CN110323773A - A kind of commutation failure prediction technique and system considering multifactor impact - Google Patents
A kind of commutation failure prediction technique and system considering multifactor impact Download PDFInfo
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- CN110323773A CN110323773A CN201910595078.5A CN201910595078A CN110323773A CN 110323773 A CN110323773 A CN 110323773A CN 201910595078 A CN201910595078 A CN 201910595078A CN 110323773 A CN110323773 A CN 110323773A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
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Abstract
The invention discloses a kind of commutation failure prediction techniques and system for considering multifactor impact, comprising: calculates the value of each impact factor；Commutation failure value-at-risk is calculated according to the value of each impact factor and the commutation failure influence degree of the impact factor；The commutation failure value-at-risk is compared with preset commutation failure risk criterion, to predict whether converter station has occurred commutation failure.The commutation failure prediction technique of consideration multifactor impact of the invention considers a variety of impact factors for leading to commutation failure, commutation failure risk criterion is determined, and commutation failure has occurred right and is predicted for the commutation failure value-at-risk and commutation failure risk criterion that determine according to these factors；It according to the transient characterisitics at the phase angle of converter station ac-side current when commutation failure can identify whether that commutation failure has occurred well；Meanwhile the accuracy and efficiency of prediction and identification are improved using method of the invention.
Description
Technical field
The present invention relates to technical field of relay protection, and more particularly, to a kind of commutation for considering multifactor impact
Failure prediction method and system.
Background technique
The converter station of high voltage direct current transmission project carries the function of mutually converting alternating current and direct current.Converter station is again
It is divided into rectification side and inverter side, when inverter side converter valve is by extraneous or internal interference, the converter valve that should be turned off is still
Do not restore to bear forward voltage again when blocking ability, is connected and switches again so as to cause the valve that should be turned off
Phase.The still normal commutation of the valve of another pole at this time forms bypass with the valve for switching phase and causes valve dc-side short-circuit, this phenomenon is referred to as
For commutation failure.After commutation failure occurs for direct current system, fluctuation by a relatively large margin occurs for the power that direct current can be made to send out.By
It is the intrinsic element characteristic due to the thyristor in DC converter valve in commutation failure and causes, single commutation failure can not
It avoids, identifies and inhibited if cannot timely be detected to it, will lead to the multiple commutation failure of direct current system generation and cause
Direct current locking, or cause multiple-circuit line and commutation failure occurs simultaneously, the security and stability of direct current receiving end AC system is caused
Serious impact.
The detection method in engineering for commutation failure is broadly divided into two kinds at present, actual measurement type and forecasting type.Actual measurement type is logical
It crosses and calculates at the time of each valve electric current is zero and the time interval of difference at the time of commutation voltage zero passage, be converted to angle to obtain
Blow-out angle, and be compared with limit blow-out angle to determine whether commutation failure occurs, such as Tianguang HVDC system.Forecasting type is
By extract AC fault occur after negative sequence component or comparison DC current and valve current maxima difference to determine whether
DC Line Fault occurs to judge commutation failure, but there are still identification dead zones, such as control system trigger pulse to lose, is humorous
Wave action etc. may make it generate erroneous judgement, and Consideration is insufficient.And utilize commutation voltage, the single factors such as DC current
The method for judging commutation failure, it is quasi- under the complex working condition in face of multi-infeed HVDC access and large-scale distributed power grid
True property can be declined.
Therefore, it is necessary to a kind of methods predicted commutation failure for considering multifactor impact.
Summary of the invention
The present invention proposes a kind of commutation failure prediction technique and system for considering multifactor impact, how to solve to the change of current
It stands and whether the problem of commutation failure is predicted occurs.
To solve the above-mentioned problems, according to an aspect of the invention, there is provided a kind of commutation for considering multifactor impact
Failure prediction method, which comprises
Calculate the value of each impact factor；Wherein, the impact factor includes: the commutation voltage factor, harmonic factor, direct current
At least two in current factor, valve current factor and the trigger pulse factor；
Commutation failure risk is calculated according to the value of each impact factor and the commutation failure influence degree of the impact factor
Value；
The commutation failure value-at-risk is compared with preset commutation failure risk criterion, whether to send out converter station
Commutation failure has been given birth to be predicted.
Preferably, wherein the value for calculating each impact factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1It opens
Begin to calculate, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve
When the absolute value of electric current is less than preset valve electric current threshold value；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome from 0
Pmin, maintain to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is big
In preset valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electricity
When flowing threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy
PminBecome Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor harmonic factor
Value；V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Electric current；PIvFor the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
Preferably, wherein it is described according to the value of each impact factor and the commutation failure influence degree meter of the impact factor
Calculate commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th
The value of a impact factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
Preferably, wherein determining the commutation failure influence degree of each impact factor using such as under type:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor preset i-th of impact factor
Commutation failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th
The value of a impact factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor preset i-th of impact factor
Value maximum value.
Preferably, wherein the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation does not occur for prediction result instruction converter station
Failure；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and it is fixed to be less than preset outlet
Value, then commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result indicates converter station meeting
Commutation failure occurs.
Preferably, wherein the method also includes:
When commutation failure may occur for prediction result instruction converter station, the electric current phase of the converter station exchange side of acquisition is calculated
The integrated value of the absolute value of the derivative of parallactic angle, and when the integrated value is less than 0, determine that commutation failure has occurred for converter station.
According to another aspect of the present invention, a kind of commutation failure forecasting system for considering multifactor impact, institute are provided
The system of stating includes:
The value computing unit of impact factor, for calculating the value of each impact factor；Wherein, the impact factor includes:
At least two in the commutation voltage factor, harmonic factor, the DC current factor, valve current factor and the trigger pulse factor；
Commutation failure value-at-risk computing unit, for being lost according to the value of each impact factor and the commutation of the impact factor
It loses influence degree and calculates commutation failure value-at-risk；
Commutation failure predicting unit, for carrying out the commutation failure value-at-risk and preset commutation failure risk criterion
Compare, to predict whether converter station has occurred commutation failure.
Preferably, wherein the value computing unit of the impact factor, calculates the value of each impact factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1It opens
Begin to calculate, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve
When the absolute value of electric current is less than preset valve electric current threshold value；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome from 0
Pmin, maintain to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is big
In preset valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electricity
When flowing threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy
PminBecome Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor harmonic factor
Value；V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Electric current；PIvFor the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
Preferably, wherein the commutation failure value-at-risk computing unit, according to the value of each impact factor and the influence
The commutation failure influence degree of the factor calculates commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th
The value of a impact factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
Preferably, wherein determining the commutation failure influence degree of each impact factor using such as under type:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor preset i-th of impact factor
Commutation failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th
The value of a impact factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor preset i-th of impact factor
Value maximum value.
Preferably, wherein the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation does not occur for prediction result instruction converter station
Failure；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and it is fixed to be less than preset outlet
Value, then commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result indicates converter station meeting
Commutation failure occurs.
Preferably, wherein the system also includes:
Commutation failure recognition unit, for calculating acquisition when commutation failure may occur for prediction result instruction converter station
Converter station exchange side current phase angle derivative absolute value integrated value, and when the integrated value is less than 0, determination is changed
Commutation failure has occurred for stream station.
The present invention provides a kind of commutation failure prediction techniques and system for considering multifactor impact, comprising: calculates each
The value of impact factor；Commutation failure is calculated according to the value of each impact factor and the commutation failure influence degree of the impact factor
Value-at-risk；The commutation failure value-at-risk is compared with preset commutation failure risk criterion, whether to send out converter station
Commutation failure has been given birth to be predicted.The present invention considers a variety of impact factors for leading to commutation failure, it is determined that commutation failure wind
Dangerous criterion, and commutation failure has occurred in the commutation failure value-at-risk and commutation failure risk criterion that are determined according to these factors right
It is predicted；Can be identified well according to the transient characterisitics at the phase angle of converter station ac-side current when commutation failure is
It is no that commutation failure has occurred；Meanwhile the accuracy and efficiency of prediction and identification are improved using method of the invention.
Detailed description of the invention
By reference to the following drawings, exemplary embodiments of the present invention can be more fully understood by:
Fig. 1 is the flow chart according to the commutation failure prediction technique 100 of multifactor impact the considerations of embodiment of the present invention；
Fig. 2 is the valve current waveform figure according to embodiment of the present invention；
Fig. 3 is the logic chart that commutation failure prediction is carried out based on commutation failure value-at-risk according to embodiment of the present invention；
Fig. 4 is total logic chart according to the carry out phase conversion failure judgment of embodiment of the present invention；And
Fig. 5 is to be shown according to the structure of the commutation failure forecasting system 500 of multifactor impact the considerations of embodiment of the present invention
It is intended to.
Specific embodiment
Exemplary embodiments of the present invention are introduced referring now to the drawings, however, the present invention can use many different shapes
Formula is implemented, and is not limited to the embodiment described herein, and to provide these embodiments be at large and fully disclose
The present invention, and the scope of the present invention is sufficiently conveyed to person of ordinary skill in the field.Show for what is be illustrated in the accompanying drawings
Term in example property embodiment is not limitation of the invention.In the accompanying drawings, identical cells/elements use identical attached
Icon note.
Unless otherwise indicated, term (including scientific and technical terminology) used herein has person of ordinary skill in the field
It is common to understand meaning.Further it will be understood that with the term that usually used dictionary limits, should be understood as and its
The context of related fields has consistent meaning, and is not construed as Utopian or too formal meaning.
Fig. 1 is the flow chart according to the commutation failure prediction technique 100 of multifactor impact the considerations of embodiment of the present invention.
As shown in Figure 1, the commutation failure prediction technique of the considerations of embodiments of the present invention provide multifactor impact, it is contemplated that a variety of to lead
Cause the impact factor of commutation failure, it is determined that commutation failure risk criterion, and the commutation failure risk determined according to these factors
Commutation failure has occurred right and is predicted for value and commutation failure risk criterion；Side can be exchanged according to converter station when commutation failure
The transient characterisitics at the phase angle of electric current can identify whether that commutation failure has occurred well；Meanwhile utilizing method of the invention
Improve the accuracy and efficiency of prediction and identification.The commutation failure of the considerations of embodiments of the present invention provide multifactor impact
Prediction technique 100 calculates the value of each impact factor since step 101 place, in step 101；Wherein, the impact factor packet
It includes: at least two in the commutation voltage factor, harmonic factor, the DC current factor, valve current factor and the trigger pulse factor.
Preferably, wherein the value for calculating each impact factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1It opens
Begin to calculate, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve
When the absolute value of electric current is less than preset valve electric current threshold value；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome from 0
Pmin, maintain to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is big
In preset valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electricity
When flowing threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy
PminBecome Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor harmonic factor
Value；V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Electric current；PIvFor the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
Because commutation voltage mutation, DC current mutation, harmonic component is excessively high, valve current break and loses trigger pulse
It will lead to commutation failure, therefore commutation failure risks and assumptions consider these risk amounts, preferably to react commutation failure
Risk.In the embodiment of invention, the change of current busbar voltage U of converter station is acquiredL, DC current IdAnd valve electric current IV, then
Calculate the value of each impact factor.Specifically, comprising: the Sudden Changing Rate by calculating change of current busbar voltage defines the commutation voltage factor
Commutation voltage fundamental wave virtual value V is obtained by all-wave Fourier transformation1rmsAnd h subharmonic virtual value VhrmsContent,
Define harmonic factor
Sudden Changing Rate by calculating DC current defines the DC current factor
Second dervative by calculating valve electric current defines valve current factor
By the way that when loss trigger pulse makes the valve of the conducting and do not turn on, the valve electric current zero potential of defective valves is much big
In the characterizing definition trigger pulse factor P of valve current zero potential time under normal circumstancespulse。
In valve current waveform in an ideal case, in a valve current cycle, there are the zero potential areas of Time constant
Domain, the zero potential region be valve electric current absolute value be less than preset valve electric current threshold value the case where, as in Fig. 2 AB and
Shown in CD sections.The time of AB and CD be in the ideal case it is absolute identical, to AB sections after valve current sample and CD sections
Sampled point number is also identical, this is because what the rule of valve current cycle determined.I.e. if valve electric current a cycle 20ms, AB
Section is 5ms with CD sections, and sample frequency is set as 10 point/ms, then AB and CD sections is 50 points, the i.e. number of n.
In embodiments of the present invention, P is setpulseInitial value be 0, preset valve electric current threshold value be valve electric current manage
1.3 times of zero potential section valve current absolute value maximum value in the case of thinking.
In A point, the absolute value of current valve electric current Iv is less than preset valve electric current threshold value, and program starts to calculate, should
Sampled point is m1Point；Under normal circumstances, sampled point m1The absolute value of Iv when+n-1 should be again smaller than preset valve electric current threshold
Value, and the absolute value of valve electric current when sampled point m1+n then starts to be greater than preset valve electric current threshold value.But due to practical feelings
AB and CD of time has small fluctuation under condition, has stayed the nargin of 2 points at this time.
In sampled point m1When+n+1, if the absolute value of Iv is greater than preset valve electric current threshold value, P is still maintainedpulse
For zero output, when until the absolute value of valve electric current is less than preset valve electric current threshold value, i.e. C point.
If sampled point m1Detect that the absolute value of Iv is less than preset valve electric current threshold value when+n+1, it is believed that converter valve
Possible pulsing is lost, at this time PpulseOutput becomes P from 0min, and continue to test.In sampled point m1+ n+0.5n is detected again；
If including: sampled point m1The absolute value of Iv is greater than preset valve electric current threshold value when+n+0.5n, then PpulseBy PminBecome 0,
Until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value, i.e. C point；If sampled point m1When+n+0.5n
The absolute value of valve electric current is less than preset valve electric current threshold value, then PpulseBy PminBecome Pmax, until detecting the exhausted of valve electric current
When being less than preset valve electric current threshold value to value, i.e. C point.After reaching C point, C point is denoted as m1, re-start next valve electric current
The detection in period.
In step 102, changed according to the value of each impact factor and the calculating of the commutation failure influence degree of the impact factor
Phase risk of failure value.
Preferably, wherein it is described according to the value of each impact factor and the commutation failure influence degree meter of the impact factor
Calculate commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th
The value of a impact factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
Preferably, wherein determining the commutation failure influence degree of each impact factor using such as under type:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor preset i-th of impact factor
Commutation failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th
The value of a impact factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor preset i-th of impact factor
Value maximum value.
In embodiments of the present invention, pass through the commutation failure influence degree factor C of each impact factor of definitioni, meter
Calculate commutation failure risks and assumptions Pcf, comprising:
Wherein, PcfFor commutation failure value-at-risk；The value of the commutation voltage factor；C1For the commutation failure of the commutation voltage factor
Influence degree；PhFor the value of harmonic factor；C2For the commutation failure influence degree of harmonic factor；For the DC current factor
Value；C3For the commutation failure influence degree of the DC current factor；PIvFor the value of valve current factor；C4For the commutation of valve current factor
Failure influence degree；PpulseFor the value of the trigger pulse factor；C5For the commutation failure influence degree of the trigger pulse factor.
Wherein, the corresponding shadow of different impact factors is arranged by influence degree of each impact factor to commutation risk of failure
The high and low risk definite value of the degree of sound.Wherein, the commutation failure influence degree of each impact factor is determined using such as under type:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor preset i-th of impact factor
Commutation failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th
The value of a impact factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor preset i-th of impact factor
Value maximum value.
In step 103, the commutation failure value-at-risk is compared with preset commutation failure risk criterion, with exchange
Whether stream station, which has occurred commutation failure, is predicted.
Preferably, wherein the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation does not occur for prediction result instruction converter station
Failure；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and it is fixed to be less than preset outlet
Value, then commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result indicates converter station meeting
Commutation failure occurs.
Preferably, wherein the method also includes:
When commutation failure may occur for prediction result instruction converter station, the electric current phase of the converter station exchange side of acquisition is calculated
The integrated value of the absolute value of the derivative of parallactic angle, and when the integrated value is less than 0, determine that commutation failure has occurred for converter station.
In embodiments of the present invention, pass through the starting definite value f of setting commutation failure riskqdWith outlet definite value fckIt does
For commutation failure risk criterion, determined with the risk to commutation failure, commutation failure risk criterion are as follows:
That is, if the commutation failure value-at-risk PcfLess than preset starting definite value fqd, then prediction result indicates converter station not
Commutation failure occurs；
If the commutation failure value-at-risk PcfMore than or equal to the preset starting definite value fqd, and be less than it is preset go out
Mouth definite value fck, then commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk PcfMore than or equal to the preset outlet definite value fck, then prediction result indicates to change
It flows standing-meeting and commutation failure occurs.
When meeting fqd≤Pcf< fckWhen, it is believed that commutation failure may occur, continue phase-detection, acquire converter station
Ac-side current phase angle θ calculates the integral derivative at phase angleAs phase-detection criterion, whenWhen,
Think that commutation failure has occurred.
When meeting Pcf≥fqdWhen, it is believed that commutation failure can occur, detectingWhen, it is believed that commutation has occurred
Failure.
It can judge that commutation is lost well according to the transient characterisitics at the phase angle of converter station ac-side current when commutation failure
It loses and whether occurs.
Fig. 3 is the logic chart that commutation failure prediction is carried out based on commutation failure value-at-risk according to embodiment of the present invention.
As shown in figure 3, logical relation includes: the value P for calculating each impact factorjCommutation failure corresponding with the impact factor influences journey
Spend Ci；According to PjAnd CiCalculate commutation failure value-at-risk Pcf；And judged according to commutation failure risk criterion, it is determined whether
Commutation failure occurs.
Fig. 4 is total logic chart according to the carry out phase conversion failure judgment of embodiment of the present invention.As shown in figure 4, in this hair
In bright embodiment, it is determined whether it includes: to be judged according to commutation failure risk criterion or changed according to conventional that commutation failure, which occurs,
Mutually failure criterion judgement, wherein change of current voltage factor, harmonic factor, the DC current factor, valve electricity are determined according to converter station information
The factor and the trigger pulse factor are flowed, and is calculated according to the value of each impact factor, to judge whether to meet commutation failure risk
Criterion.
In embodiments of the present invention, it predicts and is confirmed whether that commutation failure, which occurs, includes:
(1) when single phase metal failure occurs for AC-DC hybrid power grid DC converter station exchange side outlet, the change of current is acquired
The change of current busbar voltage U to standL, DC current IdAnd valve electric current IV；
(2) value of the commutation voltage factor is calculatedThe value P of harmonic factorh, the DC current factor valueValve electric current because
The value P of sonIvWith the value P of the trigger pulse factorpulse；
(3) whether it is more than corresponding risk definite value according to each impact factor, determines the corresponding influence degree of each impact factor
Ci；
(4) according to the value of each impact factor and corresponding influence degree CiCalculate commutation failure value-at-risk Pcf；
(6) 0.1ms after failure occurs, judges Pcf≥fqd, therefore prediction has the risk that commutation failure occurs, and carries out
Phase-detection starting；
(7) 0.2ms after failure occurs, interpretation go out Pcf≥fck, therefore commutation failure will occur for prediction；
(8) commutation failure occurs for 1ms after failure occurs, adjacent direct current system；
(9) 0.2ms after commutation failure occurs, judgesThus identify that commutation failure.
Fig. 5 is to be shown according to the structure of the commutation failure forecasting system 500 of multifactor impact the considerations of embodiment of the present invention
It is intended to.As shown in figure 5, the commutation failure forecasting system 500 of the considerations of embodiments of the present invention provide multifactor impact, packet
It includes: value computing unit 501, commutation failure value-at-risk computing unit 502 and the commutation failure predicting unit 503 of impact factor.
Preferably, the value computing unit 501 of the impact factor, for calculating the value of each impact factor；Wherein, described
Impact factor includes: in the commutation voltage factor, harmonic factor, the DC current factor, valve current factor and the trigger pulse factor
At least two.
Preferably, wherein the value computing unit 501 of the impact factor, calculates the value of each impact factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1It opens
Begin to calculate, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve
When the absolute value of electric current is less than preset valve electric current threshold value；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome from 0
Pmin, maintain to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is big
In preset valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electricity
When flowing threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy
PminBecome Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor harmonic factor
Value；V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Electric current；PIvFor the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
Preferably, the commutation failure value-at-risk computing unit 502, for the value and the shadow according to each impact factor
The commutation failure influence degree for ringing the factor calculates commutation failure value-at-risk.
Preferably, wherein the commutation failure value-at-risk computing unit 502, according to the value of each impact factor and the shadow
The commutation failure influence degree for ringing the factor calculates commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th
The value of a impact factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
Preferably, wherein determining the commutation failure influence degree of each impact factor using such as under type:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor preset i-th of impact factor
Commutation failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th
The value of a impact factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor preset i-th of impact factor
Value maximum value.
Preferably, the commutation failure predicting unit 503, for losing the commutation failure value-at-risk and preset commutation
It loses risk criterion to be compared, to predict whether converter station has occurred commutation failure.
Preferably, wherein the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation does not occur for prediction result instruction converter station
Failure；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and it is fixed to be less than preset outlet
Value, then commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result indicates converter station meeting
Commutation failure occurs.
Preferably, wherein the system also includes commutation failure recognition unit, for can when prediction result instruction converter station
When commutation failure can occur, the integrated value of the absolute value of the derivative of the current phase angle of the converter station exchange side of acquisition is calculated, and
When the integrated value is less than 0, determine that commutation failure has occurred for converter station.
The considerations of the embodiment of the present invention multifactor impact commutation failure forecasting system 500 and another reality of the invention
The commutation failure prediction technique 100 of the considerations of applying multifactor impact is corresponding, and details are not described herein.
The present invention is described by reference to a small amount of embodiment.However, it is known in those skilled in the art, as
Defined by subsidiary Patent right requirement, in addition to the present invention other embodiments disclosed above equally fall in it is of the invention
In range.
Normally, all terms used in the claims are all solved according to them in the common meaning of technical field
It releases, unless in addition clearly being defined wherein.All references " one/described/be somebody's turn to do [device, component etc.] " are all opened ground
At least one example being construed in described device, component etc., unless otherwise expressly specified.Any method disclosed herein
Step need not all be run with disclosed accurate sequence, unless explicitly stated otherwise.
Claims (12)
1. a kind of commutation failure prediction technique for considering multifactor impact, which is characterized in that the described method includes:
Calculate the value of each impact factor；Wherein, the impact factor includes: the commutation voltage factor, harmonic factor, DC current
At least two in the factor, valve current factor and the trigger pulse factor；
Commutation failure value-at-risk is calculated according to the value of each impact factor and the commutation failure influence degree of the impact factor；
The commutation failure value-at-risk is compared with preset commutation failure risk criterion, whether converter station has occurred
Commutation failure is predicted.
2. the method according to claim 1, wherein the value for calculating each impact factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1Start to count
It calculates, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve electric current
Absolute value be less than preset valve electric current threshold value when；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome P from 0min,
It maintains to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is greater than pre-
If valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electric current door
When threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy Pmin
Become Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor the value of harmonic factor；
V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Stream；For the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
3. the method according to claim 1, wherein the value according to each impact factor and the influence because
The commutation failure influence degree of son calculates commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th of shadow
Ring the value of the factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
4. the method according to claim 1, wherein determining that the commutation of each impact factor is lost using such as under type
Lose influence degree:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor the commutation of preset i-th of impact factor
Failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th of shadow
Ring the value of the factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor the value of preset i-th of impact factor
Maximum value.
5. the method according to claim 1, wherein the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation mistake does not occur for prediction result instruction converter station
It loses；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and is less than preset outlet definite value, then
Commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result instruction converter station can occur
Commutation failure.
6. according to the method described in claim 5, it is characterized in that, the method also includes:
When commutation failure may occur for prediction result instruction converter station, the current phase angle of the converter station exchange side of acquisition is calculated
The integrated value of absolute value of derivative determine that commutation failure has occurred for converter station and when the integrated value is less than 0.
7. a kind of commutation failure forecasting system for considering multifactor impact, which is characterized in that the system comprises:
The value computing unit of impact factor, for calculating the value of each impact factor；Wherein, the impact factor includes: commutation
At least two in voltage factor, harmonic factor, the DC current factor, valve current factor and the trigger pulse factor；
Commutation failure value-at-risk computing unit, for according to the value of each impact factor and the commutation failure shadow of the impact factor
The degree of sound calculates commutation failure value-at-risk；
Commutation failure predicting unit, for comparing the commutation failure value-at-risk and preset commutation failure risk criterion
Compared with to predict whether converter station has occurred commutation failure.
8. system according to claim 7, which is characterized in that the value computing unit of the impact factor calculates each shadow
Ring the value of the factor, comprising:
When impact factor is commutation voltage because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is harmonic factor,
When impact factor is DC current because of the period of the day from 11 p.m. to 1 a.m,
When impact factor is valve current factor,
When impact factor be trigger pulse because of the period of the day from 11 p.m. to 1 a.m, determine P using such as under typepulse, include:
In a valve current cycle, the sampled point m of preset valve electric current threshold value is less than from the absolute value of valve electric current1Start to count
It calculates, if sampled point m1The absolute value of valve electric current when+n+1 is greater than preset valve electric current threshold value, then PpulseFor 0 until valve electric current
Absolute value be less than preset valve electric current threshold value when；
If sampled point m1The absolute value of valve electric current when+n+1 is less than preset valve electric current threshold value, then PpulseBecome P from 0min,
It maintains to sampled point m1P is redefined when+n+0.5npulse；If sampled point m1The absolute value of valve electric current when+n+0.5n is greater than pre-
If valve electric current threshold value, then PpulseBy PminBecome 0, until detecting that the absolute value of valve electric current is less than preset valve electric current door
When threshold value；If sampled point m1The absolute value of valve electric current when+n+0.5n is less than preset valve electric current threshold value, then PpulseBy Pmin
Become Pmax, until when detecting that the absolute value of valve electric current is less than preset valve electric current threshold value；
Wherein,The value of the commutation voltage factor；ULFor the change of current busbar voltage of the converter station of acquisition；PhFor the value of harmonic factor；
V1rmsFor commutation voltage fundamental wave virtual value；VhrmsFor h subharmonic virtual value；For the value of the DC current factor；IdFor direct current
Stream；For the value of valve current factor；IVFor valve electric current；PpulseFor the value of the trigger pulse factor；PminFor preset trigger pulse
Factor minimum value；PmaxFor preset trigger pulse factor maximum value；m1To detect that the absolute value of valve electric current is less than preset door
The sampled point of threshold value；N is that the absolute value of normal condition lower valve electric current is less than the number of sampling points of preset threshold value.
9. system according to claim 7, which is characterized in that the commutation failure value-at-risk computing unit, according to each
The value of impact factor and the commutation failure influence degree of the impact factor calculate commutation failure value-at-risk, comprising:
Wherein, PcfFor the commutation failure value-at-risk；CiFor the commutation failure influence degree of i-th of impact factor；PiI-th of shadow
Ring the value of the factor；N is the number of impact factor；Positive integer of the value range of i between [1, N].
10. system according to claim 7, which is characterized in that determine the commutation of each impact factor using such as under type
Failure influence degree:
Wherein, CiFor the commutation failure influence degree of i-th of impact factor；Ci_lowFor the commutation of preset i-th of impact factor
Failure influence degree minimum value；Ci_maxThe commutation failure influence degree maximum value of preset i-th of impact factor；PiI-th of shadow
Ring the value of the factor；PiminFor the minimum value of the value of preset i-th of impact factor；PimaxFor the value of preset i-th of impact factor
Maximum value.
11. system according to claim 7, which is characterized in that the preset commutation failure risk criterion, comprising:
If the commutation failure value-at-risk is less than preset starting definite value, commutation mistake does not occur for prediction result instruction converter station
It loses；
If the commutation failure value-at-risk is more than or equal to the preset starting definite value, and is less than preset outlet definite value, then
Commutation failure may occur for prediction result instruction converter station；
If the commutation failure value-at-risk is more than or equal to the preset outlet definite value, prediction result instruction converter station can occur
Commutation failure.
12. system according to claim 11, which is characterized in that the system also includes:
Commutation failure recognition unit, for calculating changing for acquisition when commutation failure may occur for prediction result instruction converter station
The integrated value of the absolute value of the derivative of the current phase angle of stream station exchange side, and when the integrated value is less than 0, determine converter station
Commutation failure has occurred.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111781453A (en) * | 2020-07-04 | 2020-10-16 | 国家电网公司华中分部 | Fault moment-based direct current system commutation failure risk assessment method |
| CN112510744A (en) * | 2020-04-30 | 2021-03-16 | 中国电力科学研究院有限公司 | Method and system for inhibiting commutation failure |
| WO2021143793A1 (en) * | 2020-01-19 | 2021-07-22 | 华南理工大学 | Commutation failure protection method and apparatus, computer device, and storage medium |
| CN113484578A (en) * | 2021-07-14 | 2021-10-08 | 南方电网科学研究院有限责任公司 | Commutation state detection method, device and equipment of high-voltage direct current system |
| WO2022148074A1 (en) * | 2021-01-06 | 2022-07-14 | 华南理工大学 | Method for solving for converter valve states and valve currents based on valve-side current timing characteristics |
| CN116184123A (en) * | 2023-04-21 | 2023-05-30 | 山东大学 | Commutation failure judging method based on commutation failure recognition factor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103488883A (en) * | 2013-09-11 | 2014-01-01 | 国家电网公司 | Commutation failure monitoring method for high-voltage direct-current transmission converter valves |
| KR20150142763A (en) * | 2014-06-11 | 2015-12-23 | 한국전력공사 | Apparatus for predicting and controlling commutation failure of high voltage direct current system |
-
2019
- 2019-07-03 CN CN201910595078.5A patent/CN110323773B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103488883A (en) * | 2013-09-11 | 2014-01-01 | 国家电网公司 | Commutation failure monitoring method for high-voltage direct-current transmission converter valves |
| KR20150142763A (en) * | 2014-06-11 | 2015-12-23 | 한국전력공사 | Apparatus for predicting and controlling commutation failure of high voltage direct current system |
Non-Patent Citations (1)
| Title |
|---|
| 汤奕 等: "高压直流输电系统换相失败影响因素研究综述", 《中国电机工程学报》 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021143793A1 (en) * | 2020-01-19 | 2021-07-22 | 华南理工大学 | Commutation failure protection method and apparatus, computer device, and storage medium |
| CN112510744A (en) * | 2020-04-30 | 2021-03-16 | 中国电力科学研究院有限公司 | Method and system for inhibiting commutation failure |
| CN111781453A (en) * | 2020-07-04 | 2020-10-16 | 国家电网公司华中分部 | Fault moment-based direct current system commutation failure risk assessment method |
| CN111781453B (en) * | 2020-07-04 | 2022-07-29 | 国家电网公司华中分部 | Fault moment-based direct current system commutation failure risk assessment method |
| WO2022148074A1 (en) * | 2021-01-06 | 2022-07-14 | 华南理工大学 | Method for solving for converter valve states and valve currents based on valve-side current timing characteristics |
| US20230396143A1 (en) * | 2021-01-06 | 2023-12-07 | South China University Of Technology | Method For Solving For Converter Valve States And Valve Currents Based On Valve-Side Current Timing Characteristics |
| CN113484578A (en) * | 2021-07-14 | 2021-10-08 | 南方电网科学研究院有限责任公司 | Commutation state detection method, device and equipment of high-voltage direct current system |
| CN113484578B (en) * | 2021-07-14 | 2024-01-23 | 南方电网科学研究院有限责任公司 | Commutation state detection method, device and equipment for high-voltage direct-current system |
| CN116184123A (en) * | 2023-04-21 | 2023-05-30 | 山东大学 | Commutation failure judging method based on commutation failure recognition factor |
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