CN111856179A - Transformer substation secondary grounding monitoring device and method - Google Patents
Transformer substation secondary grounding monitoring device and method Download PDFInfo
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- CN111856179A CN111856179A CN202010587041.0A CN202010587041A CN111856179A CN 111856179 A CN111856179 A CN 111856179A CN 202010587041 A CN202010587041 A CN 202010587041A CN 111856179 A CN111856179 A CN 111856179A
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- 238000012806 monitoring device Methods 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000001514 detection method Methods 0.000 claims abstract description 18
- 238000006243 chemical reaction Methods 0.000 claims abstract description 14
- 238000012544 monitoring process Methods 0.000 claims abstract description 9
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 6
- 240000007651 Rubus glaucus Species 0.000 claims description 4
- 235000011034 Rubus glaucus Nutrition 0.000 claims description 4
- 235000009122 Rubus idaeus Nutrition 0.000 claims description 4
- 230000015556 catabolic process Effects 0.000 claims description 3
- 230000007797 corrosion Effects 0.000 claims description 3
- 238000005260 corrosion Methods 0.000 claims description 3
- 230000009467 reduction Effects 0.000 claims description 3
- 239000011787 zinc oxide Substances 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 230000008569 process Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
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Classifications
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- 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/20—Measuring earth resistance; Measuring contact resistance, e.g. of earth connections, e.g. plates
-
- 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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00001—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by the display of information or by user interaction, e.g. supervisory control and data acquisition systems [SCADA] or graphical user interfaces [GUI]
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00002—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by monitoring
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00032—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for
- H02J13/00034—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for the elements or equipment being or involving an electric power substation
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Power Engineering (AREA)
- Human Computer Interaction (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention relates to a transformer substation secondary grounding monitoring device and a method. The alarm display module has four alarm modes; the conversion module comprises resistance detection wires with different numbers, and the resistance detection wires are connected with zero lines of a current transformer or a voltage transformer, so that the secondary grounding monitoring device of the transformer substation can simultaneously monitor the grounding loop resistance values with the same number as the resistance detection wires. The invention realizes the automatic real-time monitoring of the secondary grounding condition of the transformer substation, provides the fault problem under different modes of alarming for the working personnel, and is beneficial to the quick fault solving and the operation and maintenance of the transformer substation for the working personnel.
Description
Technical Field
The invention belongs to the field of relay protection, and particularly relates to a secondary grounding monitoring device and method for a transformer substation.
Background
The grounding of a secondary system of a transformer substation mainly has the functions of protecting personal safety and shielding interference signals, if the secondary grounding has problems such as virtual connection or multipoint grounding, incorrect protection action caused by inaccurate sampling values of a voltage loop and a current loop can be caused, a certain 500kV transformer substation has two-point grounding of the current loop, when fault current passes through a grounding network or is in a strong magnetic field, small potential difference occurs between two grounding points on the grounding network, and false protection action is caused after the interference current is normally sampled and superposed. A220 kV power transmission system in a certain area is provided with high-frequency zero sequence protection, when a fault that a bus B is grounded occurs in 7 months and 9 days in 09 years, the zero sequence protection direction is misjudged, and then the fault is analyzed by a wave recording diagram to be caused by PT two-point grounding. If the secondary grounding virtual connection is adopted, overvoltage can be caused, and therefore damage to equipment and personnel can be caused. At present, secondary equipment of a transformer substation does not have an automatic monitoring means aiming at the grounding condition of a secondary system, and only can check a secondary wiring process by depending on the checking and accepting process, in addition, secondary circuits are checked by depending on personnel in the technical improvement and overhaul process of the transformer substation, generally, a current method, a signal injection method, an unbalanced load current method, a phase comparison method and the like can be adopted, the manual operation process is complex, the automation degree is low, and problems cannot be found in time.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a transformer substation secondary grounding monitoring device and method, which can automatically monitor the secondary grounding condition of a transformer substation.
The technical problem to be solved by the invention is realized by adopting the following technical scheme:
the utility model provides a transformer substation's secondary ground monitoring device which characterized in that: the device comprises a direct resistance testing module, a control module, a conversion module and an alarm display module which are connected in sequence.
Moreover, the direct resistance testing module uses a direct current resistance tester, the control module uses a raspberry pi, and the conversion module uses a programmable relay.
Moreover, the alarm display module has four alarm modes.
And the conversion module outputs resistance detection wires with different numbers, and the resistance detection wires are connected with zero lines of the current transformer or the voltage transformer.
A monitoring method of a secondary grounding monitoring device of a transformer substation comprises the following steps:
step 1, giving an initial value R to a corresponding grounding loop according to equipment parameters1Connecting any one resistance detection loop of the conversion module to a zero line of a corresponding grounding loop for resistance value detection;
step 2, detecting the resistance value of the corresponding grounding loop to be R for the first time 11If R1-R11|≤10％R1Then proceed to step 3 if | R1-R11|≥10％R1Then go to step 4;
step 3, detecting the resistance value of the corresponding grounding loop every few days, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy | R19-R11|≤10％R1If yes, the initial value is endowed to the corresponding grounding loop again, and the step 2 is repeated;
step 4, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy | R19-R11|≥10％R1Then go to step 5;
step 6, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfies 10% R1＜R1-R11≤35％R1If so, the secondary grounding monitoring device of the transformer substation alarms in a first alarm mode;
7, detecting the resistance value of the corresponding ground circuit every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding ground circuit is detected to the ninth time 19Satisfies 10% R1＜R11-R1≤35％R1If so, the secondary grounding monitoring device of the transformer substation alarms in a third alarm mode;
step 8, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy R1-R11＞35％R1Then the secondary connection of the transformer substationThe ground monitoring device alarms in a second alarm mode;
step 9, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy R11-R1＞35％R1And the secondary grounding monitoring device of the transformer substation alarms in a fourth alarm mode.
Moreover, the fault indicated by the first alarm mode in step 6 includes a secondary resistance reduction due to corrosion of the cable; the fault indicated by the third alarm mode in the step 7 comprises loose grounding points; the fault pointed out by the second alarm mode in the step 8 comprises a cable crust breaking or PT secondary circuit zinc oxide breakdown, so that a second grounding point exists; the fault indicated by the fourth alarm mode in step 9 comprises a virtual ground connection.
The invention has the advantages and positive effects that:
according to the invention, the resistance value of the grounding loop is endowed with an initial value according to the parameters of the grounding loop, the resistance value of the corresponding grounding loop is detected in real time, the resistance value of the corresponding grounding loop detected in real time is compared with the resistance value of the corresponding grounding loop and endowed with the initial value, the operation is repeated for 9 times, and the alarm of different modes is carried out according to the difference, so that the automatic real-time monitoring of the secondary grounding condition of the transformer substation is realized, the fault problem under the alarm of different modes is provided for the working personnel, and the quick fault solving and the operation and maintenance of the transformer.
Drawings
FIG. 1 is a block diagram of the apparatus of the present invention;
fig. 2 is a flow chart of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
A transformer substation secondary grounding monitoring device is shown in figure 1 and comprises a direct resistance testing module, a control module, a conversion module and an alarm display module which are sequentially connected.
The direct resistance testing module uses a direct current resistance tester HPS2511, the control module uses a raspberry group 4BRaspberry, the conversion module uses a programmable relay module YYS-2, the alarm display module uses a scratch display screen and has four alarm modes, the control module raspberry group 4BRaspberry controls the conversion module programmable relay module YYS-2 to connect different resistance detection wires and analyze data collected by the direct current resistance tester HPS2511 and judge whether to alarm, and the direct resistance testing module direct current resistance tester HPS2511 collects the resistance value of a grounding circuit of the connected resistance detection wires.
The conversion module outputs 6 resistance detection wires, the 6 resistance detection wires are respectively connected with a zero line N interface of a current transformer or a voltage transformer field terminal bar, and the transformer substation secondary grounding monitoring device can monitor 6 grounding loop resistance values at the same time.
And after the resistance detection wire is connected with a zero line N interface of the field terminal block, the secondary grounding monitoring device of the transformer substation is placed in a protection screen cabinet, a field terminal box or a control cubicle.
A monitoring method of a secondary grounding monitoring device of a transformer substation, as shown in fig. 2, includes the following steps:
step 1, giving an initial value R to a corresponding grounding loop according to equipment parameters1Connecting any one resistance detection loop of the conversion module to a zero line of a corresponding grounding loop for resistance value detection;
step 2, detecting the resistance value of the corresponding grounding loop to be R for the first time11If R1-R11|≤10％R1Then proceed to step 3 if | R1-R11|≥10％R1Then go to step 4;
step 3, detecting the resistance value of the corresponding grounding loop every 7 days, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy | R19-R11|≤10％R1If yes, the initial value is endowed to the corresponding grounding loop again, and the step 2 is repeated;
step 4, detecting the resistance value of the corresponding grounding loop every 3 hours, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy | R19-R11|≥10％R1Then go to step 5;
step 6, detecting the resistance value of the corresponding grounding loop every 3 hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfies 10% R1＜R1-R11≤35％R1The transformer substation secondary grounding monitoring device alarms in a first alarm mode, wherein the fault indicated in the first alarm mode comprises the reduction of secondary resistance caused by cable corrosion;
7, detecting the resistance value of the corresponding ground circuit every 3 hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding ground circuit is detected to the ninth time19Satisfies 10% R1＜R11-R1≤35％R1If the fault is not detected, the secondary grounding monitoring device of the transformer substation alarms in a second alarm mode, wherein the fault indicated by the second alarm mode comprises that the grounding point is not loosened;
step 8, detecting the resistance value of the corresponding grounding loop every 3 hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy R1-R11＞35％R1If the fault pointed out by the second alarm mode comprises cable sheath breaking or PT secondary circuit zinc oxide breakdown, a second grounding point exists;
Step 9, detecting the resistance value of the corresponding grounding loop every 3 hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy R11-R1＞35％R1And the secondary grounding monitoring device of the transformer substation alarms in a fourth alarm mode, wherein the fault pointed out by the fourth alarm mode comprises the virtual grounding point.
By the transformer substation secondary grounding monitoring device and the transformer substation secondary grounding monitoring method, automatic real-time monitoring of the transformer substation secondary grounding condition is achieved, the fault problem under different mode alarming can be provided for workers, and the quick fault solving and operation and maintenance of the transformer substation are facilitated for the workers.
It should be emphasized that the embodiments described herein are illustrative rather than restrictive, and thus the present invention is not limited to the embodiments described in the detailed description, but also includes other embodiments that can be derived from the technical solutions of the present invention by those skilled in the art.
Claims (6)
1. The utility model provides a transformer substation's secondary ground monitoring device which characterized in that: the device comprises a direct resistance testing module, a control module, a conversion module and an alarm display module which are connected in sequence.
2. The substation secondary grounding monitoring device of claim 1, wherein: the direct resistance testing module uses a direct current resistance tester, the control module uses a raspberry pi, and the conversion module uses a programmable relay.
3. The substation secondary grounding monitoring device of claim 1, wherein: the alarm display module has four alarm modes.
4. The substation secondary grounding monitoring device of claim 1, wherein: the conversion module outputs resistance detection wires with different numbers, and the resistance detection wires are connected with zero lines of a current transformer or a voltage transformer.
5. A monitoring method of a substation secondary grounding monitoring device according to claim 1, characterized by comprising the steps of:
step 1, giving an initial value R to a corresponding grounding loop according to equipment parameters1Connecting any one resistance detection loop of the conversion module to a zero line of a corresponding grounding loop for resistance value detection;
step 2, detecting the resistance value of the corresponding grounding loop to be R for the first time11If R1-R11|≤10％R1Then proceed to step 3 if | R1-R11|≥10％R1Then go to step 4;
step 3, detecting the resistance value of the corresponding grounding loop every few days, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy | R19-R11|≤10％R1If yes, the initial value is endowed to the corresponding grounding loop again, and the step 2 is repeated;
step 4, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 2, and if the resistance value R of the corresponding grounding loop is detected to the ninth time 19Satisfy | R19-R11|≥10％R1Then go to step 5;
step 5, the same initial value R in the step one is endowed to the corresponding grounding loop again1Re-detecting, detecting for the first time that the resistance of the corresponding ground circuit is R11If 10% R1＜R1-R11≤35％R1Then go to step 6 if 10% R1＜R11-R1≤35％R1Then go to step 7, if R1-R11＞35％R1Then go to step 8, if R11-R1＞35％R1Then go to step 9;
step 6, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfies 10% R1＜R1-R11≤35％R1If so, the secondary grounding monitoring device of the transformer substation alarms in a first alarm mode;
step 7, every few hours forDetecting the resistance value of the corresponding grounding loop, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfies 10% R1＜R11-R1≤35％R1If so, the secondary grounding monitoring device of the transformer substation alarms in a third alarm mode;
step 8, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time19Satisfy R1-R11＞35％R1If so, the secondary grounding monitoring device of the transformer substation alarms in a second alarm mode;
step 9, detecting the resistance value of the corresponding grounding loop every several hours, repeating the judgment of the step 5, and if the resistance value R of the corresponding grounding loop is detected to the ninth time 19Satisfy R11-R1＞35％R1And the secondary grounding monitoring device of the transformer substation alarms in a fourth alarm mode.
6. The monitoring method of the substation secondary grounding monitoring device according to claim 5, characterized in that: the fault indicated by the first alarm mode in the step 6 comprises secondary resistance reduction caused by cable corrosion; the fault indicated by the third alarm mode in the step 7 comprises loose grounding points; the fault pointed out by the second alarm mode in the step 8 comprises a cable crust breaking or PT secondary circuit zinc oxide breakdown, so that a second grounding point exists; the fault indicated by the fourth alarm mode in step 9 comprises a virtual ground connection.
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| CN202010587041.0A CN111856179A (en) | 2020-06-24 | 2020-06-24 | Transformer substation secondary grounding monitoring device and method |
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Citations (6)
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|---|---|---|---|---|
| JP2000009786A (en) * | 1998-06-19 | 2000-01-14 | Miwa Electric Co Ltd | Ground fault detection method for secondary power cable of main transformer |
| CN102129005A (en) * | 2011-01-30 | 2011-07-20 | 重庆元虎科技有限公司 | Transformer substation/power plant secondary circuit direct-current ground indicator and application thereof |
| CN202663201U (en) * | 2012-07-30 | 2013-01-09 | 广东汇盈电力工程有限公司 | 110 kilovolt (KV) step-type power transformation monitoring system |
| CN104678261A (en) * | 2015-03-26 | 2015-06-03 | 重庆大学 | Device and method for detecting corrosion state of grounding grid |
| CN109596934A (en) * | 2018-11-30 | 2019-04-09 | 广州格兴全电力科技有限公司 | A kind of double split-core type meter mensurations of secondary circuit multipoint earthing |
| CN210665883U (en) * | 2019-05-10 | 2020-06-02 | 国网湖北省电力有限公司孝感供电公司 | Remote monitoring and fault early warning device for transformer substation grounding system |
-
2020
- 2020-06-24 CN CN202010587041.0A patent/CN111856179A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000009786A (en) * | 1998-06-19 | 2000-01-14 | Miwa Electric Co Ltd | Ground fault detection method for secondary power cable of main transformer |
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| CN202663201U (en) * | 2012-07-30 | 2013-01-09 | 广东汇盈电力工程有限公司 | 110 kilovolt (KV) step-type power transformation monitoring system |
| CN104678261A (en) * | 2015-03-26 | 2015-06-03 | 重庆大学 | Device and method for detecting corrosion state of grounding grid |
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