CN113036715A - Control loop capable of improving anti-interference capability of non-electric quantity protection device of transformer - Google Patents
Control loop capable of improving anti-interference capability of non-electric quantity protection device of transformer Download PDFInfo
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- CN113036715A CN113036715A CN202110508754.8A CN202110508754A CN113036715A CN 113036715 A CN113036715 A CN 113036715A CN 202110508754 A CN202110508754 A CN 202110508754A CN 113036715 A CN113036715 A CN 113036715A
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- 230000009471 action Effects 0.000 claims description 8
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 6
- 230000006872 improvement Effects 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 5
- 239000010959 steel Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
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- 238000009413 insulation Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 1
- 230000037396 body weight Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
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- 229910052742 iron Inorganic materials 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/02—Details
- H02H3/05—Details with means for increasing reliability, e.g. redundancy arrangements
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Abstract
The invention discloses a control loop capable of improving the anti-interference capability of a non-electric quantity protection device of a transformer, which comprises the following operation steps: s1, isolating interference: the internal capacitor is generally arranged in the component of the electric circuit, so that the isolation effect of the intermediate relay can be utilized, and the interference effect of the stray capacitor on the non-electric fault signal can be realized by additionally arranging the intermediate relay element in the control circuit of the non-electric protection device. The invention can eliminate the hidden trouble of malfunction tripping caused by the grounding fault of the direct current power supply system to the non-electric quantity protection device of the transformer by improving and optimizing the control loop of the non-electric quantity protection device of the transformer, provides practical guarantee for the safe and stable operation of the transformer, and has the beneficial effects that: the malfunction tripping fault of the non-electric quantity protection device of the transformer is eliminated, the fault rate of the transformer is reduced, and the safe and stable operation of the transformer is ensured.
Description
Technical Field
The invention relates to the technical field of control loops, in particular to a control loop capable of improving the anti-interference capability of a non-electric quantity protection device of a transformer.
Background
At present, the known non-electric quantity protection refers to the fault action reflected by non-electric quantity parameters, generally refers to that the criterion of protection is not electric quantity parameters (current, voltage, frequency, impedance and the like), but non-electric quantity parameters, such as gas protection (through oil speed setting), temperature protection (through temperature regulation), explosion protection (through pressure relief valve limitation) and the like, a control loop of a non-electric quantity protection device of the transformer consists of an external direct current +/-110V power supply, a plurality of external dry contacts, a transformer comprehensive protection device and the like, non-electric quantity fault signals (mainly comprising body weight gas, pressure relief, body light gas, high oil temperature and the like) transmitted from a transformer body are input into the non-electric quantity protection device through a switching value input end, after receiving the fault signals, the protection device determines whether to trip or send an alarm according to the content of the control characters.
The control loop of the transformer non-electric protection device used in a plurality of steel plants at present is the control loop directly connected to the transformer comprehensive protection device by an external dry contact, and the control loop have trip faults caused by misoperation of the control loop of the transformer non-electric protection device for a plurality of times in the past use process, and the main performance of the faults is as follows: the comprehensive protection device of the transformer shows that the non-electric quantity protection device has protective tripping action, but after checking the transformer body, the related non-electric quantity protection parameters of the transformer body do not reach action values, then a relay protection test is carried out on the non-electric quantity protection device, the abnormality is not found, then a control loop of the non-electric quantity protection device is carefully checked, wherein the abnormality is not found in the wiring of a control box of the transformer body, the setting value verification of a relay, the test of a direct current control power supply system and the like, finally the reason of causing the tripping fault is found to be caused by the reduction of the insulation degree of a direct current power supply cable, and after the direct current power supply cable is replaced to eliminate the grounding phenomenon of the direct current power supply system, the tripping fault of the non-electric quantity protection device is eliminated, and the phenomenon that the non-electric quantity protection device of the transformer generates misoperation and tripping fault frequently occurs is caused, the reason for this is that there is a certain potential fault in the secondary control loop.
The control loop of the traditional transformer non-electric quantity protection device has the following problems in operation:
1. the direct current power supply system generates a ground fault: the direct current power supply system is used as an important component of a secondary control loop system, and is a direct current power supply of a relay and an automatic protection device and the like, the power load of the direct current power supply system is very important, the requirement on the reliability of power supply is very high, when the fault of the direct current power supply occurs in the relay and the automatic protection device or in the loop of a switching-on and switching-off switch, the relay and the automatic protection device can generate false operation, because a common tripping and switching-off coil is usually connected with the negative electrode of the direct current power supply, if the positive electrode (+1KM) of the power supply passes through a normally open contact of a temperature controller of a transformer through a stray capacitor to form a loop with a non-electric quantity protection device, the false operation can be caused, after the on-site control loop is checked one by one, the insulation value of a control cable of a converter 2# 1 boiler feed pump frequency converter cabinet is found to be reduced, and the result of measuring the, The voltage to earth of the direct current power supply is +/-110V under a normal state, and the problem of false operation and tripping of a control loop of the non-electric quantity protection device of the transformer can be caused due to the fact that the voltages of the positive electrode and the negative electrode of the direct current power supply system are reduced;
2. there is a stray capacitance in the electrical circuit: in the actual working condition, all electrical components such as inductance elements, diodes, transistors and the like have internal capacitors, and the non-electric protection device of the transformer consists of the inductance elements, the diodes, the transistors and the like, so that the condition that the non-electric protection device of the transformer has the internal capacitors cannot be avoided, a plurality of high-voltage switch cabinets are arranged in each high-voltage electric room of a steel and iron steel plant, a plurality of direct-current control loops are arranged, the length of a control cable laid on the site is long, the generated stray capacitor is large, and the corresponding induction voltage is also large, therefore, once a grounding fault occurs in a direct-current power supply system, the control loop of the non-electric protection device can easily generate corresponding false operation reaction;
the differential pressure between the stray capacitor and the negative pole of the direct current power supply in a normal direct current power supply system is-110V, when the direct current power supply system is grounded, the voltages of the positive pole and the negative pole of the direct current power supply are reduced, the differential pressure between the stray capacitor and the negative pole of the direct current power supply is increased, when the differential pressure is larger than-140V, a non-electric quantity protection device control loop defaults to have non-electric quantity fault signal feedback to send a signal, when the protection device receives the non-electric quantity fault signal, whether the protection device trips or sends an alarm is determined according to the content of a control character, if the non-electric quantity protection device of the transformer trips in a false action, serious influence and economic loss are caused to steel-making production.
Therefore, the original control loop of the transformer non-electric quantity protection device directly connected to the comprehensive protection device of the transformer from the external dry contact has weak anti-interference capability, and needs to be improved and optimized to improve the reliability and stability of the operation of the control loop and finally achieve the aim of eliminating the malfunction tripping fault.
Disclosure of Invention
Aiming at the defects in the background technology, the invention provides a control loop capable of improving the anti-interference capability of a non-electric quantity protection device of a transformer.
In order to solve the above phenomenon, the invention adopts the following technical scheme that a control loop capable of improving the anti-interference capability of a non-electric quantity protection device of a transformer is prepared by the following steps:
s1, isolating interference: the components of the electric circuit are generally provided with internal capacitors, so that the isolation effect of an intermediate relay can be utilized, and the interference effect of stray capacitors on non-electric quantity fault signals can be isolated by additionally arranging an intermediate relay element in a control circuit of the non-electric quantity protection device;
s2, intermediate relay: a1 and A2 of an intermediate relay GWJ are inserted between an external dry contact of a transformer of +110V of a direct-current power supply and a terminal of-110V, and then the intermediate relay is connected to a non-electric quantity protection device of the transformer through an auxiliary contact of the intermediate relay;
s3, operation processing: when the external dry contact of the transformer acts and closes due to the fact that the external dry contact receives the non-electric quantity fault signal, the GWJ coil of the intermediate relay is electrified, so that the normally open auxiliary contact of the intermediate relay is closed to trigger the action of the non-electric quantity protection device, and the protection device determines whether to trip or send an alarm according to the content of the control character after receiving the non-electric quantity fault signal transmitted by the protection device.
As a further preferable mode of the present invention, in step S1, the improved microcomputer relay non-electric fault signal input principle has stronger reliability and is more suitable for a complicated use environment compared with the original one, and simultaneously, the malfunction trip fault of the non-electric protection device can be eliminated, and the safe and stable operation of the transformer can be ensured.
As a further preferred embodiment of the present invention, in step S2, the stray capacitance in the control loop of the original non-electrical protection device can be isolated, so as to enhance the anti-interference capability of the control loop of the device.
As a further preferable mode of the present invention, in step S3, the isolation function of the intermediate relay is used to isolate and eliminate various external influencing factors that influence the non-electric fault signal of the transformer, so as to avoid the malfunction and trip fault of the non-electric protection device of the transformer and ensure the safe and stable operation of the transformer.
The control loop capable of improving the anti-interference capability of the transformer non-electric quantity protection device is a simple, practical and efficient anti-interference control loop, can effectively prevent false operation faults of the transformer non-electric quantity protection device by using the control loop, ensures safe and stable operation of the transformer, can eliminate hidden troubles of false operation tripping caused by the ground fault of a direct-current power supply system to the transformer non-electric quantity protection device by improving and optimizing the control loop of the transformer non-electric quantity protection device, can effectively improve the operation reliability and stability of the control loop of the device, provides practical guarantee for safe and stable operation of the transformer, and has the beneficial effects of: the malfunction tripping fault of the non-electric quantity protection device of the transformer is eliminated, the fault rate of the transformer is reduced, and the safe and stable operation of the transformer is ensured.
Drawings
FIG. 1 is a flow chart of the operation of the present invention;
fig. 2 is a first malfunction trip fault phenomenon diagram of the present invention;
fig. 3 is a second malfunction trip fault phenomenon diagram of the present invention;
FIG. 4 is a schematic diagram of a control loop of a non-electric protection device for a transformer before improvement of the present invention;
FIG. 5 is a schematic diagram of a control loop of the improved non-electric protection device for the transformer according to the present invention;
FIG. 6 is a schematic diagram of the input of a non-electrical fault signal of a microcomputer relay before the improvement of the present invention;
FIG. 7 is a schematic diagram of the input of a non-electrical fault signal of a microcomputer relay according to the improvement of the present invention;
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a technical scheme that: a control loop capable of improving the anti-interference capability of a non-electric quantity protection device of a transformer is prepared by the following steps:
s1, isolating interference: the components of the electric circuit are generally provided with internal capacitors, so that the isolation effect of an intermediate relay can be utilized, and the interference effect of stray capacitors on non-electric quantity fault signals can be isolated by additionally arranging an intermediate relay element in a control circuit of the non-electric quantity protection device;
s2, intermediate relay: a1 and A2 of an intermediate relay GWJ are inserted between an external dry contact of a transformer of +110V of a direct-current power supply and a terminal of-110V, and then the intermediate relay is connected to a non-electric quantity protection device of the transformer through an auxiliary contact of the intermediate relay;
s3, operation processing: when the external dry contact of the transformer acts and closes due to the fact that the external dry contact receives the non-electric quantity fault signal, the GWJ coil of the intermediate relay is electrified, so that the normally open auxiliary contact of the intermediate relay is closed to trigger the action of the non-electric quantity protection device, and the protection device determines whether to trip or send an alarm according to the content of the control character after receiving the non-electric quantity fault signal transmitted by the protection device.
In step S1, the improved microcomputer relay non-electric fault signal input principle has stronger reliability and is more suitable for complex use environment compared with the original one, and meanwhile, the malfunction tripping fault of the non-electric protection device can be eliminated, and the safe and stable operation of the transformer can be ensured.
In step S2, the stray capacitance in the control loop of the original non-electrical protection device can be isolated, so as to enhance the anti-interference capability of the control loop of the device.
In step S3, the isolation function of the intermediate relay is used to isolate and eliminate various external influence factors that affect the non-electric fault signal of the transformer, thereby avoiding the non-electric protection device of the transformer from generating malfunction tripping faults and ensuring the safe and stable operation of the transformer.
Example one
The invention provides a technical scheme that: a chemical fiber composite material and a preparation method thereof, the preparation method comprises the following steps:
s1, isolating interference: the components of the electric circuit are generally provided with internal capacitors, so that the isolation effect of an intermediate relay can be utilized, and the interference effect of stray capacitors on non-electric quantity fault signals can be isolated by additionally arranging an intermediate relay element in a control circuit of the non-electric quantity protection device;
s2, intermediate relay: a1 and A2 of an intermediate relay GWJ are inserted between an external dry contact of a transformer of +110V of a direct-current power supply and a terminal of-110V, and then the intermediate relay is connected to a non-electric quantity protection device of the transformer through an auxiliary contact of the intermediate relay;
s3, operation processing: when the external dry contact of the transformer acts and closes due to the fact that the external dry contact receives the non-electric quantity fault signal, the GWJ coil of the intermediate relay is electrified, so that the normally open auxiliary contact of the intermediate relay is closed to trigger the action of the non-electric quantity protection device, and the protection device determines whether to trip or send an alarm according to the content of the control character after receiving the non-electric quantity fault signal transmitted by the protection device.
In step S1, the improved microcomputer relay non-electric fault signal input principle has stronger reliability and is more suitable for complex use environment compared with the original one, and meanwhile, the malfunction tripping fault of the non-electric protection device can be eliminated, and the safe and stable operation of the transformer can be ensured.
In step S2, the stray capacitance in the control loop of the original non-electrical protection device can be isolated, so as to enhance the anti-interference capability of the control loop of the device.
In step S3, the isolation function of the intermediate relay is used to isolate and eliminate various external influence factors that affect the non-electric fault signal of the transformer, thereby avoiding the non-electric protection device of the transformer from generating malfunction tripping faults and ensuring the safe and stable operation of the transformer.
After the Zhanjiang steel mill carries out improvement and optimization on the control loop of the non-electric-quantity protection device on 3 transformers according to the improvement technical scheme of the invention, the 3 transformers have no fault tripping event of the non-electric-quantity protection device caused by the ground fault of the direct-current power supply system.
Next, a comparison statistic is performed on the number of times of ground faults of a direct-current power supply system in a high-voltage electric room of a comprehensive building in north area of the Zhanjiang steel plant in 2018 from 8 months to 10 months and the corresponding number of times of malfunction tripping faults of a modified transformer non-electric-quantity protection device.
It can be known from the table that when the dc power system has a ground fault, the number of times that the non-electric quantity protection device generates the malfunction trip fault reaches 2 times for the transformer without improvement, and there is no malfunction trip fault of the non-electric quantity protection device due to the ground fault of the dc power system for the 3 improved power supply transformers.
In summary, the control loop capable of improving the anti-interference capability of the transformer non-electric quantity protection device is a simple, practical and efficient anti-interference control loop, and by using the control loop, the false operation fault of the transformer non-electric quantity protection device can be effectively prevented, the safe and stable operation of the transformer is ensured, and by improving and optimizing the control loop of the transformer non-electric quantity protection device, the hidden danger of false operation tripping caused by the ground fault of a direct current power supply system to the transformer non-electric quantity protection device can be eliminated, so that the operation reliability and stability of the control loop of the device can be effectively improved, the safe and stable operation of the transformer is practically guaranteed, and the beneficial effects are finally reflected: the malfunction tripping fault of the non-electric quantity protection device of the transformer is eliminated, the fault rate of the transformer is reduced, and the safe and stable operation of the transformer is ensured.
While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (4)
1. A control loop capable of improving the anti-interference capability of a transformer non-electric quantity protection device is characterized in that the operation steps comprise the following steps:
s1, isolating interference: the components of the electric circuit are generally provided with internal capacitors, so that the isolation effect of an intermediate relay can be utilized, and the interference effect of stray capacitors on non-electric quantity fault signals can be isolated by additionally arranging an intermediate relay element in a control circuit of the non-electric quantity protection device;
s2, intermediate relay: a1 and A2 of an intermediate relay GWJ are inserted between an external dry contact of a transformer of +110V of a direct-current power supply and a terminal of-110V, and then the intermediate relay is connected to a non-electric quantity protection device of the transformer through an auxiliary contact of the intermediate relay;
s3, operation processing: when the external dry contact of the transformer acts and closes due to the fact that the external dry contact receives the non-electric quantity fault signal, the GWJ coil of the intermediate relay is electrified, so that the normally open auxiliary contact of the intermediate relay is closed to trigger the action of the non-electric quantity protection device, and the protection device determines whether to trip or send an alarm according to the content of the control character after receiving the non-electric quantity fault signal transmitted by the protection device.
2. The control circuit of claim 1, wherein in step S1, the improved microcomputer relay non-electric fault signal input principle has higher reliability and is more suitable for complex use environment compared with the original one, and meanwhile, the control circuit can eliminate malfunction tripping fault of the non-electric protection device and ensure safe and stable operation of the transformer.
3. The control loop of claim 1, wherein in step S2, the stray capacitance in the control loop of the original non-electrical protection device is isolated, so as to enhance the anti-interference capability of the control loop of the device.
4. The control circuit of claim 1, wherein in step S3, the isolation function of the intermediate relay is used to isolate and eliminate various external influencing factors affecting the non-electric fault signal of the transformer, so as to prevent the non-electric protection device of the transformer from generating malfunction tripping faults and ensure the safe and stable operation of the transformer.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110508754.8A CN113036715A (en) | 2021-05-11 | 2021-05-11 | Control loop capable of improving anti-interference capability of non-electric quantity protection device of transformer |
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| CN202110508754.8A CN113036715A (en) | 2021-05-11 | 2021-05-11 | Control loop capable of improving anti-interference capability of non-electric quantity protection device of transformer |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113872167A (en) * | 2021-11-24 | 2021-12-31 | 国网重庆市电力公司电力科学研究院 | Device and method for preventing protection misoperation or refusal caused by direct current system ground fault |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203747378U (en) * | 2014-03-13 | 2014-07-30 | 攀钢集团攀枝花钢钒有限公司 | Transformer microcomputer protection system |
| CN206148927U (en) * | 2016-11-23 | 2017-05-03 | 陈楠 | Power transformer's gas protection device |
| CN109617003A (en) * | 2019-01-02 | 2019-04-12 | 国网福建省电力有限公司莆田供电公司 | A kind of secondary control cable distributed capacitance causes the elimination circuit of protection act |
| CN209747409U (en) * | 2019-05-23 | 2019-12-06 | 江苏国信淮安第二燃气发电有限责任公司 | High-power malfunction-prevention contactor type intermediate relay |
-
2021
- 2021-05-11 CN CN202110508754.8A patent/CN113036715A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203747378U (en) * | 2014-03-13 | 2014-07-30 | 攀钢集团攀枝花钢钒有限公司 | Transformer microcomputer protection system |
| CN206148927U (en) * | 2016-11-23 | 2017-05-03 | 陈楠 | Power transformer's gas protection device |
| CN109617003A (en) * | 2019-01-02 | 2019-04-12 | 国网福建省电力有限公司莆田供电公司 | A kind of secondary control cable distributed capacitance causes the elimination circuit of protection act |
| CN209747409U (en) * | 2019-05-23 | 2019-12-06 | 江苏国信淮安第二燃气发电有限责任公司 | High-power malfunction-prevention contactor type intermediate relay |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113872167A (en) * | 2021-11-24 | 2021-12-31 | 国网重庆市电力公司电力科学研究院 | Device and method for preventing protection misoperation or refusal caused by direct current system ground fault |
| CN113872167B (en) * | 2021-11-24 | 2024-05-28 | 国网重庆市电力公司电力科学研究院 | Device and method for preventing protection misoperation or refusal operation caused by direct current system ground fault |
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