CN110380384A - A method of judging that main transformer sky fills excitation surge current and influences direct current transportation - Google Patents
A method of judging that main transformer sky fills excitation surge current and influences direct current transportation Download PDFInfo
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- CN110380384A CN110380384A CN201810328974.0A CN201810328974A CN110380384A CN 110380384 A CN110380384 A CN 110380384A CN 201810328974 A CN201810328974 A CN 201810328974A CN 110380384 A CN110380384 A CN 110380384A
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- main transformer
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- direct current
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- excitation surge
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/50—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to the appearance of abnormal wave forms, e.g. ac in dc installations
- H02H3/52—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to the appearance of abnormal wave forms, e.g. ac in dc installations responsive to the appearance of harmonics
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Protection Of Transformers (AREA)
Abstract
The present invention discloses a kind of method for judging main transformer sky and filling excitation surge current influence direct current transportation, judges whether to meet following 3 conditions, if all meeting, after the t that is delayed, determines that main transformer sky fills excitation surge current and influences direct current transportation, output action signal；3 conditions are respectively: there are main transformer skies to fill switching signal, meets AC network electrical quantity distortion criterion, meets DC transmission system electrical quantity variation criterion.Such method can identify that excitation surge current will lead to direct current transportation exception from source, then take disconnection sky to fill the operation such as transformer, cut off excitation surge current source, guarantee extra-high voltage alternating current-direct current serial-parallel power grid safe and stable operation.
Description
Technical field
Filling excitation surge current the present invention relates to a kind of judgement main transformer sky influences the method for direct current transportation, is suitable for AC and DC transmission
Combined hybrid system and alternating current and direct current control protective unit.
Background technique
It include ac grid system and single or a plurality of DC transmission system in AC and DC transmission combined hybrid system, wherein exchanging
Network system is made of numerous alternating current circuits and numerous substations (or power station, electricity consumption user).AC network presses voltage class
It divides, each voltage class power grid is connected by AC transformer, forms a huge power transmission electric network.
China's extra-high voltage grid builds period at present, and tetanic weak friendship phenomenon is obvious, in AC-DC hybrid power grid, once goes out
Now crossing the hollow excitation surge current for filling AC transformer (containing converter power transformer) generation of AC network causes DC transmission system bipolar
Phenomena such as locking, power return drop and oscillation of power, threatens the safe operation of power grid.It is exemplified below:
Northwest Grid Guan Ting substation in 2011 carries out 750kV main transformer closing operation, and the Qinghai-Tibet between trial run period is straight
100Hz protection act is flowed, direct current is latched.
2014 Nian Xiluo cross the operation of the Niu Congjia DC bipolar 1550MW among double back direct current transportation, and ox stockaded village station is carrying out ox
When from 1 inverter charging of second pole, occurs 50Hz component in Niu Congjia DC current, 50Hz protection issues handover control system and function
Rate returns the request of drop, and Niu Congjia DC bipolar power is reduced to 960MW.
Heihe converter station direct current protecting 50Hz protection act in 2016, direct current locking.Preliminary analysis thinks that Russian side becomes
It is maximum that depressor charging generates a possibility that excitation surge current causes alternating voltage distortion.
The bipolar Ground return total pressure operation of 2016 Nian Tianzhong extra-high voltage direct-currents, the port owned by the government Central China Power Grid 500kV station #1 main transformer fill
Electricity, B phase excitation surge current virtual value reach 1136A, decay to 10% after continuing 15s.Cause in day direct current active power peak valley most
Big difference reaches 700MW.Through analyzing, converter station ac bus voltage contains biggish Zero-pharse harmonic component, which makes
It obtains commutation failure forecast function criterion to meet and act, Trigger Angle reduces 8 degree.
For take place frequently caused due to AC system main transformer charging operations DC transmission system power return drop, locking and
Phenomena such as power disturbance, previous measure concentrate on the selection of direct current protecting algorithm locking criterion, the setting principle of definite value and adjustment,
The feature of the excitation surge current of AC transformer, etc..It identifies that excitation surge current will lead to direct current transportation exception from source, then takes
It disconnects sky and fills the measures such as transformer, cut off excitation surge current source, so that it is guaranteed that the measures such as direct current transportation normal operation, this aspect
Technology there is presently no appearance.
Therefore, it has an immense impact on, mentions to AC-DC hybrid power grid system stabilization for AC system main transformer charging operations
Corresponding countermeasure out will play an important role China's AC-DC hybrid power grid safe and stable operation.
Summary of the invention
The purpose of the present invention, being to provide a kind of judgement main transformer sky and filling excitation surge current influences the method for direct current transportation, can
It identifies that excitation surge current will lead to direct current transportation exception from source, then takes disconnection sky to fill the operation such as transformer, cut off excitation
It shoves source, guarantees extra-high voltage alternating current-direct current serial-parallel power grid safe and stable operation.
In order to achieve the above objectives, solution of the invention is:
A method of judging that main transformer sky fills excitation surge current and influences direct current transportation, judges whether to meet following 3 conditions, if
All meet, then after the t that is delayed, determines that main transformer sky fills excitation surge current and influences direct current transportation, output action signal；3 items
Part is respectively: there are main transformer skies to fill switching signal, meets AC network electrical quantity distortion criterion, it is electrical to meet DC transmission system
Amount variation criterion.
It is main transformer switch closing position signal or main transformer switch combined floodgate command signal that above-mentioned main transformer sky, which fills switching signal,.
The content of above-mentioned AC network electrical quantity distortion criterion is: according to: a1, alternating voltage total harmonic distortion, fundamental wave remove
Outside, b1, alternating current total harmonic distortion, except fundamental wave, c1, alternating voltage secondary harmonic component, d1, alternating current second harmonic
Content, e1, alternating voltage triple-frequency harmonics content, f1, alternating current triple-frequency harmonics content, the friendship added up during g1, a cycle
Galvanic electricity presses the mean square deviation of current value and several Zhou Boqian numerical value, the alternating current current value added up during h1, a cycle
With the mean square deviation of several Zhou Boqian numerical value；Differentiate that calculated value listed by a1 to h1 is greater than respective threshold value, and by respective
Be delayed tx, x is subscript, respectively represents a1, b1, c1, d1, e1, f1, g1, h1；AC network electrical quantity distortion criterion uses a1 extremely
Single differentiation listed by h1, or combined using listed any m differentiation, m=2,3 ..., 7, or sentenced using listed whole
Not.
The electrical quantity that differentiation uses listed by above-mentioned a1 to h1 is the data in the same substation in AC network, or
The data in different substation in AC network.
The content of above-mentioned DC transmission system electrical quantity variation criterion is: according to: alternating current net side in a2, DC converter station
Voltage zero-sequence component, the voltage alpha-beta component of alternating current net side in b2, DC converter station, the fundamental wave content of c2, DC current are d2, straight
The secondary harmonic component of galvanic electricity stream, the triple-frequency harmonics content of e2, DC current, commutation failure is detected in f2, DC converter station
To signal；Differentiate that calculated value listed by a2 to e2 is greater than respective threshold value, and passes through respective delay ty, y is subscript, respectively
Represent a2, b2, c2, d2, e2；DC transmission system electrical quantity changes criterion using single differentiation listed by a2 to f2, or uses
Listed any n differentiation combination, n=2,3,4, or using listed whole differentiations.
The action signal of above-mentioned output includes: a3, alarm, and b3, disjunction main transformer threephase switch, c3, disjunction main transformer excitation are gushed
The big single-phase switch of fluxion value, d3, DC power transmission control system adjustment blow-out angle amplitude of variation and speed, e3, adjustment direct current change
The threshold value of the voltage zero-sequence component of alternating current net side in stream station, f3, the voltage alpha-beta component for adjusting alternating current net side in DC converter station
Threshold value；Output action signal is individual part signal listed by a3 to f3 or listed any p action signal group
It closes, p=2,3,4,5 or listed whole action signals.
The value range of above-mentioned delay t is 5ms to 800ms.
After adopting the above scheme, the present invention judges item when meeting by judging AC system main transformer charging operations
When part, the operation such as transformer is filled using sky is disconnected, excitation surge current source is cut off or reduces influence amplitude, can guarantee that extra-high voltage is handed over
Direct current serial-parallel power grid safe and stable operation.
Detailed description of the invention
Fig. 1 is general flow chart of the invention.
Specific embodiment
As shown in Figure 1, the present invention provides a kind of method for judging main transformer sky and filling excitation surge current influence direct current transportation, specifically
According to: (1) main transformer sky fill switching signal, (2) AC network electrical quantity distortion criterion, the variation of (3) DC transmission system electrical quantity
Criterion, if these three conditions all meet, then being judged as that main transformer sky fills excitation surge current and influences after certain delay t
Direct current transportation, output action signal.
Wherein, the main transformer sky, which fills switching signal, can be main transformer switch closing position signal, is also possible to main transformer and opens
Close lock command signal.
The content of AC network electrical quantity distortion criterion is: a1, alternating voltage total harmonic distortion (except fundamental wave), b1, friendship
Galvanic electricity stream total harmonic distortion (except fundamental wave), c1, alternating voltage secondary harmonic component, d1, alternating current secondary harmonic component,
E1, alternating voltage triple-frequency harmonics content, f1, alternating current triple-frequency harmonics content, the alternating voltage added up during g1, a cycle
The mean square deviation of current value and several Zhou Boqian numerical value, the alternating current current value added up during h1, a cycle with it is several
The mean square deviation of Zhou Boqian numerical value；Differentiate that calculated value listed by a1 to h1 is greater than respective threshold value, and passes through respective delay tx
(x is subscript, respectively a1, b1, c1, d1, e1, f1, g1, h1)；AC network electrical quantity distortion criterion is listed by a1 to h1
It is single to differentiate listed several differentiations combination or listed whole differentiations；Differentiation listed by a1 to h1 uses
Electrical quantity can be the data in the same substation in AC network, be also possible in the different substation in AC network
Data.
The content of DC transmission system electrical quantity variation criterion is: the voltage zero sequence of alternating current net side in a2, DC converter station
Component, the voltage alpha-beta component of alternating current net side in b2, DC converter station, the fundamental wave content of c2, DC current, d2, DC current
Secondary harmonic component, the triple-frequency harmonics content of e2, DC current, commutation failure is detected signal in f2, DC converter station；Sentence
Calculated value listed by other a2 to e2 is greater than respective threshold value, and passes through respective delay ty(y is subscript, respectively a2, b2,
C2, d2, e2)；DC transmission system electrical quantity variation criterion is single differentiation listed by a2 to f2 or listed several sentences
It does not combine or listed whole differentiates.
Wherein, the action signal of output includes: a3, alarm, and b3, disjunction main transformer threephase switch, c3, disjunction main transformer excitation are gushed
The big single-phase switch of fluxion value, d3, DC power transmission control system adjustment blow-out angle amplitude of variation and speed, e3, adjustment direct current change
The threshold value of the voltage zero-sequence component of alternating current net side in stream station, f3, the voltage alpha-beta component for adjusting alternating current net side in DC converter station
Threshold value；Output action signal is that individual part signal listed by a3 to f3 or listed several action signals combine,
Either listed whole action signals.
The value range of delay t is 5ms to 800ms.
Technical solution of the present invention will be further described by specific embodiment below.
Embodiment 1: assuming that in an AC-DC hybrid power grid system, including substation A, substation B, direct current transportation are changed
Stream station C and other numerous substations；These substations and converter station are connected by transmission line of alternation current.Wherein, power transformation
The A that stands includes main transformer D and other main transformers and numerous alternating current circuits, and main transformer D does not access power grid；Substation B has an AC line
Road E and other alternating current circuits and numerous main transformers.The positive rated power operation of direct-current transmission converter station C.
Substation A operations staff is connected to dispatching of power netwoks department main transformer D and puts into operation instruction.According to the method for the present invention: reading
Main transformer D closing position signal H1；The second harmonic component for calculating substation A main transformer D primary side alternating voltage, with threshold value S1 ratio
Compared be delayed tc1, obtains signal H2；The third-harmonic component for calculating the alternating current circuit substation B E alternating current, with threshold value S2 ratio
Compared be delayed tf1, obtains signal H3；The second harmonic component for calculating direct-current transmission converter station C DC current, with threshold value S3 ratio
Compared be delayed td2, obtains signal H4；Signal H1, H2, H3, H4 are carried out and logical operation, is delayed t (taking 20ms), output action letter
Number: disjunction substation A main transformer D threephase switch.
Embodiment 2: assuming that in an AC-DC hybrid power grid system, including substation A, substation B, direct current transportation are changed
Stream station C and other numerous substations；These substations and converter station are connected by transmission line of alternation current.Wherein, substation
A includes main transformer D and other main transformers and numerous alternating current circuits, and main transformer D does not access power grid；Substation B has an alternating current circuit
E and other alternating current circuits and numerous main transformers.The positive rated power operation of direct-current transmission converter station C.
Substation A operations staff is connected to dispatching of power netwoks department main transformer D and puts into operation instruction.According to the method for the present invention: reading
Main transformer D closing position signal H1；The second harmonic component for calculating substation A main transformer D primary side alternating voltage, with threshold value S1 ratio
Compared be delayed tc1, obtains signal H2；The third-harmonic component for calculating substation A main transformer D pair side alternating current, with threshold value S2 ratio
Compared be delayed tf1, obtains signal H3；Calculate the alternating voltage current value added up during mono- cycle of substation B alternating current circuit E
With the mean square deviation of several Zhou Boqian numerical value, compared with threshold value S3, be delayed tg1, obtains signal H4；Read direct-current transmission converter station
Commutation failure is detected signal H5 in C；Signal H1, H2, H3, H4, H5 are carried out and logical operation, is delayed t (taking 30ms), output
Action signal: disjunction substation A main transformer D threephase switch, and increase the blow-out angle of direct-current transmission converter station C.
The above examples only illustrate the technical idea of the present invention, and this does not limit the scope of protection of the present invention, all
According to the technical idea provided by the invention, any changes made on the basis of the technical scheme each falls within the scope of the present invention
Within.
Claims (7)
1. a kind of judgement main transformer sky, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that: judge whether to meet following 3
A condition after the t that is delayed, determines that main transformer sky fills excitation surge current and influences direct current transportation, output action letter if all meeting
Number；3 conditions are respectively: there are main transformer skies to fill switching signal, meets AC network electrical quantity distortion criterion, meets direct current transportation
System electrical amount changes criterion.
2. a kind of judgement main transformer sky as described in claim 1, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
It is main transformer switch closing position signal or main transformer switch combined floodgate command signal that the main transformer sky, which fills switching signal,.
3. a kind of judgement main transformer sky as described in claim 1, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
The content of AC network electrical quantity distortion criterion is: according to a1, alternating voltage total harmonic distortion, except fundamental wave, and b1, friendship
Galvanic electricity stream total harmonic distortion, except fundamental wave, c1, alternating voltage secondary harmonic component, d1, alternating current secondary harmonic component, e1,
Alternating voltage triple-frequency harmonics content, f1, alternating current triple-frequency harmonics content, the alternating voltage added up during g1, a cycle are worked as
The mean square deviation of preceding numerical value and several Zhou Boqian numerical value, the alternating current current value added up during h1, a cycle and several weeks
The mean square deviation of wavefront numerical value；Differentiate that calculated value listed by a1 to h1 is greater than respective threshold value, and passes through respective delay tx, x
For subscript, a1, b1, c1, d1, e1, f1, g1, h1 are respectively represented；AC network electrical quantity distorts criterion using listed by a1 to h1
Single differentiation, or combined using listed any m differentiation, m=2,3 ..., 7, or using listed whole differentiations.
4. a kind of judgement main transformer sky as claimed in claim 3, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
The electrical quantity that differentiation uses listed by the a1 to h1 is data or AC network in the same substation in AC network
In different substation in data.
5. a kind of judgement main transformer sky as described in claim 1, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
The content of the DC transmission system electrical quantity variation criterion is: according to: the voltage zero sequence of alternating current net side in a2, DC converter station
Component, the voltage alpha-beta component of alternating current net side in b2, DC converter station, the fundamental wave content of c2, DC current, d2, DC current
Secondary harmonic component, the triple-frequency harmonics content of e2, DC current, commutation failure is detected signal in f2, DC converter station；Sentence
Calculated value listed by other a2 to e2 is greater than respective threshold value, and passes through respective delay ty, y is subscript, a2 is respectively represented,
B2, c2, d2, e2；DC transmission system electrical quantity changes criterion using single differentiation listed by a2 to f2, or is appointed using listed
N differentiation combination of meaning, n=2,3,4, or using listed whole differentiations.
6. a kind of judgement main transformer sky as described in claim 1, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
The action signal of the output includes: a3, alarm, and b3, disjunction main transformer threephase switch, c3, disjunction main transformer excitation surge current numerical value are big
Single-phase switch, d3, DC power transmission control system adjustment blow-out angle amplitude of variation and speed are handed in e3, adjustment DC converter station
The threshold value of the voltage zero-sequence component of drift net side, f3, the threshold for adjusting the voltage alpha-beta component of alternating current net side in DC converter station
Value；Output action signal is individual part signal listed by a3 to f3 or listed any p action signal combination, p=
2,3,4,5 or listed whole action signals.
7. a kind of judgement main transformer sky as described in claim 1, which fills excitation surge current, influences the method for direct current transportation, it is characterised in that:
The value range of the delay t is 5ms to 800ms.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810328974.0A CN110380384B (en) | 2018-04-13 | 2018-04-13 | Method for judging influence of main variable-air charging excitation inrush current on direct-current transmission |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810328974.0A CN110380384B (en) | 2018-04-13 | 2018-04-13 | Method for judging influence of main variable-air charging excitation inrush current on direct-current transmission |
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| CN110380384A true CN110380384A (en) | 2019-10-25 |
| CN110380384B CN110380384B (en) | 2021-07-27 |
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| CN201810328974.0A Active CN110380384B (en) | 2018-04-13 | 2018-04-13 | Method for judging influence of main variable-air charging excitation inrush current on direct-current transmission |
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| WO1994018748A1 (en) * | 1993-02-12 | 1994-08-18 | Valor Electronics, Inc. | Control circuit for a switching dc-dc power converter including a controlled magnetic core flux resetting technique for output regulation |
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| CN103296673A (en) * | 2013-05-09 | 2013-09-11 | 国家电网公司 | Debugging method for +/- 800 kV ultra-high voltage direct-current transmission project system |
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