CN104410045B - The isolating transformer differential protective system and method for a kind of photoelectricity CT mixing - Google Patents
The isolating transformer differential protective system and method for a kind of photoelectricity CT mixing Download PDFInfo
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- CN104410045B CN104410045B CN201410741298.1A CN201410741298A CN104410045B CN 104410045 B CN104410045 B CN 104410045B CN 201410741298 A CN201410741298 A CN 201410741298A CN 104410045 B CN104410045 B CN 104410045B
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Abstract
The present invention provides the isolating transformer differential protective system and method for a kind of photoelectricity CT mixing, and system includes side unit, isolating transformer, secondary side unit, secondary protection system, system inlet wire, system outlet and breaker；System inlet wire and system outlet are connected to the primary and secondary side of isolating transformer by a side unit and secondary side unit respectively; side unit and secondary side unit are connected with secondary protection system, and the breaker is located between system inlet wire and a side unit.The present invention provides the isolating transformer differential protective system and method for a kind of photoelectricity CT mixing; system architecture is compact, strong antijamming capability, reliability high; it can accurately judge that the excitation surge current of transformer carrys out retaining differential protection, application covers all transformer differential protection systems.
Description
Technical field
The present invention relates to belong to tranformer protection technical field, and in particular to a kind of isolating transformer of photoelectricity CT mixing is poor
Dynamic protection system and method.
Background technology
With continuing to develop for power system, the application of high-power transformer is increasingly extensive, to the reliability of tranformer protection
Property with quick-action propose higher requirement, transformer differential protection is received general due to its good selectivity and rapidity
All over attention.Differential protection is widely used in traditional analog protection as the key technology of power transformer relay protection
In new-type Microcomputer Protection.Long-term operating experience shows, in the subject matter of current transformer differential protection is still concentrated on
In the discriminating of portion's failure and excitation surge current.When there is excitation surge current, protection must refuse tripping operation；And internal fault current is sent out
Raw, protection must fast trip.Existing braking magnetizing inrush current principle is mainly secondary harmonic brake and interval angle braking.These
Theory has some limitations, differentiates that power transformer excitation surge current and internal fault current are not accurate enough.
Secondary harmonic brake is to utilize the characteristics of containing second harmonic in excitation surge current, designs the side of secondary harmonic brake
Method, once protection detect it is differential in the second harmonic that contains be more than protection seting value, with regard to latch-up protection, prevent that excitation surge current from drawing
Play false protection.But, during high-power transformer internal fault, the second harmonic component in short circuit current flow is substantially increased due to resonance
Plus, this may cause the deferred action or tripping of differential protection.During in the event of excitation surge current, second harmonic component is less than normal
When, differential protection malfunction can be caused again.
Interval angle braking principle is a kind of recognition methods of the wave character according to excitation surge current, and inrush has larger
The angle of rupture, excitation surge current is judged by detecting difference stream interval angle size.Interval angle is braked as interruption angular deformation causes difference
Dynamic false protection.
Accordingly, it would be desirable to which a kind of new method recognizes excitation surge current, so as to finally solve the excitation of transformer differential protection
Shove braking the problem of.
The content of the invention
In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a kind of differential guarantor of isolating transformer of photoelectricity CT mixing
Protecting system and method, system architecture is compact, strong antijamming capability, reliability high, can accurately judge that the excitation of transformer is gushed
Stream carrys out retaining differential protection, and application covers all transformer differential protection systems.
In order to realize foregoing invention purpose, the present invention is adopted the following technical scheme that：
The present invention provides a kind of isolating transformer differential protective system of photoelectricity CT mixing, and the system includes primary side list
Member, isolating transformer, secondary side unit, secondary protection system, system inlet wire, system outlet and breaker；System inlet wire and it is
System outlet is connected to the primary and secondary side of isolating transformer, the primary side list by a side unit and secondary side unit respectively
First and secondary side unit is connected with secondary protection system, and the breaker is located between system inlet wire and a side unit.
Side unit includes the first all-fiber current transformator OCT1 and the first electromagnetic current transducer CT1；
The first all-fiber current transformator OCT1 is used to measure electrical equipment electric current, and the primary side of isolating transformer is wound on by optical fiber
On inlet wire, the primary side inlet wire of isolating transformer is passed through after the first all-fiber current transformator OCT1, is worn by copper bar or cable
The first electromagnetic current transducer CT1 is crossed, the primary side of isolating transformer is entered back into.
The secondary side unit includes the second electromagnetic current transducer CT2；The secondary outlet of the isolating transformer is led to
Cross copper bar or cable passes through the second electromagnetic current transducer CT2, reconnect system outlet；
The first all-fiber current transformator OCT1 is connected by optical fiber with secondary protection system, the first electromagnetic type electricity
Current transformer CT1 and the second electromagnetic current transducer CT2 are connected by secondary cable with secondary protection system.
It is logical that the secondary side unit includes the second all-fiber current transformator OCT2, the second all-fiber current transformator OCT2
Cross optical fiber to be wound in the secondary outlet of isolating transformer, the secondary outlet of isolating transformer passes through the second all-fiber current transformator
After OCT2, connection system outlet；
The first all-fiber current transformator OCT1 and the second all-fiber current transformator OCT2 pass through optical fiber and two
Secondary protection system is connected, and the first electromagnetic current transducer CT1 is connected by secondary cable with secondary protection system.
The secondary side unit includes the second all-fiber current transformator OCT2 and the second electromagnetic current transducer CT2；
Second all-fiber current transformator OCT2 is used to measure electrical equipment electric current, and the secondary outlet of isolating transformer is wound on by optical fiber
On, the secondary outlet of isolating transformer is passed through after the second all-fiber current transformator OCT2, by copper bar or cable through the
After two electromagnetic current transducer CT2, connection system outlet；
The second all-fiber current transformator OCT2 of the first all-fiber current transformator OCT1 and secondary side unit are equal
It is connected by optical fiber with secondary protection system, the second electromagnetic type of the first electromagnetic current transducer CT1 and secondary side unit
Current Transmit 2 is connected by secondary cable with secondary protection system.
The secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop and protection processing
Unit；
First treatment loop is all-fiber current transformator treatment loop, and it includes optical signal detector, A/D conversions
Device and OCT processing units；
The optical signal detector of first treatment loop receives the fiber-optic signal from a side unit, and optical fiber is believed
Voltage signal number is converted to, voltage signal is converted to data signal by A/D converter, and it is single that data signal is sent to OCT processing
Member, OCT processing units do calibration processing to data signal, and according to temperature influence and measurement range, the OCT1 most measured at last
Current signal is sent to protection processing unit by communication interface；
The second processing loop and the 3rd treatment loop are electromagnetic current transducer treatment loop, electromagnetic type electric current
Transformer treatment loop includes current sensor, A/D converter and CT processing units；
The current sensor of the second processing loop and the 3rd treatment loop is received from a side unit and two respectively
The cable signal of secondary side unit, voltage signal is converted to by current sensor, and voltage signal is converted to number by A/D converter
Word signal, data signal is sent to CT processing units, and CT processing units do calibration processing to data signal, most measured at last
CT1 current signals and CT2 current signals are sent to protection processing unit by communication interface；
The protection processing unit receives OCT1 current signals, CT1 current signals and CT2 current signals, carries out differential protect
Shield processing.
The secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop and protection processing
Unit；
First treatment loop and the 3rd treatment loop are all-fiber current transformator treatment loop, and it includes light letter
Number detector, A/D converter and OCT processing units；
The optical signal detector of first treatment loop and the 3rd treatment loop receive respectively from side unit and
The fiber-optic signal of secondary side unit, and fiber-optic signal is converted into voltage signal, voltage signal is converted to number by A/D converter
Word signal, data signal is sent to OCT processing units, and OCT processing units do calibration processing to data signal, and according to temperature shadow
Ring and measurement range, the OCT1 current signals and OCT2 current signals most measured at last is sent to protection by communication interface and handled
Unit；
The second processing loop is electromagnetic current transducer treatment loop, electromagnetic current transducer treatment loop bag
Include current sensor, A/D converter and CT processing units；
The current sensor in the second processing loop receives the cable signal from a side unit, passes through current sense
Device is converted to voltage signal, and voltage signal is converted to data signal by A/D converter, and it is single that data signal is sent to CT processing
Member, CT processing units do calibration processing to data signal, and the CT1 current signals most measured at last are sent to protection by communication interface
Processing unit；
The protection processing unit receives OCT1 current signals, CT1 current signals and OCT2 current signals, carries out differential protect
Shield processing.
The secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop, fourth process time
Road and protection processing unit；
First treatment loop and the 3rd treatment loop are all-fiber current transformator treatment loop, and it includes light letter
Number detector, A/D converter and OCT processing units；
The optical signal detector of first treatment loop and the 3rd treatment loop, which is received, comes from a side unit and secondary
The fiber-optic signal of side unit, and fiber-optic signal is converted into voltage signal, voltage signal is converted to digital letter by A/D converter
Number, data signal is sent to OCT processing units, and OCT processing units do calibration processing to data signal, and according to temperature influence and
Measurement range, it is single that the OCT1 current signals and OCT2 current signals most measured at last is sent to protection processing by communication interface
Member.
The second processing loop and fourth process loop are electromagnetic current transducer treatment loop, electromagnetic type electric current
Transformer treatment loop includes current sensor, A/D converter and CT processing units；
The current sensor in the second processing loop and fourth process loop is received from a side unit and two respectively
The cable signal of secondary side unit, voltage signal is converted to by current sensor, and voltage signal is converted to number by A/D converter
Word signal, data signal is sent to CT processing units, and CT processing units do calibration processing to data signal, most measured at last
CT1 current signals and CT2 current signals are sent to protection processing unit by communication interface；
The protection processing unit receives OCT1 current signals, OCT2 current signals, CT1 current signals and CT2 electric currents letter
Number, carry out differential protection processing.
The transformer is single-phase transformer, three-phase transformer or auto-transformer.
The present invention also provides a kind of isolating transformer differential protecting method of photoelectricity CT mixing, it is characterised in that：The side
Method comprises the following steps：
Step 1：Carry out the judgement of differential protection；
If flowing through the first electromagnetic current transducer CT1 and the second electromagnetic current transducer CT2 electric current respectively ICT1
And ICT2, ICT1And ICT2Protection difference Δ Icd2Represent, i.e. Δ Icd2=ICT1-ICT2；
If Δ Icd2＞ Ixz, then show that protection difference is out-of-limit, complete the judgement of differential protection, wherein IxzFor protection difference limit
Value；
Step 2：Carry out the judgement of isolating transformer excitation surge current and the judgement of internal fault；
If flowing through the first all-fiber current transformator OCT1 electric currents for IOCT1, IOCT1With ICT1Braking difference Δ Izdc1Table
Show, i.e. Δ Izdc1=IOCT1-ICT1；
If Δ Izdc1＞ Ixz_zd, then show that braking difference is out-of-limit, be determined as that excitation surge current occurs for isolating transformer；Otherwise sentence
It is set to isolating transformer and occurs internal fault, wherein Ixz_zdFor braking difference limit value.
Compared with prior art, the beneficial effects of the present invention are：
1) protection system can accurately identify excitation surge current, so as to thoroughly solve the excitation surge current of transformer differential protection
The problem of braking；
2) protection system can accurately measure the current signal with DC component using light CT；
3) determination methods are simple, easily realize；
4) protection system has wide range of applications, and can be applied to all transformer differential protections.
5) upgrading to original tranformer protection system is simple, only need to increase an all -fiber electricity in isolating transformer primary side
Current transformer, then change secondary protection system.
Brief description of the drawings
Fig. 1 is the isolating transformer differential protective system structure chart of photoelectricity CT mixing；
Fig. 2 is the isolating transformer differential protective system structure chart of photoelectricity CT mixing in the embodiment of the present invention 1；
Fig. 3 is secondary protection system structure chart in the embodiment of the present invention 1；
Fig. 4 is the isolating transformer differential protective system structure chart of photoelectricity CT mixing in the embodiment of the present invention 2；
Fig. 5 is secondary protection system structure chart in the embodiment of the present invention 2；
Fig. 6 is the isolating transformer differential protective system structure chart of photoelectricity CT mixing in the embodiment of the present invention 3；
Fig. 7 is secondary protection system structure chart in the embodiment of the present invention 3.
Embodiment
The present invention is described in further detail below in conjunction with the accompanying drawings.
Embodiment 1
Such as Fig. 1, a kind of isolating transformer differential protective system of photoelectricity CT mixing, the system include side unit,
Isolating transformer, secondary side unit, secondary protection system, system inlet wire, system outlet and breaker；System inlet wire and system go out
Line is connected to the primary and secondary side of isolating transformer by a side unit and secondary side unit respectively, a side unit and
Secondary side unit is connected with secondary protection system, and the breaker is located between system inlet wire and a side unit.
Side unit includes the first all-fiber current transformator OCT1 and the first electromagnetic current transducer CT1；
The first all-fiber current transformator OCT1 is used to measure electrical equipment electric current, and the primary side of isolating transformer is wound on by optical fiber
On inlet wire, the primary side inlet wire of isolating transformer is passed through after the first all-fiber current transformator OCT1, is worn by copper bar or cable
The first electromagnetic current transducer CT1 is crossed, the primary side of isolating transformer is entered back into.
Such as Fig. 2, the secondary side unit includes the second electromagnetic current transducer CT2；The secondary of the isolating transformer
Outlet passes through the second electromagnetic current transducer CT2 by copper bar or cable, reconnects system outlet.
The first all-fiber current transformator OCT1 is connected by optical fiber with secondary protection system, the first electromagnetic type electricity
Second electromagnetic current transducer CT2 of current transformer CT1 and secondary side unit passes through secondary cable and secondary protection system
Connection.
Such as Fig. 3, the secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop and guarantor
Protect processing unit.
First treatment loop is all-fiber current transformator treatment loop, and it includes optical signal detector, A/D conversions
Device and OCT processing units；
The optical signal detector receives the fiber-optic signal from a side unit, and fiber-optic signal is converted into voltage letter
Number, voltage signal is converted to data signal by A/D converter, and data signal is sent to OCT processing units, OCT processing units
Calibration processing is done to data signal, and according to temperature influence and measurement range, the OCT1 current signals most measured at last pass through logical
Communication interface is sent to protection processing unit.
The second processing loop and the 3rd treatment loop are electromagnetic current transducer treatment loop, electromagnetic type electric current
Transformer treatment loop includes current sensor, A/D converter and CT processing units；
The current sensor of the second processing loop and the 3rd treatment loop is received from a side unit and two respectively
The cable signal of secondary side unit, voltage signal is converted to by current sensor, and voltage signal is converted to number by A/D converter
Word signal, data signal is sent to CT processing units, and CT processing units do calibration processing to data signal, most measured at last
CT1 current signals and CT2 current signals are sent to protection processing unit by communication interface；
The protection processing unit receives OCT1 current signals, CT1 current signals and CT2 current signals, carries out differential protect
Shield processing.
The transformer is single-phase transformer, three-phase transformer or auto-transformer.
Embodiment 2
Such as Fig. 4, a kind of isolating transformer differential protective system of photoelectricity CT mixing, the system include side unit,
Isolating transformer, secondary side unit, secondary protection system, system inlet wire, system outlet and breaker；System inlet wire and system go out
Line is connected to the primary and secondary side of isolating transformer by a side unit and secondary side unit respectively, a side unit and
Secondary side unit is connected with secondary protection system, and the breaker is located between system inlet wire and a side unit.
Side unit includes the first all-fiber current transformator OCT1 and the first electromagnetic current transducer CT1；
The first all-fiber current transformator OCT1 is used to measure electrical equipment electric current, and the primary side of isolating transformer is wound on by optical fiber
On inlet wire, the primary side inlet wire of isolating transformer is passed through after the first all-fiber current transformator OCT1, is worn by copper bar or cable
The first electromagnetic current transducer CT1 is crossed, the primary side of isolating transformer is entered back into.
It is logical that the secondary side unit includes the second all-fiber current transformator OCT2, the second all-fiber current transformator OCT2
Cross optical fiber to be wound in the secondary outlet of isolating transformer, the secondary outlet of isolating transformer passes through the second all-fiber current transformator
After OCT2, connection system outlet.
The first all-fiber current transformator OCT1 and the second all-fiber current transformator OCT2 respectively by optical fiber with
Secondary protection system is connected, and the first electromagnetic current transducer CT1 is connected by secondary cable with secondary protection system.
Such as Fig. 5, the secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop and guarantor
Protect processing unit.
First treatment loop and the 3rd treatment loop are all-fiber current transformator treatment loop, and it includes light letter
Number detector, A/D converter and OCT processing units；
The optical signal detector of first treatment loop and the 3rd treatment loop, which is received, comes from a side unit and secondary
The fiber-optic signal of side unit, and fiber-optic signal is converted into voltage signal, voltage signal is converted to digital letter by A/D converter
Number, data signal is sent to OCT processing units, and OCT processing units do calibration processing to data signal, and according to temperature influence and
Measurement range, it is single that the OCT1 current signals and OCT2 current signals most measured at last is sent to protection processing by communication interface
Member.
The second processing loop is electromagnetic current transducer treatment loop, electromagnetic current transducer treatment loop bag
Include current sensor, A/D converter and CT processing units；
The current sensor in the second processing loop receives the cable signal from a side unit, passes through current sense
Device is converted to voltage signal, and voltage signal is converted to data signal by A/D converter, and it is single that data signal is sent to CT processing
Member, CT processing units do calibration processing to data signal, and the CT1 current signals most measured at last are sent to protection by communication interface
Processing unit；
The protection processing unit receives OCT1 current signals, CT1 current signals and OCT2 current signals, carries out differential protect
Shield processing.
The transformer is single-phase transformer, three-phase transformer or auto-transformer.
Embodiment 3
Such as Fig. 6, a kind of isolating transformer differential protective system of photoelectricity CT mixing, the system include side unit,
Isolating transformer, secondary side unit, secondary protection system, system inlet wire, system outlet and breaker；System inlet wire and system go out
Line is connected to the primary and secondary side of isolating transformer by a side unit and secondary side unit respectively, a side unit and
Secondary side unit is connected with secondary protection system, and the breaker is located between system inlet wire and a side unit.
Side unit includes the first all-fiber current transformator OCT1 and the first electromagnetic current transducer CT1；
The first all-fiber current transformator OCT1 is used to measure electrical equipment electric current, and the primary side of isolating transformer is wound on by optical fiber
On inlet wire, the primary side inlet wire of isolating transformer is passed through after the first all-fiber current transformator OCT1, is worn by copper bar or cable
The first electromagnetic current transducer CT1 is crossed, the primary side of isolating transformer is entered back into.
The secondary side unit includes the second all-fiber current transformator OCT2 and the second electromagnetic current transducer CT2；
Second all-fiber current transformator OCT2 is used to measure electrical equipment electric current, and the secondary outlet of isolating transformer is wound on by optical fiber
On, the secondary outlet of isolating transformer is passed through after the second all-fiber current transformator OCT2, by copper bar or cable through the
After two electromagnetic current transducer CT2, connection system outlet.
The first all-fiber current transformator OCT1 and the second all-fiber current transformator OCT2 pass through optical fiber and two
Secondary protection system is connected, and the first electromagnetic current transducer CT1 and the second electromagnetic current transducer CT2 pass through secondary electricity
Cable is connected with secondary protection system.
Such as Fig. 7, secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop, fourth process
Loop and protection processing unit；
First treatment loop and the 3rd treatment loop are all-fiber current transformator treatment loop, and it includes light letter
Number detector, A/D converter and OCT processing units；
The optical signal detector of first treatment loop and the 3rd treatment loop, which is received, comes from a side unit and secondary
The fiber-optic signal of side unit, and fiber-optic signal is converted into voltage signal, voltage signal is converted to digital letter by A/D converter
Number, data signal is sent to OCT processing units, and OCT processing units do calibration processing to data signal, and according to temperature influence and
Measurement range, it is single that the OCT1 current signals and OCT2 current signals most measured at last is sent to protection processing by communication interface
Member.
The second processing loop and fourth process loop are electromagnetic current transducer treatment loop, electromagnetic type electric current
Transformer treatment loop includes current sensor, A/D converter and CT processing units；
The current sensor in the second processing loop and fourth process loop is received from a side unit and two respectively
The cable signal of secondary side unit, voltage signal is converted to by current sensor, and voltage signal is converted to number by A/D converter
Word signal, data signal is sent to CT processing units, and CT processing units do calibration processing to data signal, most measured at last
CT1 current signals and CT2 current signals are sent to protection processing unit by communication interface；
The protection processing unit receives OCT1 current signals, OCT2 current signals, CT1 current signals and CT2 electric currents letter
Number, carry out differential protection processing.
The transformer is single-phase transformer, three-phase transformer or auto-transformer.
Transformer differential protection method is carried out including following by the photoelectricity CT isolating transformer differential protective systems mixed
Step：
Step 1：Carry out the judgement of differential protection；
If flowing through the first electromagnetic current transducer CT1 and the second electromagnetic current transducer CT2 electric current respectively ICT1
And ICT2, ICT1And ICT2Protection difference Δ Icd2Represent, i.e. Δ Icd2=ICT1-ICT2；
If Δ Icd2＞ Ixz, then show that protection difference is out-of-limit, complete the judgement of differential protection, wherein IxzFor protection difference limit
Value；
Step 2：Carry out the judgement of isolating transformer excitation surge current and the judgement of internal fault；
In transformer during no-load closing, it may appear that excitation surge current, difference current also occurs in transformer both sides, according to above-mentioned
Two kinds of criterions, the differential protection of transformer can also act, therefore excitation surge current of differential protection when needing to escape idle-loaded switching-on.
All-fiber current transformator is identical with the waveform that electromagnetic current transducer is measured during due to power transformer interior fault；Transformation
When excitation surge current occurs for device, the waveform that electromagnetic current transducer is measured can be distorted due to the influence of direct current biasing component,
And the waveform of all-fiber current transformator measurement is relatively accurate, the waveform of two kinds of transformer measurements has certain difference.Therefore can
Excitation surge current is judged with the current differential using two kinds of transformer measurements.
If flowing through the first all-fiber current transformator OCT1 electric currents for IOCT1, IOCT1With ICT1Braking difference Δ Izdc1Table
Show, i.e. Δ Izdc1=IOCT1-ICT1；
If Δ Izdc1＞ Ixz_zd, then show that braking difference is out-of-limit, be determined as that excitation surge current occurs for isolating transformer；Otherwise sentence
It is set to isolating transformer and occurs internal fault, wherein Ixz_zdFor braking difference limit value.
Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention rather than its limitations, institute
The those of ordinary skill in category field with reference to above-described embodiment still can to the present invention embodiment modify or
Equivalent, these any modifications or equivalent without departing from spirit and scope of the invention are applying for this pending hair
Within bright claims.
Claims (3)
1. a kind of isolating transformer differential protecting method of photoelectricity CT mixing, it is characterised in that：It the described method comprises the following steps：
Step 1：Carry out the judgement of differential protection；
If flowing through the first electromagnetic current transducer CT1 and the second electromagnetic current transducer CT2 electric current respectively ICT1With
ICT2, ICT1And ICT2Protection difference Δ Icd2Represent, i.e. Δ Icd2=ICT1-ICT2；
If Δ Icd2＞ Ixz, then show that protection difference is out-of-limit, complete the judgement of differential protection, wherein IxzFor protection difference limit value；
Step 2：Carry out the judgement of isolating transformer excitation surge current and the judgement of internal fault；
If flowing through the first all-fiber current transformator OCT1 electric currents for IOCT1, IOCT1With ICT1Braking difference Δ Izdc1Represent,
That is Δ Izdc1=IOCT1-ICT1；
If Δ Izdc1＞ Ixz_zd, then show that braking difference is out-of-limit, be determined as that excitation surge current occurs for isolating transformer；Otherwise it is determined as
Internal fault, wherein I occur for isolating transformerxz_zdFor braking difference limit value；
Methods described is realized using the photoelectricity CT isolating transformer differential protective systems mixed；
The system goes out including side unit, isolating transformer, secondary side unit, secondary protection system, system inlet wire, a system
Line and breaker；System inlet wire and system outlet are connected to isolating transformer by a side unit and secondary side unit respectively
Primary and secondary side, a side unit and secondary side unit are connected with secondary protection system, and the breaker is located at system
Between inlet wire and a side unit；
Side unit includes the first all-fiber current transformator OCT1 and the first electromagnetic current transducer CT1；It is described
First all-fiber current transformator OCT1 is used to measure electrical equipment electric current, and the primary side inlet wire of isolating transformer is wound on by optical fiber
On, the primary side inlet wire of isolating transformer is passed through after the first all-fiber current transformator OCT1, by copper bar or cable through the
One electromagnetic current transducer CT1, enters back into the primary side of isolating transformer；
The secondary side unit includes the second electromagnetic current transducer CT2；The secondary outlet of the isolating transformer passes through copper
Row or cable pass through the second electromagnetic current transducer CT2, reconnect system outlet；
The first all-fiber current transformator OCT1 is connected by optical fiber with secondary protection system, and the first electromagnetic type electric current is mutual
Sensor CT1 and the second electromagnetic current transducer CT2 are connected by secondary cable with secondary protection system.
2. the isolating transformer differential protecting method of photoelectricity CT mixing according to claim 1, it is characterised in that：Described two
Secondary protection system includes the first treatment loop, second processing loop, the 3rd treatment loop and protection processing unit；
First treatment loop be all-fiber current transformator treatment loop, it include optical signal detector, A/D converter and
OCT processing units；
The optical signal detector of first treatment loop receives the fiber-optic signal from a side unit, and fiber-optic signal is turned
Voltage signal is changed to, voltage signal is converted to data signal by A/D converter, and data signal is sent to OCT processing units,
OCT processing units do calibration processing to data signal, and according to temperature influence and measurement range, the OCT1 electric currents most measured at last
Signal is sent to protection processing unit by communication interface；
The second processing loop and the 3rd treatment loop are electromagnetic current transducer treatment loop, electromagnetic type Current Mutual Inductance
Device treatment loop includes current sensor, A/D converter and CT processing units；
The current sensor of the second processing loop and the 3rd treatment loop is received from a side unit and secondary side respectively
The cable signal of unit, voltage signal is converted to by current sensor, and voltage signal is converted to digital letter by A/D converter
Number, data signal is sent to CT processing units, and CT processing units do calibration processing to data signal, the CT1 electricity most measured at last
Stream signal and CT2 current signals are sent to protection processing unit by communication interface；
The protection processing unit receives OCT1 current signals, CT1 current signals and CT2 current signals, carries out at differential protection
Reason.
3. the isolating transformer differential protecting method of photoelectricity CT mixing according to claim 1, it is characterised in that：It is described every
It is single-phase transformer, three-phase transformer or auto-transformer from transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410741298.1A CN104410045B (en) | 2014-12-05 | 2014-12-05 | The isolating transformer differential protective system and method for a kind of photoelectricity CT mixing |
Applications Claiming Priority (1)
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0833193A (en) * | 1994-07-19 | 1996-02-02 | Hitachi Ltd | Protective relay system for transformer of reception and transformation facility and transformer protection method reception and transformation facility |
| JPH09172729A (en) * | 1995-12-19 | 1997-06-30 | Toshiba Corp | Current differential protective relay device |
| JPH10341527A (en) * | 1997-06-09 | 1998-12-22 | Mitsubishi Electric Corp | Transformer protective relay device |
| CN1682419A (en) * | 2002-07-12 | 2005-10-12 | 麦克劳-爱迪生公司 | Electrical network protection system |
| CN102279300A (en) * | 2011-05-06 | 2011-12-14 | 北京航空航天大学 | All-fiber current transformer open loop signal detection method and apparatus thereof |
| CN103730879A (en) * | 2013-11-22 | 2014-04-16 | 国家电网公司 | Protection device for power utilization system of transformer substation |
-
2014
- 2014-12-05 CN CN201410741298.1A patent/CN104410045B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0833193A (en) * | 1994-07-19 | 1996-02-02 | Hitachi Ltd | Protective relay system for transformer of reception and transformation facility and transformer protection method reception and transformation facility |
| JPH09172729A (en) * | 1995-12-19 | 1997-06-30 | Toshiba Corp | Current differential protective relay device |
| JPH10341527A (en) * | 1997-06-09 | 1998-12-22 | Mitsubishi Electric Corp | Transformer protective relay device |
| CN1682419A (en) * | 2002-07-12 | 2005-10-12 | 麦克劳-爱迪生公司 | Electrical network protection system |
| CN102279300A (en) * | 2011-05-06 | 2011-12-14 | 北京航空航天大学 | All-fiber current transformer open loop signal detection method and apparatus thereof |
| CN103730879A (en) * | 2013-11-22 | 2014-04-16 | 国家电网公司 | Protection device for power utilization system of transformer substation |
Non-Patent Citations (1)
| Title |
|---|
| 光纤电流互感器对变压器差动保护影响的探讨;顾力;《供用电》;20111231;第28卷(第6期);第59-60页 * |
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