CN109752625A - High-voltage direct-current commutation failure detection method and device based on current conversion transformer side current - Google Patents
High-voltage direct-current commutation failure detection method and device based on current conversion transformer side current Download PDFInfo
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Abstract
The application discloses high-voltage direct-current commutation failure detection method based on current conversion transformer side current, which comprises the following steps: acquiring the waveform of current at the valve side of the converter transformer; and comparing the waveform with the waveform of the current on the valve side of the converter transformer of the converter valve in the normal operation state to judge whether the converter valve has phase conversion failure. Obviously, compared with the prior art, the method in the application can avoid the situation that whether the converter valve has phase change failure or not can be accurately detected only by depending on the current zero crossing point of the converter valve. In addition, in the application, because the waveform of the current on the valve side of the converter transformer can intuitively and accurately reflect the fault characteristics of the commutation failure, whether the commutation failure occurs to the converter valve is judged by using the waveform of the current on the valve side of the converter transformer, and the accuracy of the commutation failure detection result can be improved. Correspondingly, the high-voltage direct-current commutation failure detection device, medium and equipment based on the current at the valve side of the converter transformer disclosed by the application also have the beneficial effects.
Description
Technical field
The present invention relates to technical field of electric power, in particular to a kind of high voltage direct current commutation based on converter transformer valve side electric current is lost
Lose detection method, device, medium and equipment.
Background technique
Commutation failure refers to when two valves of inverter carry out commutation, finishes because commutation process not can be carried out, or pre-
Count shutdown valve breakdown after, fail during backward voltage restore blocking ability, when the voltage being added on the valve be timing, immediately
Again it is connected, then has occurred and switch phase, turn off the estimated valve opened again.If commutation failure has occurred in inverter, transmission of electricity
The transmission power of system will reduce, if failing in time to detected commutation failure, it will influence the safety of transmission system
Stable operation.
Currently, be usually to detect converter valve using converter valve current zero-crossing point whether to occur commutation failure, and high straightening
Many converter valves cannot provide zero crossing in stream engineering, cannot achieve the real-time detection to commutation failure.It can be seen that how to mention
For a kind of detection method of high voltage direct current commutation failure independent of converter valve current zero-crossing point, be those skilled in the art urgently
Problem to be solved.
Summary of the invention
In view of this, the purpose of the present invention is to provide a kind of high voltage direct current commutation failures based on converter transformer valve side electric current
Detection method, device, medium and equipment, to avoid that must rely on whether converter valve current zero-crossing point accurately could detect converter valve
Commutation failure occurs.Its concrete scheme is as follows:
A kind of high voltage direct current commutation failure detection method based on converter transformer valve side electric current, comprising:
Obtain the waveform of converter transformer valve-side electric current；
The waveform of converter transformer valve-side electric current by the waveform with converter valve under normal operation is compared,
To determine whether the converter valve occurs commutation failure.
Preferably, the process of the waveform for obtaining converter transformer valve-side electric current, comprising:
Obtain the target waveform when converter transformer valve-side electric current is negative value；
Correspondingly, the wave of the converter transformer valve-side electric current by the waveform and converter valve under normal operation
Shape is compared, to determine whether the converter valve occurs the process of commutation failure, comprising:
Judge the target waveform with the presence or absence of an increasing trend；
If so, judging whether an increasing trend is greater than the first preset threshold；
If so, judging the target waveform with the presence or absence of maximum；
If so, whether the decline trend of the target waveform is big after judging that the target waveform reaches the maximum
In the second preset threshold；
If so, determining the converter transformer valve-side electric current, there are the first commutation failure features；
Judge the target waveform with the presence or absence of increasing trend twice；
If so, whether the judgement increasing trend twice is greater than third predetermined threshold value；
If so, whether the judgement incremental spacing time of increasing trend twice is less than the converter valve and is running well
The incremental spacing time of the increasing trend twice of the converter transformer valve-side electric current under state；
It is passed if so, judging whether the target waveform exists after the increasing trend twice in preset time threshold
Subtract trend；
If so, determining the converter transformer valve-side electric current, there are the second commutation failure features；
Judge that the target waveform is special with the presence or absence of the first commutation failure feature and/or second commutation failure
Sign；
If so, determining that the commutation failure occurs for the converter valve.
Preferably, further includes:
Any one phase current of converter transformer valve-side is detected with the presence or absence of the first commutation failure feature and/or described the
Two commutation failure features；
If so, determining that the commutation failure occurs for inverter.
Preferably, further includes:
When the converter transformer valve-side electric current is negative value, the first signal is exported；
When an increasing trend is greater than first preset threshold, second signal is exported；
It detects first signal and whether the second signal exists；
If so, output third signal；
When the target waveform is there are when the maximum, fourth signal is exported；
After the target waveform reaches the maximum, it is default that the decline trend of the target waveform is greater than described second
When threshold value, the 5th signal is exported；
Detect whether the third signal, fourth signal and the 5th signal exist；
If so, determining the converter transformer valve-side electric current, there are the first commutation failure features.
Preferably, first signal, the second signal, the third signal, the fourth signal and the described 5th
Signal is level signal.
Preferably, further includes:
Using logic gates detect first signal and/or the second signal and/or the third signal and/or
The fourth signal and/or the 5th signal whether there is.
Preferably, further includes:
When increasing trend is greater than the third predetermined threshold value twice described in the target waveform, the 6th signal is exported；
In the presence of first signal and the 6th signal are equal, the 7th signal is exported；
When the incremental spacing time of the increasing trend twice is less than, the converter valve is described under normal operation to be changed
When the incremental spacing time of the increasing trend twice of the waveform of convertor transformer current on valve side, the 8th signal is exported；
When the 6th signal, the 7th signal and the 8th signal it is equal in the presence of, export the 9th signal；
Start to pass described in presentation in the preset time threshold after target waveform is in the increasing trend twice
Subtract trend, exports the tenth signal；
In the presence of the 9th signal and the tenth signal are equal, then determine that the converter transformer valve-side electric current exists
The second commutation failure feature.
Correspondingly, the invention also discloses a kind of, the high voltage direct current commutation failure based on converter transformer valve side electric current detects dress
It sets, comprising:
Waveform obtains module, for obtaining the waveform of converter transformer valve-side electric current；
Waveform comparison module, for the converter transformer valve-side electricity by the waveform and converter valve under normal operation
The waveform of stream is compared, to determine whether the converter valve occurs commutation failure.
Correspondingly, the invention also discloses a kind of computer readable storage mediums, which is characterized in that described computer-readable
It is stored with computer program on storage medium, is realized when the computer program is executed by processor and is based on changing as previously disclosed
The step of high voltage direct current commutation failure detection method of rheology current on valve side.
Correspondingly, the invention also discloses a kind of, the high voltage direct current commutation failure detection based on converter transformer valve side electric current is set
It is standby, comprising:
Memory, for storing computer program；
Processor realizes the height as previously disclosed based on converter transformer valve side electric current when for executing the computer program
The step of straightening stream commutation failure detection method.
As it can be seen that being then the waveform of acquisition converter transformer valve-side electric current utilizes what is got first in the present invention
The waveform of converter transformer valve-side electric current of the waveform with converter valve under normal operation is compared, and judges the change of current with this
Whether valve occurs commutation failure.Obviously, compared with the prior art, through the invention in method, converter valve can be avoided relying on
Current zero-crossing point could accurately detect whether converter valve occurs commutation failure.Moreover, in the present invention, because of converter transformer valve
The waveform of side electric current can intuitive, reflection commutation failure accurately fault signature, so, utilize converter transformer valve-side electricity
The waveform of stream judges whether converter valve occurs commutation failure, can be improved the accuracy of commutation failure testing result.Correspondingly,
A kind of high voltage direct current commutation failure detection device, medium and equipment based on converter transformer valve side electric current disclosed by the invention, equally
With above-mentioned beneficial effect.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
The embodiment of invention for those of ordinary skill in the art without creative efforts, can also basis
The attached drawing of offer obtains other attached drawings.
Fig. 1 is a kind of high voltage direct current commutation failure detection side based on converter transformer valve side electric current provided in an embodiment of the present invention
The flow chart of method；
Fig. 2 is another high voltage direct current commutation failure detection based on converter transformer valve side electric current provided in an embodiment of the present invention
The flow chart of method；
Fig. 3 is that there are the signals of the first commutation failure feature for converter transformer valve-side electric current provided in an embodiment of the present invention
Figure；
Fig. 4 is that there are the signals of the second commutation failure feature for converter transformer valve-side electric current provided in an embodiment of the present invention
Figure；
Fig. 5 is that judgement converter transformer valve-side electric current provided in an embodiment of the present invention whether there is the first commutation failure feature
Method flow diagram；
Fig. 6 sentences converter power transformer current on valve side the first commutation failure feature progress logic to be provided in an embodiment of the present invention
Disconnected schematic diagram；
Fig. 7 is that judgement converter transformer valve-side electric current provided in an embodiment of the present invention whether there is the second commutation failure feature
Method flow diagram；
Fig. 8 sentences converter power transformer current on valve side the second commutation failure feature progress logic to be provided in an embodiment of the present invention
Disconnected schematic diagram；
Fig. 9 is the schematic diagram that single-phase current on valve side commutation failure provided in an embodiment of the present invention detects logic；
Figure 10 is the schematic diagram that inverter commutation failure provided in an embodiment of the present invention detects logic；
Figure 11 is the schematic diagram of direct current transportation fault setting provided in an embodiment of the present invention；
Inverter side AC and DC voltage and valve current waveform when Figure 12 is generation commutation failure provided in an embodiment of the present invention
Schematic diagram；
Inverter side converter transformer valve-side current waveform when Figure 13 is generation commutation failure provided in an embodiment of the present invention
Schematic diagram；
Figure 14 is the commutation failure testing result provided in an embodiment of the present invention based on converter transformer valve-side current characteristic
Schematic diagram；
Figure 15 is a kind of high voltage direct current commutation failure inspection based on converter transformer valve side electric current provided by the embodiment of the present invention
Survey the structure chart of device；
Figure 16 is a kind of high voltage direct current commutation failure inspection based on converter transformer valve side electric current provided by the embodiment of the present invention
The structure chart of measurement equipment.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
As shown in Figure 1, the embodiment of the invention discloses a kind of high voltage direct current commutation failures based on converter transformer valve side electric current
Detection method, this method comprises:
Step S11: the waveform of converter transformer valve-side electric current is obtained；
Step S12: the waveform of the converter transformer valve-side electric current of waveform and converter valve under normal operation is carried out
Compare, to determine whether converter valve occurs commutation failure.
In practical application, commutation failure is one of higher failure of DC transmission system probability of happening, commutation failure
The main reason for be because of fault in ac transmission system so that inverter side change of current busbar voltage declines, under certain conditions, some commutations
Failure can restore automatically, and still, if converter valve recurs twice or repeatedly, commutation failure, converter valve will be latched,
To interrupt the passway for transmitting electricity of direct current system, in severe case, it is possible that commutation failure occurs simultaneously for multiple Inverter Stations
The phenomenon that, even result in mains breakdown.
It in the present embodiment, is to obtain converter transformer valve-side first in order to judge whether converter valve occurs commutation failure
The waveform of electric current, obtain converter transformer valve-side electric current waveform during, can be obtain current on valve side from negative value to
The waveform of positive value variation is also possible to obtain the waveform that current on valve side changes from positive value to negative value, as long as the change of current can be represented
The variation tendency of transformer current on valve side.
Then, waveform and converter valve the changing under normal operation of the converter transformer valve-side electric current got are utilized
The waveform of convertor transformer current on valve side is compared, and judges whether converter valve occurs commutation failure with this.It is understood that
It is that the waveform and converter valve of converter transformer valve-side electric current of the converter valve under normal operation are changed when commutation failure occurs
The waveform of convertor transformer current on valve side can show different variation tendencies, such as: when commutation failure occurs for converter valve, the change of current
Converter transformer valve-side electricity of the increasing trend of the waveform of transformer current on valve side compared to converter valve under normal operation
The increasing trend of the waveform of stream either decline trend can be more obvious, also, when commutation failure occurs for converter valve, the change of current becomes
The incremental spacing time of the increasing trend of the waveform of depressor current on valve side can also show different variations, so, according to these
Variation characteristic enough judges whether converter valve occurs commutation failure.
It is the waveform for obtaining converter transformer valve-side electric current first as it can be seen that in the present embodiment, then, using getting
The waveform of converter transformer valve-side electric current of the waveform with converter valve under normal operation be compared, judge to change with this
Whether stream valve occurs commutation failure.Obviously, compared with the prior art, through this embodiment in method, can avoid relying on and change
Stream valve current zero-crossing point could accurately detect whether converter valve occurs commutation failure.Moreover, in the present embodiment, because the change of current becomes
The waveform of depressor current on valve side can intuitive, reflection commutation failure accurately fault signature, so, utilize converter power transformer
The waveform of current on valve side judges whether converter valve occurs commutation failure, can be improved the accuracy of commutation failure testing result.
Based on the above embodiment, the present embodiment is further described and optimizes to technical solution, as shown in Fig. 2, being this
The flow chart for another high voltage direct current commutation failure detection method based on converter transformer valve side electric current that embodiment provides.Specifically
, above-mentioned steps S11: obtain the process of the waveform of converter transformer valve-side electric current, comprising:
Step S111: target waveform when converter transformer valve-side electric current is negative value is obtained；
Correspondingly, step S12: by the wave of the converter transformer valve-side electric current of waveform and converter valve under normal operation
Shape is compared, to determine whether converter valve occurs the process of commutation failure, comprising:
Step S201: judge target waveform with the presence or absence of an increasing trend；
Step S202: if so, judging whether an increasing trend is greater than the first preset threshold；
Step S203: if so, judging target waveform with the presence or absence of maximum；
Step S204: if so, after judging that target waveform reaches maximum, whether the decline trend of target waveform is greater than the
Two preset thresholds；
Step S205: if so, determining converter transformer valve-side electric current, there are the first commutation failure features；
Step S206: judge target waveform with the presence or absence of increasing trend twice；
Step S207: if so, whether increasing trend is greater than third predetermined threshold value twice for judgement；
Step S208: it is normally being transported if so, judging whether the incremental spacing time of increasing trend is less than converter valve twice
Turn the incremental spacing time of the increasing trend twice of the waveform of the converter transformer valve-side electric current under state；
Step S209: if so, judging whether target waveform exists after increasing trend twice in preset time threshold
Decline trend；
Step S210: if so, determining converter transformer valve-side electric current, there are the second commutation failure features；
Step S211: judge target waveform with the presence or absence of the first commutation failure feature and/or the second commutation failure feature；
Step S212: if so, determining that commutation failure occurs for converter valve.
It in the present embodiment, is illustrated by taking target waveform when converter transformer valve-side electric current is negative value as an example,
That is, being to be illustrated to the target waveform of converter power transformer current on valve side from just becoming negative process.Specifically, in the present embodiment
In, be during judging whether converter valve occurs commutation failure, according to converter transformer valve-side electric current be negative value when mesh
The variation tendency of mark waveform summarizes two kinds of commutation failure features that commutation failure occurs for converter valve, that is, the first commutation failure
Feature and the second commutation failure feature.
As shown in figure 3, being that there are the waveform diagrams of the first commutation failure feature for converter transformer valve-side electric current.Such as Fig. 4
It is shown, it is that there are the waveform diagrams of the second commutation failure feature for converter transformer valve-side electric current.In Fig. 3, target waveform
An increasing trend be greater than the first preset threshold, target waveform there are maximum, also, after target waveform reaches maximum,
The decline trend of target waveform is greater than the second preset threshold, so, it is possible to determine that there are first to change for converter transformer valve-side electric current
Mutually failure feature.In Fig. 4, target waveform exist twice increasing trend, the incremental spacing time of increasing trend is less than twice
The incremental spacing time of the increasing trend twice of the waveform of converter transformer valve-side electric current of the converter valve under normal operation,
Also, in preset time threshold, there are decline trends after increasing trend twice for target waveform, so, it is possible to determine that the change of current becomes
There are the second commutation failure features for depressor current on valve side.In practical application, if there are the first commutation failures for target waveform
Feature, or there are the second commutation failure features, or exist simultaneously the first commutation failure feature and the second commutation failure
Feature then can be determined that commutation failure has occurred in converter valve.
It should be noted that in the present embodiment, the first preset threshold, third predetermined threshold value, is preset the second preset threshold
The incremental spacing time of time threshold and converter valve the current on valve side increasing trend twice under normal operation, is all basis
Artificial experience and pre-set numerical value, in practical application, these numerical value can make adaptability according to the actual situation
Adjustment.
Obviously, in the present embodiment, judge current on valve side with the presence or absence of the first commutation failure by multiple Rule of judgment
Feature and/or the second commutation failure feature, and by judge that target waveform whether there is the first commutation failure feature and/or the
Two commutation failure features, to judge whether converter valve occurs commutation failure, by multiple Rule of judgment successively come to target waveform
Judged, the judgement result of commutation failure can be made more accurate, reliable.
Based on the above embodiment, the present embodiment is further described and optimizes to technical solution.Specifically, above-mentioned commutation
Failure detection method further include:
Any one phase current of converter transformer valve-side is detected to lose with the presence or absence of the first commutation failure feature and/or the second commutation
Lose feature；
If so, determining that commutation failure occurs for inverter.
It is understood that multiple converter valves are provided in inverter, in practical application, if detecting converter valve
In any one phase current there are when the first commutation failure feature and/or the second commutation failure feature, then can be determined that inverter send out
Commutation failure is given birth to.
Obviously, by judge any one phase current of converter transformer valve-side with the presence or absence of the first commutation failure feature and/or
Second commutation failure feature, comes whether accurate judgement inverter occurs commutation failure, can avoid relying on converter valve current over-zero
Point could accurately detect whether converter valve occurs commutation failure.
Based on the above embodiment, the present embodiment is further described and optimizes to technical solution.As shown in figure 5, being this
A kind of judgement converter transformer valve-side that embodiment provides whether there is the method flow diagram of the first commutation failure feature.Specific packet
Include following steps:
Step S31: when converter transformer valve-side electric current is negative value, the first signal is exported；
Step S32: when an increasing trend is greater than the first preset threshold, second signal is exported；
Step S33: whether detection the first signal and the second signal exist；
Step S34: if so, output third signal；
Step S35: when target waveform is there are when maximum, fourth signal is exported；
Step S36: after target waveform reaches maximum, when the decline trend of target waveform is greater than the second preset threshold,
Export the 5th signal；
Step S37: whether detection third signal, fourth signal and the 5th signal exist；
Step S38: if so, determining converter transformer valve-side electric current, there are the first commutation failure features.
In the present embodiment, it is that converter transformer valve-side electric current is represented as negative value using the first signal, is represented with second signal
The increasing trend of target waveform is greater than the first preset threshold, represents the first signal and the second signal with third signal and exists simultaneously,
Representing target waveform with fourth signal, there are maximum, after representing target waveform arrival maximum with the 5th signal, target waveform
Decline trend be greater than the second preset threshold.Later, if detecting that third signal, fourth signal and the 5th signal exist simultaneously
When, then illustrating converter transformer valve-side electric current, there are the first commutation failure features.
Obviously, judge that converter transformer valve-side electric current, can with the presence or absence of the first commutation failure feature by output signal
So that the deterministic process of the first commutation failure feature is more intuitive, clear, so that the judgement of the first commutation failure feature
As a result more accurate, reliable.
As a preferred embodiment, the first signal, second signal, third signal, fourth signal and the 5th signal
It is level signal.
It is understood that level signal refers to that the signal indicated with level value, level value are divided into high level " 1 " and low electricity
Flat " 0 ".So being that the first signal, second signal, third signal, fourth signal and the 5th signal are arranged in the present embodiment
For level signal so that the first signal, second signal, third signal, fourth signal and the 5th signal signal exported
Cheng Gengwei is intuitive, clear.
As a preferred embodiment, detecting the first signal and/or second signal and/or the using logic gates
Three signals and/or fourth signal and/or the 5th signal whether there is.
It is understood that logic gates includes with door or door, NOT gate three classes basic logic gate circuit and by one
Or the complex logic gate circuit of multiple logic gates compositions can be to the first commutation by level signal and logic gates
Failure feature is more quickly and accurately detected, also, detects current on valve side with the presence or absence of first by logic gates
Commutation failure feature can make logic judgment result relatively sharp, clear.
As shown in fig. 6, being the schematic diagram for carrying out logic judgment to the first commutation failure feature.Specifically, first determining whether valve
Side electric current ijIt (n) whether is negative value, if so, obtaining judging result LIP(n), it maintains to current on valve side close to zero (Izero),
Wherein, IvsDC current negative value when to operate normally；Then, judge whether current on valve side is in increasing trend, also, be incremented by
Trend is greater than the first preset threshold Δ IincN, export judging result LincN(n), then with LIP(n) judgement knot is obtained through "AND" logic
Fruit LN(n)；Current on valve side is judged again with the presence or absence of maximum, if it is present judging result is Lmax(n)；Secondly, judging pole
Big value Lmax(n) whether current on valve side decline trend is greater than the Δ I of the second preset threshold afterwardsdecN, if so, output judging result
LdecN(n)；Finally, by LN(n) extend time t1Export LND(n), L is judged in conjunction with maximummax(n) and decline trend judges LdecN
(n), the judgement result L of the first commutation failure feature of final current on valve side is obtained after "AND" logicCFj-1(n).In Fig. 6
Control process it is specific as follows:
1) current on valve side is started to initial value i when being incremented bys(n) it maintains until being no longer incremented by, exports iL(n)；
Wherein, LincIt (n) is the high level signal of current on valve side increasing process output；Pinc-f(n) it is incremented by for current on valve side and opens
The pulse at moment beginning, that is, working as Linc(n) when becoming 1 from 0, Pinc-f(n) pulse that output amplitude is 1.
2) judge current on valve side ij(n) and iL(n) whether difference is greater than the first preset threshold Δ IincN, that is, judging valve side
Electric current ij(n) and iL(n) whether the first increasing trend is greater than the first preset threshold Δ IincN, if so, output high level, defeated
Signal is L outincN(n)；
3) judge current on valve side ij(n) whether it is less than DC current negative value I when operating normallyVS, if so, output LM
(n) it is high level, and maintains until current on valve side is increased close to zero, exports LIP(n)；Wherein, IzeroTo be approximately equal to zero
Constant value, then:
4) by the L of outputIP(n) and LincN(n) L is obtained through "AND" logicN(n), and through time delay process delay time t1, obtain
To signal LND(n)；
LND(n)=(LIP(n)·LincN(n))·delay(t1)；
Wherein, delay (t) is delay function, and f (t) is level signal, f (t) delay (t1) effect be by level
The each failing edge of signal f (t) delays t1Second.
5) initial value i when starting to successively decrease by current on valve sideT(n) it maintains until no longer successively decreasing, exports as ip(n)；
6) judge ip(n) with current on valve side ij(n) whether difference is greater than the second preset threshold Δ IdecN, that is, judgement judgement
ip(n) with current on valve side ij(n) whether decline trend is greater than the second preset threshold Δ IdecN, if so, output high level, defeated
Signal is L outdecN(n)；
7) finally by the L of outputdecN(n) and LND(n), maximum Lmax(n) it through "AND" logic, obtains valve side j phase current and changes
Mutually when failure, the first commutation failure feature testing result LCFj-1(n)；
LCFj_1(n)=LND(n)·LdecN(n)·Lmax(n)。
Based on the above embodiment, the present embodiment is further described and optimizes to technical solution.In the present embodiment, it is
A kind of method for judging converter transformer valve-side electric current with the presence or absence of the second commutation failure feature is provided, as shown in Figure 7.
Specifically includes the following steps:
Step S41: when the increasing trend twice of target waveform is greater than third predetermined threshold value, the 6th signal is exported；
Step S42: in the presence of the first signal and the 6th signal are equal, the 7th signal is exported；
Step S43: it is less than converter valve in normal operation lower valve side electricity when the incremental spacing time of increasing trend twice
When flowing the incremental spacing time of increasing trend twice, the 8th signal is exported；
Step S44: whether the 6th signal of detection, the 7th signal and the 8th signal exist；
Step S45: if so, the 9th signal of output；
Step S46: starting that decline trend is presented in preset time threshold after target waveform is in increasing trend twice, defeated
Tenth signal out；
Step S47: in the presence of the 9th signal and the tenth signal are equal, then determine that there are second for converter transformer valve-side electric current
Commutation failure feature.
It is understood that judging converter transformer valve-side electric current with the presence or absence of first in addition to can use output signal
Other than commutation failure feature, it can also judge that converter transformer valve-side electric current loses with the presence or absence of the second commutation using output signal
Lose feature.Specifically, being pre- greater than third come the increasing trend twice for representing target waveform with the 6th signal in the present embodiment
If threshold value, the first signal is represented with the 7th signal and the 6th signal exists simultaneously, target waveform is represented with the 8th signal and is passed twice
The incremental spacing time of increasing trend is less than the incremental spacing of converter valve current on valve side increasing trend twice under normal operation
Time represents the 6th signal, the 7th signal and the 8th signal with the 9th signal and exists simultaneously, and represents target waveform with the tenth signal
After increasing trend twice, target waveform starts that decline trend is presented in preset time threshold.Later, if detecting the 9th
Signal and the tenth signal exist simultaneously, then illustrating converter transformer valve-side electric current, there are the second commutation failure features.
It should be noted that in the present embodiment, the incremental spacing of third predetermined threshold value, target waveform increasing trend twice
Time, converter valve current on valve side the incremental spacing time of increasing trend and preset time threshold twice under normal operation
Value, is all pre-set numerical value according to artificial experience, in practical application, these numerical value can be according to the actual situation
Make the adjustment of adaptability.
Similarly, judge that converter transformer valve-side electric current, can with the presence or absence of the second commutation failure feature by output signal
So that the deterministic process of the second commutation failure feature is more effective, intuitive, so that the judgement of the second commutation failure feature
As a result more accurate, reliable.
As shown in figure 8, being the schematic diagram for carrying out logic judgment to the second commutation failure feature.Specifically, detecting valve first
Side electric current ij(n) with the presence or absence of increasing trend twice, also, increasing trend is greater than third predetermined threshold value Δ I twiceincD, output sentences
Disconnected result LincD(n)；Then, judge whether the incremental spacing time of increasing trend twice is less than converter valve in normal operation
The incremental spacing time T of lower current on valve side increasing trend twicec, judging result LB(n)；Current on valve side need to be guaranteed by bearing simultaneously
It is worth to positive value and is incremented by, i.e., by LincD(n) and LIP(n) after "AND" logic, then through t2Delay obtains LDP(n)；Again by LincD(n)、LB
(n) and LDP(n) L is obtained after "AND" logicD(n), it and maintains to terminate to second of increasing trend, obtains LDH(n)；Finally judge
After second of increasing trend, whether the waveform of current on valve side starts that decline trend is presented in preset time threshold, if so,
By LDH(n) delay time t3Afterwards, then with the judging result L that successively decreasesdecN(n) final current on valve side first is obtained after "AND" logic
The judgement result L of commutation failure featureCFj-2(n).Control process in Fig. 8 is specific as follows:
1) current on valve side is started to initial value i when being incremented byDS(n) it maintains until being no longer incremented by, exports as iDL(n)；
2) judge current on valve side ij(n) with signal iDL(n) whether difference is greater than third predetermined threshold value Δ IincD, that is, valve
Side electric current ij(n) whether the increasing trend twice of target waveform is greater than third predetermined threshold value, if so, output high level, defeated
Signal is L outincD(n)。
It should be noted that this step with judging target waveform, there are the mesh of the step 2) when the first commutation failure feature
It is different, that is, this step is not only detection current on valve side with the presence or absence of increasing trend, moreover, also to judge valve side electricity
Whether the target waveform of stream there is increasing trend twice, and the incremental amplitude, ao I setincDGuarantee second of increasing trend energy
It enough detects, therefore to be slightly smaller than the Δ I when determining the first commutation failure featureincN, then:
3) judge above-mentioned output LincD(n) with the presence or absence of the incremental spacing time T of increasing trend twiceD(n) whether it is greater than and changes
Flow the incremental spacing time T of valve current on valve side increasing trend twice under normal operationC, if so, with high level LBD(t)
It maintains to signal LincD(n) the failing edge P of high levelincD(n) moment, that is, there is no be incremented by become twice within a preset time
Gesture, at this point, output LB(n)；
Wherein,There is LincD, also, L (n)=0incD(nB- 1)=1, LincD(nB)=0.
It 4) is to guarantee that current on valve side is after being incremented to zero by negative value in time t2Inside it is incremented by again, by LincD(n) it is changed with first
The mutually L in failure featureIP(n) the delay time t again after "AND" logic2, obtain LDP(n)；
LDP(n)=(LIP(n)·LincD(n))·delay(t2)；
5) by LB(n) it negates, then and LincD(n)、LDP(n) through "AND" logic, second of increment signal L is obtainedD(n)；
LD(n)=(1-LB(n))·LincD(n)·LDP(n)；
6) by LD(n) it maintains until second of increasing trend terminates, obtains LDH(n), then through time t3Delay, then with the
Successively decreasing in one commutation failure feature judges signal LdecNThrough "AND" logic, when obtaining valve side j phase current commutation failure, second is changed
The mutually testing result L of failure featureCFj-2(n)；
LCFj_2(n)=LDH(n)·delay(t3)·LdecN(n)。
As shown in figure 9, being the detection logical schematic for the single-phase current on valve side commutation failure that this example provides.In this implementation
It is with L respectively in exampleCFj-1(n) and LCFj-2(n) testing result obtained by current on valve side-ij is indicated, then j phase current on valve side
It is L that the result of commutation failure, which whether occurs,CFj(n), therefore by LCFj-1(n)、LCFj-2(n)、LCFj-1(n) and LCFj-2(n) it passes through
Testing result L of the "or" logic as single-phase current on valve sideCFj(n)。
In practical application, traditional direct current transportation uses 12 pulse conversion devices substantially in engineering, to distinguish two difference
Become 6 pulse conversion devices current on valve side being coupled with Y/D connection and the Y/Y connection change of current, each phase current is distinguished with d and y, then j
=da, db, dc, ya, yc, yd.Finally two kinds of situation features of each phase current in above-mentioned valve side are detected through "or" logic as final
Commutation Failure testing result LCF(n), logic is as shown in Figure 10.
In addition, in the present embodiment, CIGRE HVDC standard test models are also based on, in electromagnetic transient simulation software
PSCAD/EMTDC builds the above-mentioned commutation failure detection module based on current on valve side feature, is arranged not in inverter side ac bus
Same failure, to verify the feasibility and reliability of the proposed commutation failure detection method of the application.The application is verified to be proposed
Accuracy based on the commutation failure detection method of current on valve side under various failures is to choose typical three-phase in this application
Failure is as instance analysis.
It as shown in figure 11, is the schematic diagram of direct current transportation fault setting provided in this embodiment.In inverter side ac bus
Three-phase ground failure is set, it is assumed that failure initial time is 3.0s, continues 100ms, and short circuit grounding inductance is taken as 0.8H, emulation knot
Fruit is referring to Figure 12, Figure 13 and Figure 14.It as shown in figure 12, is inverter side AC and DC voltage and valve current wave when commutation failure occurs
The schematic diagram of shape；It as shown in figure 13, is the schematic diagram of inverter side converter transformer valve-side current waveform when commutation failure occurs；Such as
It is the schematic diagram of the commutation failure testing result based on converter transformer valve-side current characteristic shown in Figure 14.
As shown in Figure 12, after three-phase fault occurs, valve VD3 is switched to commutation failure occurs at first when valve VD5 commutation
Phase start time is tm1=3.0052s, about 0.0009s (are equivalent to) valve VD6 is connected afterwards, that is, there are for current on valve side
One commutation failure feature.6 pulse conversion devices DC sides being coupled with the change of current of Y/D connection change will be made to be formed after valve VD6 conducting
Short circuit, inverter back-emf about drop by half.Thereafter, become the valve VY5 in 6 pulse conversion devices being coupled with the change of current of Y/Y connection
To commutation failure occurs when valve VY1 commutation, switching phase start time is tm2=3.0108s, and valve VY2 is started simultaneously at substantially and is led
It is logical, that is, there are the second commutation failure features for current on valve side.After valve VY2 conducting, entire 12 pulse conversion devices DC side shape will be made
At short circuit, inverter back-emf is become zero.
As the above analysis, the converter transformer valve-side b phase current idb for the Y/D connection connecting with valve VD3 will occur
One commutation failure feature, and the converter transformer valve-side c phase current i for the Y/Y connection being connect with valve VY5ycThe second commutation to occur
Failure feature, as shown in figure 13, current on valve side waveform demonstrates the correctness of the analysis.As shown in figure 14, to be become based on the change of current
The schematic diagram of the commutation failure testing result of depressor current on valve side feature.As shown in Figure 14, commutation failure provided herein
Detection method can accurately detect commutation failure.Moreover, can be also accurately judged to by testing result is that valve has occurred in which
Commutation failure.For example, if detection signal LCFj-1(or LCFj-2) output high level, illustrate to become 6 be coupled with the change of current of Y/D connection
The valve VD5 being connected in pulse conversion devices with c is to occurring commutation failure when valve VD1 commutation；If detecting signal LCFj-1(or
LCFj-2) output high level, illustrate the valve VD2 being connected in 6 pulse conversion devices being coupled with the change of current of Y/D connection change with c to valve
Commutation failure occurs when VD4 commutation, other situations are similar.
As shown in Figure 14, using method provided by the present embodiment, respectively in tD1=3.00564s and tD2=3.0124s
Detect commutation failure, i.e., it is only t that deviation at the time of switching phase and actually takes place respectivelyD1-tm1=0.44ms and tD2-tm2
=1.60ms, the experimental results showed that, the method that the application is proposed can quickly, accurately detect whether converter valve occurs commutation
Failure.
Correspondingly, the embodiment of the invention also discloses a kind of, the high voltage direct current commutation failure based on converter transformer valve side electric current is examined
Device is surveyed, as shown in figure 15, comprising:
Waveform obtains module 21, for obtaining the waveform of converter transformer valve-side electric current；
Waveform comparison module 22, for the converter transformer valve-side electric current by waveform and converter valve under normal operation
Waveform be compared, to determine whether converter valve occurs commutation failure.
Correspondingly, the embodiment of the invention also discloses a kind of computer readable storage medium, computer readable storage medium
On be stored with computer program, when computer program is executed by processor realize as previously disclosed be based on converter transformer valve side electric current
High voltage direct current commutation failure detection method the step of.
Correspondingly, the embodiment of the invention also discloses a kind of, the high voltage direct current commutation failure based on converter transformer valve side electric current is examined
Measurement equipment, as shown in figure 16, comprising:
Memory, for storing computer program；
Processor is realized when for executing computer program as previously disclosed based on the high straightening of converter transformer valve side electric current
The step of flowing commutation failure detection method.
Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with it is other
The difference of embodiment, same or similar part may refer to each other between each embodiment.For being filled disclosed in embodiment
For setting, since it is corresponded to the methods disclosed in the examples, so being described relatively simple, related place is referring to method part
Explanation.
Finally, it is to be noted that, herein, relational terms such as first and second and the like be used merely to by
One entity or operation are distinguished with another entity or operation, without necessarily requiring or implying these entities or operation
Between there are any actual relationship or orders.Moreover, the terms "include", "comprise" or its any other variant meaning
Covering non-exclusive inclusion, so that the process, method, article or equipment for including a series of elements not only includes that
A little elements, but also including other elements that are not explicitly listed, or further include for this process, method, article or
The intrinsic element of equipment.In the absence of more restrictions, the element limited by sentence "including a ...", is not arranged
Except there is also other identical elements in the process, method, article or apparatus that includes the element.
Above to a kind of high voltage direct current commutation failure detection method based on converter transformer valve side electric current provided by the present invention,
Device, medium and equipment are described in detail, specific case used herein to the principle of the present invention and embodiment into
Elaboration is gone, the above description of the embodiment is only used to help understand the method for the present invention and its core ideas；Meanwhile for this
The those skilled in the art in field, according to the thought of the present invention, there will be changes in the specific implementation manner and application range,
In conclusion the contents of this specification are not to be construed as limiting the invention.
Claims (10)
1. a kind of high voltage direct current commutation failure detection method based on converter transformer valve side electric current characterized by comprising
Obtain the waveform of converter transformer valve-side electric current；
The waveform of converter transformer valve-side electric current by the waveform with converter valve under normal operation is compared, to sentence
Whether the fixed converter valve occurs commutation failure.
2. the method according to claim 1, wherein the mistake of the waveform for obtaining converter transformer valve-side electric current
Journey, comprising:
Obtain the target waveform when converter transformer valve-side electric current is negative value；
Correspondingly, the waveform of the converter transformer valve-side electric current by the waveform and converter valve under normal operation into
Row compares, to determine whether the converter valve occurs the process of commutation failure, comprising:
Judge the target waveform with the presence or absence of an increasing trend；
If so, judging whether an increasing trend is greater than the first preset threshold；
If so, judging the target waveform with the presence or absence of maximum；
If so, after judging that the target waveform reaches the maximum, whether the decline trend of the target waveform is greater than the
Two preset thresholds；
If so, determining the converter transformer valve-side electric current, there are the first commutation failure features；
Judge the target waveform with the presence or absence of increasing trend twice；
If so, whether the judgement increasing trend twice is greater than third predetermined threshold value；
If so, whether the incremental spacing time of the judgement increasing trend twice is less than the converter valve in normal operation
Under the converter transformer valve-side electric current waveform increasing trend twice the incremental spacing time；
Successively decrease if so, judging whether the target waveform exists after the increasing trend twice in preset time threshold
Gesture；
If so, determining the converter transformer valve-side electric current, there are the second commutation failure features；
Judge the target waveform with the presence or absence of the first commutation failure feature and/or the second commutation failure feature；
If so, determining that the commutation failure occurs for the converter valve.
3. according to the method described in claim 2, it is characterized by further comprising:
The detection any one phase current of converter transformer valve-side is changed with the presence or absence of the first commutation failure feature and/or described second
Mutually failure feature；
If so, determining that the commutation failure occurs for inverter.
4. according to the method described in claim 2, it is characterized by further comprising:
When the converter transformer valve-side electric current is negative value, the first signal is exported；
When an increasing trend is greater than first preset threshold, second signal is exported；
It detects first signal and whether the second signal exists；
If so, output third signal；
When the target waveform is there are when the maximum, fourth signal is exported；
After the target waveform reaches the maximum, the decline trend of the target waveform is greater than second preset threshold
When, export the 5th signal；
Detect whether the third signal, fourth signal and the 5th signal exist；
If so, determining the converter transformer valve-side electric current, there are the first commutation failure features.
5. according to the method described in claim 4, it is characterized in that, first signal, the second signal, the third are believed
Number, the fourth signal and the 5th signal be level signal.
6. according to the method described in claim 5, it is characterized by further comprising:
First signal and/or the second signal and/or the third signal and/or described are detected using logic gates
Fourth signal and/or the 5th signal whether there is.
7. according to the method described in claim 4, it is characterized by further comprising:
When increasing trend is greater than the third predetermined threshold value twice described in the target waveform, the 6th signal is exported；
In the presence of first signal and the 6th signal are equal, the 7th signal is exported；
Become when the incremental spacing time of the increasing trend twice is less than converter valve change of current under normal operation
When the incremental spacing time of the increasing trend twice of the waveform of depressor current on valve side, the 8th signal is exported；
When the 6th signal, the 7th signal and the 8th signal it is equal in the presence of, export the 9th signal；
Start to successively decrease described in presentation in the preset time threshold after target waveform is in the increasing trend twice
Gesture exports the tenth signal；
In the presence of the 9th signal and the tenth signal are equal, then determine described in the converter transformer valve-side electric current presence
Second commutation failure feature.
8. a kind of high voltage direct current commutation failure detection device based on converter transformer valve side electric current characterized by comprising
Waveform obtains module, for obtaining the waveform of converter transformer valve-side electric current；
Waveform comparison module, for the converter transformer valve-side electric current by the waveform and converter valve under normal operation
Waveform is compared, to determine whether the converter valve occurs commutation failure.
9. a kind of computer readable storage medium, which is characterized in that be stored with computer on the computer readable storage medium
Program, the computer program are realized as described in any one of claim 1 to 7 based on converter transformer valve side when being executed by processor
The step of high voltage direct current commutation failure detection method of electric current.
10. a kind of high voltage direct current commutation failure detection device based on converter transformer valve side electric current characterized by comprising
Memory, for storing computer program；
Processor is realized as described in any one of claim 1 to 7 based on converter transformer valve when for executing the computer program
The step of high voltage direct current commutation failure detection method of side electric current.
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| CN111239471A (en) * | 2020-01-19 | 2020-06-05 | 华南理工大学 | Commutation failure protection method and device, computer equipment and storage medium |
| CN111276993A (en) * | 2020-01-22 | 2020-06-12 | 华南理工大学 | Controller parameter setting method, medium and equipment applied to high-voltage direct-current transmission |
| CN111628482A (en) * | 2020-04-27 | 2020-09-04 | 清华大学 | Current converter overcurrent protection device and method |
| 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 |
| CN113866550A (en) * | 2021-07-19 | 2021-12-31 | 许继集团有限公司 | Method and device for detecting commutation abnormity of high-voltage direct-current transmission |
| CN113933619A (en) * | 2021-09-10 | 2022-01-14 | 南方电网科学研究院有限责任公司 | Commutation failure detection method and device |
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| CN111239471A (en) * | 2020-01-19 | 2020-06-05 | 华南理工大学 | Commutation failure protection method and device, computer equipment and storage medium |
| CN111276993A (en) * | 2020-01-22 | 2020-06-12 | 华南理工大学 | Controller parameter setting method, medium and equipment applied to high-voltage direct-current transmission |
| CN111628482A (en) * | 2020-04-27 | 2020-09-04 | 清华大学 | Current converter overcurrent protection device and method |
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