshold voltage value of comparator; The R4 of access comparator in-phase end is adjustable resistance, and adjusting R4 is the threshold value range of capable of regulating comparator; Wherein the normally-closed contact of a group relay is concatenated into another road in-phase end relatively, forms interlocked relationship, as one group of circuit in support wherein, and gives out of order remote signalling amount at first group normally-closed contact, and backstage fault alarm indication is provided.
5. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 1, it is characterized in that: relay drive circuit is by the signal of voltage comparator circuit output, after drawing on being undertaken by resistance R 5, R6, drive the line bag that Darlington transistor Q1, Q2 come control relay.
6. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 5, it is characterized in that: the relay model that this device is selected is the low-power consumption plate level relay of JW2SN-24V, and coil power dissipation is 0.5W.
7. novel turn-adjusting arc-extinguishing winding Quadratic Damping resistance switching device according to claim 1 is characterized in that: the damping switching control signal that the reception of route selection interface circuit provides from line selection apparatus, the function of resistance route selection in the realization parallel connection.
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| CN 201220736176 CN203251090U (en) | 2012-12-28 | 2012-12-28 | Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil |
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| CN 201220736176 CN203251090U (en) | 2012-12-28 | 2012-12-28 | Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103023009A (en) * | 2012-12-28 | 2013-04-03 | 中国电力科学研究院 | Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil |
| CN103944156A (en) * | 2014-04-16 | 2014-07-23 | 江苏汉天星配电自动化科技有限公司 | Grounding forecasting method of arc suppression coil grounding mode |
| CN107611958A (en) * | 2017-08-11 | 2018-01-19 | 国网新源水电有限公司新安江水力发电厂 | Automatic tracking and compensating arc distinction system for generator neutral point |
| CN113189523A (en) * | 2020-01-14 | 2021-07-30 | 山东交通职业学院 | High-voltage interlocking device |
-
2012
- 2012-12-28 CN CN 201220736176 patent/CN203251090U/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103023009A (en) * | 2012-12-28 | 2013-04-03 | 中国电力科学研究院 | Novel turn-adjustable switching device for secondary damping resistor of arc suppression coil |
| CN103944156A (en) * | 2014-04-16 | 2014-07-23 | 江苏汉天星配电自动化科技有限公司 | Grounding forecasting method of arc suppression coil grounding mode |
| CN107611958A (en) * | 2017-08-11 | 2018-01-19 | 国网新源水电有限公司新安江水力发电厂 | Automatic tracking and compensating arc distinction system for generator neutral point |
| CN113189523A (en) * | 2020-01-14 | 2021-07-30 | 山东交通职业学院 | High-voltage interlocking device |
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Granted publication date: 20131023 |