CN108896892B - TXLR type direct current decoupling device for effective grounding system - Google Patents
TXLR type direct current decoupling device for effective grounding system Download PDFInfo
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- CN108896892B CN108896892B CN201811001812.2A CN201811001812A CN108896892B CN 108896892 B CN108896892 B CN 108896892B CN 201811001812 A CN201811001812 A CN 201811001812A CN 108896892 B CN108896892 B CN 108896892B
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- controller
- blocking capacitor
- current
- fixedly arranged
- txlr
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- 230000000903 blocking effect Effects 0.000 claims abstract description 44
- 239000003990 capacitor Substances 0.000 claims abstract description 40
- 230000001629 suppression Effects 0.000 claims abstract description 14
- 230000007935 neutral effect Effects 0.000 claims abstract description 10
- 238000011897 real-time detection Methods 0.000 abstract description 3
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 6
- 238000009413 insulation Methods 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 4
- 239000011787 zinc oxide Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/02—General constructional details
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/08—Limitation or suppression of earth fault currents, e.g. Petersen coil
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a TXLR type direct current decoupling device of an effective grounding system, which comprises a controller ZK, a current limiting reactor L, a current transformer CT, a blocking capacitor C, an electric control cabinet, a valve core voltage limiter, a quick switch controller and an insulating support. The invention connects the blocking capacitor C in series into the neutral point arc suppression coil or the middle and small resistance loops of the AC distribution system, isolates the DC voltage through the blocking capacitor C to ensure the normal use of the on-line real-time detection insulating equipment, rapidly conducts the grounding compensation current of the arc suppression coil grounding system and the small resistance grounding system through the valve core voltage limiter, limits the overvoltage at two ends of the blocking capacitor C, and transmits the current signal of the neutral point loop of the transformer to the controller ZK in real time through the current transformer CT, the controller ZK sends a control electric signal to the rapid switch controller, the rapid switch controller controls the rapid switch to be closed, and ensures the normal operation of the arc suppression coil grounding and the small resistance grounding compensation device.
Description
Technical Field
The invention relates to the technical field of direct current decoupling, in particular to a TXLR type direct current decoupling device of an effective grounding system.
Background
The faults of the power system and the electrical equipment are mostly caused by insulation damage, and the currently internationally recognized insulation detection method is a direct current superposition method: superposing a direct-current voltage signal on an alternating-current high-voltage system or electrical equipment in operation, and converting the current value generated by the insulation of the direct-current voltage to the ground through the system into the insulation level of the system to the ground; in a system in which a neutral point of a high-voltage transformer is grounded through a small resistor or an arc suppression coil, in order to detect the insulation level of the power transmission system to the ground in real time on line, a direct current decoupling device is connected between the small resistor or the arc suppression coil and the ground to ensure the normal use of the insulation equipment to be detected in real time on line, and meanwhile, the influence of a decoupling capacitor element on the compensation current of the neutral point small resistor and the arc suppression coil when the power transmission system breaks down can be solved.
Disclosure of Invention
The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, one purpose of the invention is to provide a TXLR-type direct current decoupling device of an effective grounding system, which is connected between a small resistor or an arc suppression coil and grounding electricity, so as to ensure the normal use of an insulating device in real time on line, and simultaneously conduct fault current to prevent the abnormality of the compensation function of the small resistor and the arc suppression coil.
According to the TXLR type direct current decoupling device of the effective grounding system, which is disclosed by the embodiment of the invention; including controller ZK, current-limiting reactor L, current transformer CT, blocking electric capacity ware C, automatically controlled cabinet, case voltage limiter, fast switch controller, insulating support, the inside left side of automatically controlled cabinet sets up blocking electric capacity ware C, blocking electric capacity ware C fixed mounting is in automatically controlled cabinet bottom, blocking electric capacity ware C upside sets up current-limiting reactor L, current-limiting reactor L is fixed through the device cabinet inner support, is located blocking electric capacity ware C upper portion, current-limiting reactor L upside sets up controller ZK, controller ZK fixed mounting is in on the automatically controlled cabinet inner wall, current-limiting reactor L passes through the insulating support is fixed, blocking electric capacity ware C right side sets up fast switch controller, fast switch controller fixed mounting is in automatically controlled cabinet bottom, fast switch fixed mounting is in fast switch controller upper portion, fast switch left side sets up the case voltage limiter, fast switch fixed mounting is in two poles of the case.
Preferably, the grounding end of the blocking capacitor C is connected with a current transformer CT in series, and the current transformer CT is fixedly arranged on the right side of the blocking capacitor C.
Preferably, the blocking capacitor C and the current limiting reactor L are connected in series to form a first circuit, the valve core voltage limiter and the fast switch are connected in parallel to form a second circuit, the second circuit is connected in series with the current transformer CT, the signal output end of the current transformer CT is electrically connected with the signal input end of the controller ZK, and the signal output end of the controller ZK is electrically connected with the signal input end of the fast switch.
Preferably, the second circuit is connected in series to a neutral point arc suppression coil or a medium-low resistance loop of the alternating current power distribution system.
In the invention, when the high-voltage transmission system normally operates, a TXLR type effective grounding system direct-current decoupling device connects a blocking capacitor C in series into neutral point arc suppression coils or medium and small resistance loops of the alternating-current distribution system, the direct-current voltage is isolated through the blocking capacitor C so as to ensure the normal use of on-line real-time detection insulating equipment, the grounding compensation current of the arc suppression coil grounding system and the small resistance grounding system is quickly conducted through a valve core voltage limiter, the overvoltage at two ends of the blocking capacitor C is limited, when the alternating-current distribution system is grounded, the valve core voltage limiter is conducted, the blocking capacitor C is led to exit the grounding compensation loops of the arc suppression coil grounding system and the small resistance grounding system, the current signal of the neutral point loop of a transformer is transmitted to a controller ZK in real time through a current transformer CT, the controller ZK sends a control electric signal to a quick switch controller, the quick switch controller controls the quick switch to be closed, the stored energy in the blocking capacitor C is released, and the normal operation of the blocking capacitor C is ensured through the valve core voltage limiter and the quick switch double bypass, and the blocking capacitor C is grounded and the small resistance grounding compensation device.
Drawings
The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention. In the drawings:
Fig. 1 is a front view of a dc decoupling device of TXLR type active grounding system according to the present invention;
Fig. 2 is a left side view of a dc decoupling device for TXLR-type active grounding system according to the present invention;
Fig. 3 is a right side view of a dc decoupling device for TXLR-type active grounding system according to the present invention;
Fig. 4 is a schematic circuit diagram of a dc decoupling device of TXLR type active grounding system according to the present invention;
Fig. 5 is a schematic circuit connection diagram of a dc decoupling device for TXLR-type active grounding system according to the present invention.
In the figure: 1-controller ZK, 2-current limiting reactor L, 3-current transformer CT, 4-blocking capacitor C, 5-electric control cabinet, 6-case voltage limiter, 7-fast switch, 8-fast switch controller, 9-insulating support.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments.
Examples of the embodiments are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements throughout or elements having like or similar functionality. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
Referring to fig. 1-3, a direct current decoupling device of a txlr type effective grounding system comprises a controller ZK 1, a current limiting reactor L2, a current transformer CT 3, a blocking capacitor C4, an electric control cabinet 5, a valve core voltage limiter 6, a fast switch 7, a fast switch controller 8 and an insulating support 9, wherein the blocking capacitor C4 is arranged at the left side inside the electric control cabinet 5, the blocking capacitor C4 is fixedly arranged at the bottom of the electric control cabinet 5, the current limiting reactor L2 is arranged at the upper side of the blocking capacitor C4, the current limiting reactor L2 is fixed through a bracket in the device cabinet and is positioned at the upper part of the blocking capacitor C4, the controller ZK 1 is arranged at the upper side of the current limiting reactor L2, the controller ZK 1 is fixedly arranged on the inner wall of the electric control cabinet 5, the current limiting reactor L2 is fixed through the insulating support 9, the fast switch controller 8 is arranged at the right side of the blocking capacitor C4, the fast switch controller 8 is fixedly arranged at the bottom of the electric control cabinet 5, the fast switch 7 is fixedly arranged at the upper part of the fast switch controller 8, the fast switch 7 is arranged at the left side of the blocking capacitor C4, and the valve cores are fixedly arranged at the two valve cores 7 and are fixedly arranged at the valve cores of the two limiting reactors; the grounding end of the blocking capacitor C4 is connected with a current transformer CT 3 in series, and the current transformer CT 3 is fixedly arranged on the right side of the blocking capacitor C4.
As shown in fig. 4-5, the blocking capacitor C4 and the current limiting reactor L2 are connected in series to form a first circuit, the valve core voltage limiter 6 and the fast switch 7 are connected in parallel to form a second circuit, the second circuit is connected in series with the current transformer CT 3, the signal output end of the current transformer CT 3 is connected with the signal input end of the controller ZK 1 by an electric signal, and the signal output end of the controller ZK 1 is connected with the signal input end of the fast switch 7 by an electric signal; the second circuit is connected in series to a neutral point arc suppression coil or a medium-small resistance loop of the alternating current power distribution system.
Dc blocking capacitor C: the model is HCDC-2KV 50UF, and is used for isolating a system direct current measurement signal, and a valve core voltage limiter: the model is HDJ0-3000, zinc oxide nonlinear resistor MOV is adopted, and is used for limiting overvoltage at two ends of the blocking capacitor C when impact current occurs to a circuit; current limiting reactor L: the model is HDL-200-50, which is used for limiting the intensity of the discharge current when the blocking capacitor C discharges and preventing the blocking capacitor C from being damaged due to overcurrent; and (3) fast switching: the model is VFC-12/400, and is used for rapidly shorting the zinc oxide nonlinear resistor MOV when overcurrent occurs on a circuit, preventing the zinc oxide nonlinear resistor MOV from long-time current passing, and the current transformer CT: model LMZ-0.5, which is used to detect the current in the circuit and transmit to the controller ZK in real time; controller ZK: the control circuit is used for detecting the current of the line, monitoring the running condition of the line in real time, and sending a switching-on and switching-off command to the fast switch controller when the current exceeds a set value or when a manual signal of the panel is received.
In summary, in the invention, when the high-voltage transmission system normally operates, the TXLR type effective grounding system direct-current decoupling device strings the blocking capacitor C into the neutral point loop of the transformer, the direct-current voltage is isolated through the blocking capacitor C, so as to ensure the normal use of the on-line real-time detection insulating equipment.
In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.
Claims (3)
- TXLR type effective grounding system direct current decoupling device is characterized in that: the intelligent control system comprises a controller ZK, a current limiting reactor L, a current transformer CT, a blocking capacitor C, an electric control cabinet, a valve core voltage limiter, a quick switch controller and an insulating support, wherein the blocking capacitor C is arranged on the left side inside the electric control cabinet, the blocking capacitor C is fixedly arranged at the bottom of the electric control cabinet, the current limiting reactor L is arranged on the upper side of the blocking capacitor C and is fixed through a bracket in the device cabinet, the current limiting reactor L is positioned on the upper part of the blocking capacitor C, the controller ZK is arranged on the upper side of the current limiting reactor L, the controller ZK is fixedly arranged on the inner wall of the electric control cabinet, the current limiting reactor L is fixedly arranged through the insulating support, the quick switch controller is fixedly arranged on the bottom of the electric control cabinet, the quick switch is fixedly arranged on the upper part of the quick switch controller, the valve core voltage limiter is arranged on the left side of the quick switch, and the valve core voltage limiter is fixedly arranged on the two poles of the quick switch;The blocking capacitor C and the current limiting reactor L are connected in series to form a first circuit, the valve core voltage limiter and the fast switch are connected in parallel to form a second circuit, the second circuit is connected in series with the current transformer CT, the signal output end of the current transformer CT is connected with the signal input end of the controller ZK in an electric signal manner, and the signal output end of the controller ZK is connected with the signal input end of the fast switch in an electric signal manner.
- 2. The TXLR-type active ground system dc decoupling device of claim 1, wherein: the grounding end of the blocking capacitor C is connected with a current transformer CT in series, and the current transformer CT is fixedly arranged on the right side of the blocking capacitor C.
- 3. The TXLR-type active ground system dc decoupling device of claim 1, wherein: the second circuit is connected in series to a neutral point arc suppression coil or a medium-small resistance loop of the alternating current power distribution system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811001812.2A CN108896892B (en) | 2018-08-30 | 2018-08-30 | TXLR type direct current decoupling device for effective grounding system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811001812.2A CN108896892B (en) | 2018-08-30 | 2018-08-30 | TXLR type direct current decoupling device for effective grounding system |
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| CN108896892A CN108896892A (en) | 2018-11-27 |
| CN108896892B true CN108896892B (en) | 2024-05-31 |
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| CN201811001812.2A Active CN108896892B (en) | 2018-08-30 | 2018-08-30 | TXLR type direct current decoupling device for effective grounding system |
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| WO2024082131A1 (en) * | 2022-10-18 | 2024-04-25 | Siemens Aktiengesellschaft | Converter and control method thereof, electrical device and readable storage medium |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11215713A (en) * | 1998-01-20 | 1999-08-06 | Nissin Electric Co Ltd | System fault current detector |
| CN2847637Y (en) * | 2005-11-18 | 2006-12-13 | 中国电力科学研究院 | Device for suppressing transformer neutral point DC current by capacitance method |
| CN102623985A (en) * | 2012-01-17 | 2012-08-01 | 合肥凯高电气设备有限公司 | Novel comprehensive grounding protection and route selection device for medium-voltage power distribution system |
| CN202503284U (en) * | 2012-03-28 | 2012-10-24 | 上海市电力公司 | Capacitance-type direct current inhibiting device |
| CN204794061U (en) * | 2015-07-27 | 2015-11-18 | 国家电网公司 | Transformer dc magnetic biasing suppression device based on multipleization technique |
| CN204903656U (en) * | 2015-08-04 | 2015-12-23 | 国网浙江桐乡市供电公司 | A device for arc suppressing coil ground system measuring circuit direct -to -ground capacitance |
| CN105391028A (en) * | 2015-11-05 | 2016-03-09 | 国网四川省电力公司电力科学研究院 | Neutral-point direct-current elimination resistance-capacitance device of transformer and method |
| CN209086373U (en) * | 2018-08-30 | 2019-07-09 | 北京中联太信科技有限公司 | TXLR type effectively earthed system direct current decoupling device |
-
2018
- 2018-08-30 CN CN201811001812.2A patent/CN108896892B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11215713A (en) * | 1998-01-20 | 1999-08-06 | Nissin Electric Co Ltd | System fault current detector |
| CN2847637Y (en) * | 2005-11-18 | 2006-12-13 | 中国电力科学研究院 | Device for suppressing transformer neutral point DC current by capacitance method |
| CN102623985A (en) * | 2012-01-17 | 2012-08-01 | 合肥凯高电气设备有限公司 | Novel comprehensive grounding protection and route selection device for medium-voltage power distribution system |
| CN202503284U (en) * | 2012-03-28 | 2012-10-24 | 上海市电力公司 | Capacitance-type direct current inhibiting device |
| CN204794061U (en) * | 2015-07-27 | 2015-11-18 | 国家电网公司 | Transformer dc magnetic biasing suppression device based on multipleization technique |
| CN204903656U (en) * | 2015-08-04 | 2015-12-23 | 国网浙江桐乡市供电公司 | A device for arc suppressing coil ground system measuring circuit direct -to -ground capacitance |
| CN105391028A (en) * | 2015-11-05 | 2016-03-09 | 国网四川省电力公司电力科学研究院 | Neutral-point direct-current elimination resistance-capacitance device of transformer and method |
| CN209086373U (en) * | 2018-08-30 | 2019-07-09 | 北京中联太信科技有限公司 | TXLR type effectively earthed system direct current decoupling device |
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