CN108931702A - A kind of excitation system low current test abnormality method of discrimination - Google Patents
A kind of excitation system low current test abnormality method of discrimination Download PDFInfo
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- CN108931702A CN108931702A CN201810568383.0A CN201810568383A CN108931702A CN 108931702 A CN108931702 A CN 108931702A CN 201810568383 A CN201810568383 A CN 201810568383A CN 108931702 A CN108931702 A CN 108931702A
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- excitation system
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- low current
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- temperature
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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
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
Abstract
The present invention relates to a kind of excitation system low current test abnormality method of discrimination, technical solution is that A, acquisition rectifier exchange side three-phase input current IA、IB`、ICWith rectifier DC lateral load electric current IR；B, exchange average current I is calculatedAV, difference current ID, direct current average current IF；C, as | IF‑IR|>0.6IRWhen, judge excitation system low current test abnormality；When | IF‑1.2IAV|>0.6IR, when, judge excitation system low current test abnormality；Work as ID>0.6IR, when, judge excitation system low current test abnormality；The present invention passes through on-line monitoring excitation system rectifier current signal, calculate difference current and average current size, the technology status and deterioration rule of equipment can be grasped at any time, with instantaneity, each bridge arm temperature is monitored simultaneously, calculate six bridge arm mean temperatures and is compared with maximum temperature in bridge arm and minimum temperature, as assistant criteria, it avoids sudden accident and control from gradually sending out failure, improves the reliability of system.
Description
Technical field
The present invention relates to a kind of excitation system low current test abnormality method of discrimination, for the different of quick diagnosis excitation system
Normal failure prevents the expansion of accident, belongs to field of measuring technique.
Background technique
Excitation system is generator excited system one of the ost important components, reliability of operation be related to excitation system with
And the stable operation of power grid.When controllable silicon rectifying bridge breaks down, the decline of excitation voltage is not only resulted in, makes excitation transformation
Device is in asymmetric or open-phase running status, it is also possible to which generating dc magnetization phenomenon leads to other mutually silicon-controlled overloads, influences to send out
Motor excitation system is safely and reliably run；Losing its output voltage when power cabinet fuse failure or trigger pulse all will be different
The decline of degree, but since the autoregulation of field regulator, silicon-controlled pilot angle will become smaller, output voltage may be still
The value before failure can be so returned to, but the excitation forcing ratio of excitation system will decline at this time, will affect the safe and stable operation of power grid.
Currently, judge the main rectifier bridge overtemperature of the method for excitation system low current test abnormality and rectifier bridge blower stop transport into
Row judgement.Criterion based on the judgment method is all to measure indirectly, cannot directly reflect the current anomaly sheet of actual moving process
Matter.This includes that temperature signal measurement is easy to produce error, criterion inaccuracy, and temperature change is the process of a gradual change, with electricity
The temporal properties of stream signal are compared, and measurement period is too long, can be used as auxiliary judgment foundation, but the shadow significantly if as main criterion
Ring the timeliness of low current test abnormality judgement；In addition to this, blower travel switch is easy bite, is interfered by own physical characteristic
It is larger, lead to the erroneous judgement of failure.Therefore, it is imperative to improve and innovate.
Summary of the invention
For above situation, for the deficiency for overcoming the prior art, the purpose of the present invention is just to provide a kind of poor with rectifier bridge
Stream is main criterion, using temperature jump as the excitation system low current test abnormality method of discrimination of assistant criteria.
The technical solution that the present invention solves is：
A kind of excitation system low current test abnormality method of discrimination, includes the following steps：
A, acquisition rectifier exchanges side three-phase input current IA、IB`、ICWith rectifier DC lateral load electric current IR；
B, pass through formula：IAV=(IA+IB+ICExchange average current I is calculated in)/3AV；
Pass through formula：
Difference current I is calculatedD；
Pass through formula：
Direct current average current I is calculatedF；
C, as | IF-IR|>0.6IRWhen, judge excitation system low current test abnormality；
When | IF-1.2IAV|>0.6IRWhen, judge excitation system low current test abnormality；
Work as ID>0.6IRWhen, judge excitation system low current test abnormality；
D, when step C judge excitation system low current test it is no abnormal when, using each bridge arm temperature of rectifier as
The assistant criteria of excitation low current test, further determines excitation system low current test abnormality situation；
Specific method is：The temperature T of six transistors in rectifier is acquired by the temperature control measuring point on rectifier first1、
T2、T3、T4、T5、T6；Pass through formula T againAV=(T1+T2+T3+T4+T5+T6The mean temperature of six transistors is calculated in)/6
TAV；Monitoring filters out the temperature maximum T in six temperature of transistor simultaneouslyMAXWith temperature minimum TMIN；
Work as TMIN≥0.8TAVAnd TMAX≤1.2TAVWhen, judge that the test of excitation system low current is normal；
Work as TMIN< 0.8TAVOr TMAX>1.2TAVWhen, judge excitation system low current test abnormality.
The rectifier includes transistor V1、V2、V3、V4、V5、V6, capacitor C and resistance R, transistor V1Emitter connect
Transistor V2Collector, transistor V1Collector distinguish one end of connecting resistance R, one end of capacitor C, transistor V3Current collection
Pole and transistor V5Collector, transistor V2Emitter distinguish the other end of connecting resistance R, the other end of capacitor C, transistor
V4Emitter and transistor V6Emitter, transistor V3Emitter meet transistor V4Collector, transistor V5Transmitting
Pole meets transistor V6Collector, constitute rectifier bridge.
A kind of detection device differentiated for excitation system low current test abnormality, the detection device include controller, the
One AD converter, the second AD converter, Hall sensor, temperature sensor, power supply and alarm, controller respectively with the first AD
Converter, the second AD converter, power supply are connected with alarm, and the first AD converter is connected with Hall sensor, the second AD conversion
Device is connected with temperature sensor, and Hall sensor is for measuring rectifier exchange side three-phase input current IA、IB`、ICWith rectifier
DC side load current IR, and collected current signal is transferred to the first AD converter, it is transferred to after being converted by signal
Controller, temperature signal temperature sensor are used to measure the temperature T of six transistors in rectifier1、T2、T3、T4、T5、T6, and will
Collected temperature signal is transferred to the second AD converter, and controller is transferred to after converting by signal, and controller carries out data
(formula and judgment criteria in such as aforementioned excitation system low current test abnormality method of discrimination in step B-D are handled for processing
Export result), when disconnected excitation system low current test abnormality, alarm equipment alarm.
The invention has the advantages that by on-line monitoring excitation system rectifier current signal, calculate difference current with
Average current size can grasp the technology status and deterioration rule of equipment at any time, have instantaneity, while monitoring each bridge arm temperature
Degree calculates six bridge arm mean temperatures and compares with maximum temperature in bridge arm and minimum temperature, as assistant criteria, avoids happening suddenly
Failure is gradually sent out in sexual behavior event and control, improves the reliability of system, is reduced the unnecessary of equipment and is stopped labour, reduces maintenance cost, increase
Equipment can utilize the time, to improve equipment operating maintenance benefit；Reduce the failure rate of excitation system power unit, Ji Kewei
The strong of excitation system encourages ability when holding electric network fault, and then guarantees the safe and stable operation of power grid, and easy to use, effect is good, has
Good social and economic benefit.
Detailed description of the invention
Fig. 1 is the frame figure of detection device of the present invention.
Fig. 2 is the circuit diagram of electric current of the present invention and temperature acquisition.
Specific embodiment
Below in conjunction with attached drawing, specific embodiments of the present invention will be described in further detail.
As shown in Figs. 1-2, the present invention relates to a kind of excitation system low current test abnormality method of discrimination, including following step
Suddenly：
A, acquisition rectifier exchanges side three-phase input current IA、IB`、ICWith rectifier DC lateral load electric current IR；
B, pass through formula：IAV=(IA+IB+ICExchange average current I is calculated in)/3AV；
Pass through formula：
Difference current I is calculatedD；
Pass through formula：
Direct current average current I is calculatedF；
C, as | IF-IR|>0.6IRWhen, judge excitation system low current test abnormality, when low current test is normal, direct current is flat
Equal electric current is approximately equal with DC side load current；
When | IF-1.2IAV|>0.6IRWhen, judge excitation system low current test abnormality, when low current test is normal, direct current
Average current IFWith exchange average current reduction value 1.2IAVValue it is approximately equal；
Work as ID>0.6IRWhen, judge excitation system low current test abnormality, when low current test is normal, which is answered
It is approximately equal to zero；
D, when step C judge excitation system low current test it is no abnormal when, using each bridge arm temperature of rectifier as
The assistant criteria of excitation low current test, further determines excitation system low current test abnormality situation；
Specific method is：The temperature T of six transistors in rectifier is acquired by the temperature control measuring point on rectifier first1、
T2、T3、T4、T5、T6；Pass through formula T againAV=(T1+T2+T3+T4+T5+T6The mean temperature of six transistors is calculated in)/6
TAV；Monitoring filters out the temperature maximum T in six temperature of transistor simultaneouslyMAXWith temperature minimum TMIN；
Work as TMIN≥0.8TAVAnd TMAX≤1.2TAVWhen, judge that the test of excitation system low current is normal；
Work as TMIN< 0.8TAVOr TMAX>1.2TAVWhen, judge excitation system low current test abnormality.
To guarantee using effect, the rectifier includes transistor V1、V2、V3、V4、V5、V6, capacitor C and resistance R are brilliant
Body pipe V1Emitter meet transistor V2Collector, transistor V1Collector difference one end of connecting resistance R, capacitor C one
End, transistor V3Collector and transistor V5Collector, transistor V2Emitter difference connecting resistance R the other end, capacitor
The other end, the transistor V of C4Emitter and transistor V6Emitter, transistor V3Emitter meet transistor V4Current collection
Pole, transistor V5Emitter meet transistor V6Collector, constitute rectifier bridge；
The transistor is insulated gate bipolar transistor (IGBT).
A kind of detection device differentiated for excitation system low current test abnormality, the detection device include controller, the
One AD converter, the second AD converter, Hall sensor, temperature sensor, power supply and alarm, controller respectively with the first AD
Converter, the second AD converter, power supply are connected with alarm, and the first AD converter is connected with Hall sensor, the second AD conversion
Device is connected with temperature sensor, and Hall sensor is for measuring rectifier exchange side three-phase input current IA、IB`、ICWith rectifier
DC side load current IR, and collected current signal is transferred to the first AD converter, it is transferred to after being converted by signal
Controller, temperature signal temperature sensor are used to measure the temperature T of six transistors in rectifier1、T2、T3、T4、T5、T6, and will
Collected temperature signal is transferred to the second AD converter, and controller is transferred to after converting by signal, and controller carries out data
(formula and judgment criteria in such as aforementioned excitation system low current test abnormality method of discrimination in step B-D are handled for processing
Export result), when disconnected excitation system low current test abnormality, alarm equipment alarm；The alarm is warning lamp or buzzing
The combination of device or both.
Transistor V1Emitter and transistor V2The total end of collector is as exchange side three-phase input current IAMeasuring point；
Transistor V3Emitter and transistor V4The total end of collector is as exchange side three-phase input current IB`Measuring point；
Transistor V5Emitter and transistor V6The total end of collector is as exchange side three-phase input current ICMeasuring point；
The total end of resistance R and capacitor C is as DC side load current IRMeasuring point；
Transistor V1Collector as temperature T1Measuring point；Transistor V2Emitter as temperature T2Measuring point；
Transistor V3Collector as temperature T3Measuring point；Transistor V4Emitter as temperature T4Measuring point；
Transistor V5Collector as temperature T5Measuring point；Transistor V6Emitter as temperature T6Measuring point.
The controller is the prior art (commercial product), can receive electric current and temperature letter that AD converter conversion comes
Number, and formula in aforementioned excitation system low current test abnormality method of discrimination in step B-D and judgment criteria are handled simultaneously
Output is as a result, such as can be used 32 fixed-point dsps of TMS320F2812 of TI company production；
The Hall sensor is the prior art (commercial product), can measure rectifier exchange side three-phase input current
With rectifier DC lateral load electric current, and by current signal be transferred to the first AD converter carry out data conversion, LEM such as can be used
The Hall sensor of the model LA55-P/SP50 of company's production；
The temperature sensor is the prior art (commercial product), can measure the temperature of six transistors in rectifier
Degree, and temperature signal is transferred to the second AD converter and carries out data conversion, the model of JUMO company production such as can be used
The temperature sensor of PT100；
First AD converter, the second AD converter prior art (commercial product) are used for data conversion, can such as adopt
With the A/D conversion module etc. of model AD606；
The present invention judges that the main criterion of excitation system low current test abnormality is rectifier bridge difference stream, when the function of excitation system
When rate bridge module operates normally, is removed outside the loss of rectifier bridge own power according to the power at its rectifier bridge both ends, exchange side function
Rate is approximately equal to its DC side power, i.e. Pac=Pdc+P0Wherein PdcIndicate rectification bridge DC side power, PacIndicate that rectifier bridge is handed over
Flow side power, P0Indicate the loss of rectifier own power, exchange side power is approximately equal to DC side when rectifier bridge operates normally
Power, when rectifier operates normally, the power module conducting shutdown of each bridge arm is often almost the same, therefore six power module hairs
Hot degree also answer it is approximately equal, if wherein there is some power module to cut-off exception, such as module itself aging, then should have at this compared with
For apparent temperature rise.That is, the present invention by on-line monitoring excitation system rectifier current signal, calculate difference current with
Stalling current size can grasp the technology status and deterioration rule of equipment at any time, have instantaneity, while monitoring each bridge arm temperature
Degree calculates six bridge arm mean temperatures and compares with maximum temperature in bridge arm and minimum temperature, as assistant criteria, avoids happening suddenly
Failure is gradually sent out in sexual behavior event and control, improves the reliability of system, is reduced the unnecessary of equipment and is stopped labour, reduces maintenance cost, increase
Equipment can utilize the time, to improve equipment operating maintenance benefit；Reduce the failure rate of excitation system power unit, Ji Kewei
The strong of excitation system encourages ability when holding electric network fault, through practical application, achieves identical or similar testing result, accurately
Rate has nearly reached 100%, and the safe and stable operation of power grid is effectively ensured, and has good social and economic benefit.
Claims (5)
1. a kind of excitation system low current test abnormality method of discrimination, which is characterized in that include the following steps：
A, acquisition rectifier exchanges side three-phase input current IA、IB`、ICWith rectifier DC lateral load electric current IR；
B, pass through formula：IAV=(IA+IB+ICExchange average current I is calculated in)/3AV；
Pass through formula：
Difference current I is calculatedD；
Pass through formula：
Direct current average current I is calculatedF；
C, as | IF-IR|>0.6IRWhen, judge excitation system low current test abnormality；
When | IF-1.2IAV|>0.6IRWhen, judge excitation system low current test abnormality；
Work as ID>0.6IRWhen, judge excitation system low current test abnormality；
D, when step C judges that the test of excitation system low current is no abnormal, using each bridge arm temperature of rectifier as excitation
The assistant criteria of low current test, further determines excitation system low current test abnormality situation；
Specific method is：The temperature T of six transistors in rectifier is acquired by the temperature control measuring point on rectifier first1、T2、T3、
T4、T5、T6；Pass through formula T againAV=(T1+T2+T3+T4+T5+T6The mean temperature T of six transistors is calculated in)/6AV；Together
When monitoring filter out temperature maximum T in six temperature of transistorMAXWith temperature minimum TMIN；
Work as TMIN≥0.8TAVAnd TMAX≤1.2TAVWhen, judge that the test of excitation system low current is normal；
Work as TMIN< 0.8TAVOr TMAX>1.2TAVWhen, judge excitation system low current test abnormality.
2. excitation system low current test abnormality method of discrimination according to claim 1, which is characterized in that the rectification
Device includes transistor V1、V2、V3、V4、V5、V6, capacitor C and resistance R, transistor V1Emitter meet transistor V2Collector, it is brilliant
Body pipe V1Collector distinguish one end of connecting resistance R, one end of capacitor C, transistor V3Collector and transistor V5Current collection
Pole, transistor V2Emitter distinguish the other end of connecting resistance R, the other end of capacitor C, transistor V4Emitter and transistor
V6Emitter, transistor V3Emitter meet transistor V4Collector, transistor V5Emitter meet transistor V6Current collection
Pole constitutes rectifier bridge.
3. excitation system low current test abnormality method of discrimination according to claim 1, which is characterized in that the crystal
Pipe is insulated gate bipolar transistor.
4. a kind of detection device differentiated for excitation system low current test abnormality, which is characterized in that the detection device includes
Controller, the first AD converter, the second AD converter, Hall sensor, temperature sensor, power supply and alarm, controller point
It is not connected with the first AD converter, the second AD converter, power supply and alarm, the first AD converter is connected with Hall sensor,
Second AD converter is connected with temperature sensor, and Hall sensor is for measuring rectifier exchange side three-phase input current IA、IB`、
ICWith rectifier DC lateral load electric current IR, and collected current signal is transferred to the first AD converter, it is converted by signal
After be transferred to controller, temperature signal temperature sensor is used to measure the temperature T of six transistors in rectifier1、T2、T3、T4、
T5、T6, and collected temperature signal is transferred to the second AD converter, controller, controller are transferred to after converting by signal
Carry out data processing, when disconnected excitation system low current test abnormality, alarm equipment alarm.
5. the detection device according to claim 4 differentiated for excitation system low current test abnormality, which is characterized in that
The alarm is the combination of warning lamp or buzzer or both.
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| CN201810568383.0A CN108931702B (en) | 2018-06-05 | 2018-06-05 | Method for judging small current test abnormity of excitation system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114113918A (en) * | 2021-12-23 | 2022-03-01 | 国网浙江省电力有限公司经济技术研究院 | Fault detection method and system |
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