CN109375117A - A kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method - Google Patents
A kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method Download PDFInfo
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- CN109375117A CN109375117A CN201810857163.XA CN201810857163A CN109375117A CN 109375117 A CN109375117 A CN 109375117A CN 201810857163 A CN201810857163 A CN 201810857163A CN 109375117 A CN109375117 A CN 109375117A
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- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000009413 insulation Methods 0.000 title claims abstract description 30
- 238000007689 inspection Methods 0.000 title claims abstract description 14
- 238000012545 processing Methods 0.000 claims abstract description 23
- 238000004891 communication Methods 0.000 claims abstract description 13
- 238000006243 chemical reaction Methods 0.000 claims abstract description 5
- 238000003708 edge detection Methods 0.000 claims description 7
- 238000004458 analytical method Methods 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims description 3
- 238000012937 correction Methods 0.000 claims description 3
- 239000004973 liquid crystal related substance Substances 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- 230000004044 response Effects 0.000 claims description 3
- 239000000523 sample Substances 0.000 claims description 3
- 238000012360 testing method Methods 0.000 claims description 3
- 230000005611 electricity Effects 0.000 claims description 2
- 230000010354 integration Effects 0.000 claims description 2
- 238000005070 sampling Methods 0.000 claims 1
- 230000009466 transformation Effects 0.000 claims 1
- 238000012544 monitoring process Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 2
- 230000006837 decompression Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005404 monopole Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
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
- G01R31/40—Testing power supplies
-
- 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
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- General Physics & Mathematics (AREA)
- Emergency Protection Circuit Devices (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The present invention provides a kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method, the Insulation Inspection System includes signal acquisition unit, signal processing unit, A/D converting unit, central control unit, relay, storage unit, display unit, alarm unit, communication unit and key-press input unit；Signal acquisition unit handles the signal input signal processing unit of acquisition, A/D converting unit is inputted again to carry out A/D conversion and input central control unit, central control unit is compared judgement with preset reference value to the signal of input, detect the integrated power supply insulation status, and storage is carried out by storage unit and display unit and is shown, if there is insulation fault, classification alarm is carried out by alarm unit.The present invention provides a kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method, provides effective guarantee for the normal operation of direct current system safety.
Description
Technical field
The invention belongs to technical field of electric power detection, in particular to a kind of intelligence based on bridge method and DC leakage current method
Substation's integrated power supply Insulation Inspection System.
Background technique
With the continuous development of power technology, intelligent substation is commonplace, compared to more traditional direct current supply system
System is powered using integrated power source apparatus now: DC power supply, electric power inverter, leads to electric power ac uninterrupted power supply
The devices such as credit DC transformating power are combined into one, and share the battery group of DC power supply, and are uniformly monitored complete
Equipment.
Insulation monitoring is one of most important guarantee in integrated power supply management, and a perfect power-supply management system is not from
Open good Insulation monitoring function.Insulation fault once occurs for integrated power supply, and it is straight that problem often occurs from its main part
It flows in power-supply system.When monopole ground connection occurs for direct current system, it cannot be formed into a loop, because without generating short circuit current.But such as
Fruit is not handled in time, when two points ground fault or multipoint earthing occurs in system, it is possible to ground short circuit failure is constituted, from
And cause protective relaying device, automation equipment and device for signalling that malfunction tripping occurs, DC insurance fusing is even resulted in,
Direct current system decompression.Therefore it provides a set of effective integrated power supply Insulation Inspection System is the normal fortune of direct current system safety
Row provides effective ensure.
Summary of the invention
The present invention provides a kind of intelligent substation integrated power supply Insulation monitoring based on bridge method and DC leakage current method
System provides effective guarantee for the normal operation of direct current system safety.
The present invention is specially that a kind of insulated based on the intelligent substation integrated power supply of bridge method and DC leakage current method is examined
Examining system, the Insulation Inspection System include signal acquisition unit, signal processing unit, A/D converting unit, center control list
Member, relay, storage unit, display unit, alarm unit, communication unit and key-press input unit, the signal acquisition unit,
The signal processing unit, the A/D converting unit and the central control unit are linked in sequence, the central control unit point
Not with the signal acquisition unit, the signal processing unit, the relay, the storage unit, the display unit, institute
State alarm unit, the communication unit is connected with the key-press input unit, the relay also with the signal acquisition list
Member is connected；The signal of acquisition is inputted the signal processing unit and is filtered enhanced processing by the signal acquisition unit, then
It inputs the A/D converting unit to carry out A/D conversion and input the central control unit, the central control unit is to input
Signal is compared judgement with preset reference value, detects the integrated power supply insulation status, and pass through the storage
Unit and the display unit carry out storage and show, if there is insulation fault, carry out classification alarm by the alarm unit.
The signal acquisition unit acquisition DC bus positive and negative electrode voltage-to-ground and branch leakage current, the DC bus
Positive and negative electrode voltage-to-ground is measured using partial pressure method, and the DC bus positive and negative electrode is directly accessed voltage with conducting wire and accesses circuit
Interior, the voltage access circuit is by balance resistance bridge joint ground, and the central control unit is by controlling closing for the relay
It closes and disconnects, and then control the state that ground resistance accesses tested branch；The branch leakage current is sensed using DC leakage current
Device acquires the out-of-balance current of branch road, and the branch positive and negative electrode cable is all passed through from the DC leakage current center sensor,
Electrical link does not occur；The branch number be more than or equal to 1, the DC leakage current number of probes also greater than be equal to 1, and with
The branch number is equal.
The signal processing unit includes difference amplifier, low-pass filter, and input signal is amplified and filtered respectively
Wave processing.
The display unit uses liquid crystal display, in conjunction with the storage unit, the key-press input unit to the intelligence
It can substation's integrated power supply progress parameter setting；The display unit can real-time display DC bus positive and negative electrode it is electric over the ground
Pressure value, branch leakage current value and failure report.
The relay includes the first relay and the second relay, and first relay is alternate with DC bus anode
It connects, second relay and DC bus cathode are mutually indirect, and the central control unit carries out circulation behaviour to the relay
Make, share three steps:
Step 1 is closed first relay, is closed second relay；
Step 2 is closed first relay, disconnects second relay；
Step 3 disconnects first relay, is closed second relay；
It is separated by 10 power frequency periods between each step.
The central control unit controls the signal acquisition unit according to preset relevant parameter, at the signal
The acquisition process work for managing unit, relay progress signal, according to the DC bus positive and negative electrode voltage-to-ground of acquisition
Value and the branch leakage current value judge whether that ground fault and fault type occurs:
If the branch leakage current value is not zero, the DC bus positive and negative electrode voltage-to-ground value is reduced, then the intelligence
Monopolar grounding fault occurs for substation's integrated power supply；
If the branch leakage current value is zero, the DC bus positive and negative electrode voltage-to-ground value is constant, respectively according to
It is adopted when first relay closure, second relay disconnect and first relay disconnects, second relay is closed
The DC bus positive and negative electrode voltage-to-ground value of collection calculates the two poles of the earth insulation against ground resistance value using Kirchhoff's law, into
And judge whether that two pole ground faults occur；
The central control unit carries out Difference Calculation to the DC bus positive and negative electrode voltage-to-ground value of acquisition, sentences
Break whether to occur to exchange and scurry into DC Line Fault,The UACHave to scurry into the alternating current of direct current system
Valid value, the A are correction coefficient, the u1…unFor collected voltage in each period, the n is adopting in signal period
Number of samples.
The communication unit uses MODBUS communications protocol to be communicated with master-slave mode, the Insulation Inspection System conduct
The command response that slave is sent according to host computer, and will test data and the analysis result upload host computer.
Detailed description of the invention
Fig. 1 is a kind of intelligent substation integrated power supply Insulation monitoring based on bridge method and DC leakage current method of the present invention
The structural schematic diagram of system.
Specific embodiment
It is a kind of to the present invention based on the intelligent substation of bridge method and DC leakage current method integration electricity with reference to the accompanying drawing
The specific embodiment of source Insulation Inspection System elaborates.
As shown in Figure 1, Insulation Inspection System of the invention includes signal acquisition unit, signal processing unit, A/D conversion list
Member, central control unit, relay, storage unit, display unit, alarm unit, communication unit and key-press input unit, it is described
Signal acquisition unit, the signal processing unit, the A/D converting unit and the central control unit are linked in sequence, described
Central control unit respectively with the signal acquisition unit, the signal processing unit, the relay, the storage unit,
The display unit, the alarm unit, the communication unit are connected with the key-press input unit, the relay also with
The signal acquisition unit is connected；The signal of acquisition is inputted the signal processing unit and filtered by the signal acquisition unit
Wave enhanced processing, then input the A/D converting unit and carry out A/D conversion and input the central control unit, the center control
Unit processed is compared judgement with preset reference value to the signal of input, detects the integrated power supply insulation status,
And storage is carried out by the storage unit and the display unit and is shown, if there is insulation fault, pass through the alarm unit
Carry out classification alarm.
The signal acquisition unit acquisition DC bus positive and negative electrode voltage-to-ground and branch leakage current, the DC bus
Positive and negative electrode voltage-to-ground is measured using partial pressure method, and the DC bus positive and negative electrode is directly accessed voltage with conducting wire and accesses circuit
Interior, the voltage access circuit is by balance resistance bridge joint ground, and the central control unit is by controlling closing for the relay
It closes and disconnects, and then control the state that ground resistance accesses tested branch；The branch leakage current is sensed using DC leakage current
Device acquires the out-of-balance current of branch road, and the branch positive and negative electrode cable is all passed through from the DC leakage current center sensor,
Electrical link does not occur；The branch number be more than or equal to 1, the DC leakage current number of probes also greater than be equal to 1, and with
The branch number is equal.
The signal processing unit includes difference amplifier, low-pass filter, and input signal is amplified and filtered respectively
Wave processing.
The display unit uses liquid crystal display, in conjunction with the storage unit, the key-press input unit to the intelligence
It can substation's integrated power supply progress parameter setting；The display unit can real-time display DC bus positive and negative electrode it is electric over the ground
Pressure value, branch leakage current value and failure report.
The relay includes the first relay and the second relay, and first relay is alternate with DC bus anode
It connects, second relay and DC bus cathode are mutually indirect, and the central control unit carries out circulation behaviour to the relay
Make, share three steps:
Step 1 is closed first relay, is closed second relay；
Step 2 is closed first relay, disconnects second relay；
Step 3 disconnects first relay, is closed second relay；
It is separated by 10 power frequency periods between each step.
The central control unit controls the signal acquisition unit according to preset relevant parameter, at the signal
The acquisition process work for managing unit, relay progress signal, according to the DC bus positive and negative electrode voltage-to-ground of acquisition
Value and the branch leakage current value judge whether that ground fault and fault type occurs:
If the branch leakage current value is not zero, the DC bus positive and negative electrode voltage-to-ground value is reduced, then the intelligence
Monopolar grounding fault occurs for substation's integrated power supply；
If the branch leakage current value is zero, the DC bus positive and negative electrode voltage-to-ground value is constant, respectively according to
It is adopted when first relay closure, second relay disconnect and first relay disconnects, second relay is closed
The DC bus positive and negative electrode voltage-to-ground value of collection calculates the two poles of the earth insulation against ground resistance value using Kirchhoff's law, into
And judge whether that two pole ground faults occur；
The central control unit carries out Difference Calculation to the DC bus positive and negative electrode voltage-to-ground value of acquisition, sentences
Break whether to occur to exchange and scurry into DC Line Fault,The UACHave to scurry into the alternating current of direct current system
Valid value, the A are correction coefficient, the u1...unFor collected voltage in each period, the n is adopting in signal period
Number of samples.
The communication unit uses MODBUS communications protocol to be communicated with master-slave mode, the Insulation Inspection System conduct
The command response that slave is sent according to host computer, and will test data and the analysis result upload host computer.
Finally it should be noted that only illustrating technical solution of the present invention rather than its limitations in conjunction with above-described embodiment.Institute
The those of ordinary skill in category field is it is to be understood that those skilled in the art can repair a specific embodiment of the invention
Change or equivalent replacement, but these modifications or change are being applied among pending claims.
Claims (7)
1. a kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method, feature exist
In, the Insulation Inspection System include signal acquisition unit, signal processing unit, A/D converting unit, central control unit, after
Electric appliance, storage unit, display unit, alarm unit, communication unit and key-press input unit, it is the signal acquisition unit, described
Signal processing unit, the A/D converting unit and the central control unit are linked in sequence, the central control unit respectively with
The signal acquisition unit, the signal processing unit, the relay, the storage unit, the display unit, the report
Alert unit, the communication unit are connected with the key-press input unit, the relay also with the signal acquisition unit phase
Connection；The signal of acquisition is inputted the signal processing unit and is filtered enhanced processing by the signal acquisition unit, then is inputted
The A/D converting unit carries out A/D conversion and inputs the central control unit, signal of the central control unit to input
It is compared judgement with preset reference value, detects the integrated power supply insulation status, and pass through the storage unit
Storage is carried out with the display unit to show, if there is insulation fault, classification alarm is carried out by the alarm unit.
2. a kind of intelligent substation integrated power supply based on bridge method and DC leakage current method according to claim 1 is exhausted
Edge detection system, which is characterized in that the signal acquisition unit acquisition DC bus positive and negative electrode voltage-to-ground and branch electric leakage
Stream, the DC bus positive and negative electrode voltage-to-ground are measured using partial pressure method, and the DC bus positive and negative electrode is directly connect with conducting wire
Enter in voltage access circuit, the voltage access circuit passes through control by balance resistance bridge joint ground, the central control unit
The open and close of the relay, and then control the state that ground resistance accesses tested branch；The branch leakage current uses
DC leakage flow sensor acquires the out-of-balance current of branch road, and the branch positive and negative electrode cable is all from the DC leakage current
Center sensor passes through, and electrical link does not occur；The branch number is more than or equal to 1, the DC leakage current number of probes
It is and equal with the branch number also greater than being equal to 1.
3. a kind of intelligent substation integrated power supply based on bridge method and DC leakage current method according to claim 1 is exhausted
Edge detection system, which is characterized in that the signal processing unit includes difference amplifier, low-pass filter, is believed respectively input
It number amplifies and is filtered.
4. a kind of intelligent substation integrated power supply based on bridge method and DC leakage current method according to claim 1 is exhausted
Edge detection system, which is characterized in that the display unit uses liquid crystal display, defeated in conjunction with the storage unit, the key
Enter unit and parameter setting is carried out to the intelligent substation integrated power supply；The display unit being capable of real-time display DC bus
Positive and negative electrode voltage-to-ground value, branch leakage current value and failure report.
5. according to claim 1 or 2 a kind of based on the intelligent substation of bridge method and DC leakage current method integration electricity
Source Insulation Inspection System, which is characterized in that the relay includes the first relay and the second relay, first relay
Mutually indirect with DC bus anode, second relay and DC bus cathode are mutually indirect, and the central control unit is to institute
It states relay and carries out circulate operation, share three steps:
Step 1 is closed first relay, is closed second relay；
Step 2 is closed first relay, disconnects second relay；
Step 3 disconnects first relay, is closed second relay；
It is separated by 10 power frequency periods between each step.
6. a kind of intelligent substation integrated power supply based on bridge method and DC leakage current method according to claim 5 is exhausted
Edge detection system, which is characterized in that the central control unit controls the signal acquisition according to preset relevant parameter
Unit, the signal processing unit, the relay carry out the acquisition process work of signal, according to the DC bus of acquisition
Positive and negative electrode voltage-to-ground value and the branch leakage current value judge whether that ground fault and fault type occurs:
If the branch leakage current value is not zero, the DC bus positive and negative electrode voltage-to-ground value is reduced, then the intelligent power transformation
Monopolar grounding fault occurs for integrated power supply of standing；
If the branch leakage current value is zero, the DC bus positive and negative electrode voltage-to-ground value is constant, respectively according to described first
It is acquired when relay closure, second relay disconnect and first relay disconnects, second relay is closed
The DC bus positive and negative electrode voltage-to-ground value calculates the two poles of the earth insulation against ground resistance value using Kirchhoff's law, and then sentences
It is disconnected that two pole ground faults whether occur；
The central control unit carries out Difference Calculation to the DC bus positive and negative electrode voltage-to-ground value of acquisition, and judgement is
DC Line Fault is scurried into no generation exchange,UACFor the effective value of alternating current for scurrying into direct current system, A is
Correction coefficient, u1…unFor collected voltage in each period, n is the sampling number in signal period.
7. a kind of intelligent substation integrated power supply based on bridge method and DC leakage current method according to claim 1 is exhausted
Edge detection system, which is characterized in that the communication unit uses MODBUS communications protocol to be communicated with master-slave mode, described exhausted
The command response that edge detection system is sent as slave according to host computer, and will test data and analysis result upload it is described upper
Machine.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810857163.XA CN109375117A (en) | 2018-07-31 | 2018-07-31 | A kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method |
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| CN201810857163.XA CN109375117A (en) | 2018-07-31 | 2018-07-31 | A kind of intelligent substation integrated power supply Insulation Inspection System based on bridge method and DC leakage current method |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110579697A (en) * | 2019-10-25 | 2019-12-17 | 国网江苏省电力有限公司盐城供电分公司 | Multifunctional insulation detection device based on direct current system and detection method thereof |
| CN110596519A (en) * | 2019-10-18 | 2019-12-20 | 国网江苏省电力有限公司盐城供电分公司 | Direct current system ground fault detection system based on Fourier transform and detection method thereof |
| CN115084592A (en) * | 2022-06-07 | 2022-09-20 | 武汉氢能与燃料电池产业技术研究院有限公司 | Online insulation resistance detection system and method for fuel cell |
| CN116908644A (en) * | 2023-06-09 | 2023-10-20 | 国网山东省电力公司金乡县供电公司 | Device and method for testing direct current circuit of transformer substation |
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| CN103675613A (en) * | 2013-11-01 | 2014-03-26 | 国家电网公司 | Transformer station DC system movable type insulation supervision instrument |
| CN204705694U (en) * | 2015-06-18 | 2015-10-14 | 江苏安科瑞电器制造有限公司 | Photovoltaic DC insulation monitoring and warning device |
| CN106556778A (en) * | 2015-09-25 | 2017-04-05 | 浙江科畅电子有限公司 | A kind of Insulation Inspection Device for Direct-Current System |
| CN208270709U (en) * | 2018-07-03 | 2018-12-21 | 国网江苏省电力有限公司徐州供电分公司 | A kind of intelligent substation integrated power supply Insulation Inspection System |
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| CN103675613A (en) * | 2013-11-01 | 2014-03-26 | 国家电网公司 | Transformer station DC system movable type insulation supervision instrument |
| CN204705694U (en) * | 2015-06-18 | 2015-10-14 | 江苏安科瑞电器制造有限公司 | Photovoltaic DC insulation monitoring and warning device |
| CN106556778A (en) * | 2015-09-25 | 2017-04-05 | 浙江科畅电子有限公司 | A kind of Insulation Inspection Device for Direct-Current System |
| CN208270709U (en) * | 2018-07-03 | 2018-12-21 | 国网江苏省电力有限公司徐州供电分公司 | A kind of intelligent substation integrated power supply Insulation Inspection System |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110596519A (en) * | 2019-10-18 | 2019-12-20 | 国网江苏省电力有限公司盐城供电分公司 | Direct current system ground fault detection system based on Fourier transform and detection method thereof |
| CN110579697A (en) * | 2019-10-25 | 2019-12-17 | 国网江苏省电力有限公司盐城供电分公司 | Multifunctional insulation detection device based on direct current system and detection method thereof |
| CN115084592A (en) * | 2022-06-07 | 2022-09-20 | 武汉氢能与燃料电池产业技术研究院有限公司 | Online insulation resistance detection system and method for fuel cell |
| CN116908644A (en) * | 2023-06-09 | 2023-10-20 | 国网山东省电力公司金乡县供电公司 | Device and method for testing direct current circuit of transformer substation |
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Application publication date: 20190222 |