CN104749475B - A kind of locomotive island detection method and system - Google Patents
A kind of locomotive island detection method and system Download PDFInfo
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Abstract
A kind of locomotive island detection method that the application is provided, this method includes：In the case where net surveys the normal operation of current transformer, collection main transformer original edge voltage and full middle dc voltage；Obtain the on off state that the net surveys the current each phase of current transformer；According to the full middle dc voltage and the on off state of current each phase, according to preset formula, virtual net pressure is calculated；Virtual net pressure is compared with the main transformer original edge voltage, when the virtual net presses the difference with the main transformer original edge voltage to meet preparatory condition, then judges occur isolated island failure.The application uses the island detection method of virtual net pressure, can effectively carry out the detection of locomotive isolated island.
Description
Technical field
The application is related to isolated island detection field, more particularly to a kind of locomotive island detection method and system.
Background technology
With the development of technology, the requirement more and more higher that people detect to locomotive isolated island.
Existing locomotive island detection method general algorithm is complicated, and detection time is long, it is difficult to Project Realization, and its detection
The degree of accuracy is difficult to engineering verification.
Therefore, the detection for how effectively carrying out locomotive isolated island is that those skilled in the art need the technology solved to ask at present
Topic.
The content of the invention
Technical problems to be solved in this application are to provide a kind of locomotive island detection method and system, can effectively enter
The detection of row locomotive isolated island.
Its concrete scheme is as follows：
A kind of locomotive island detection method, this method includes：
In the case where net surveys the normal operation of current transformer, collection main transformer original edge voltage and full middle dc voltage；
Obtain the on off state that the net surveys the current each phase of current transformer；
According to the full middle dc voltage and the on off state of current each phase, according to preset formula, calculate virtual
Net pressure；
Virtual net pressure is compared with the main transformer original edge voltage, when virtual net pressure and the main transformer
When the difference of depressor original edge voltage meets preparatory condition, then judge occur isolated island failure.
Above-mentioned method, it is preferred that it is described according to the full middle dc voltage and current each phase on off state,
According to preset formula, virtual net pressure is calculated, including：
According to the full middle dc voltage and the on off state of current each phase, calculate the net and survey current transformer exchange
The voltage of input；
The no-load voltage ratio of voltage, leakage inductance and the transformer of current transformer ac input end is surveyed according to the net, according to preset formula, meter
Calculate virtual net pressure.
Above-mentioned method, it is preferred that described to be compared virtual net pressure with the main transformer original edge voltage, when
When the virtual net pressure and the difference of the main transformer original edge voltage meet preparatory condition, then judge that isolated island event occurs for locomotive
Barrier, including：
Set the threshold value that isolated island judges；
When the virtual net presses the difference with the main transformer original edge voltage to be more than or equal to the door that the isolated island judges
During threshold value, then judge that isolated island failure occurs for locomotive.
A kind of locomotive alone island detection system, the system includes：
Collecting unit, in the case of surveying the normal operation of current transformer in net, in gathering main transformer original edge voltage and being complete
Between DC voltage；
Acquiring unit, the on off state of the current each phase of current transformer is surveyed for obtaining the net；
Computing unit, for the on off state according to the full middle dc voltage and current each phase, according to default
Formula, calculates virtual net pressure；
Comparing unit, for virtual net pressure to be compared with the main transformer original edge voltage, when described virtual
When net pressure and the difference of the main transformer original edge voltage meet preparatory condition, then judge occur isolated island failure.
Above-mentioned system, it is preferred that the computing unit includes：
First computation subunit, for the on off state according to the full middle dc voltage and current each phase, meter
Calculate the voltage that the net surveys current transformer ac input end；
Second computation subunit, for the voltage according to the net survey current transformer ac input end, leakage inductance and transformer
No-load voltage ratio, according to preset formula, calculates virtual net pressure.
Above-mentioned system, it is preferred that the comparing unit includes：
Setup unit, the threshold value for setting isolated island judgement；
Judging unit, for pressing the difference with the main transformer original edge voltage more than or equal to described when the virtual net
During the threshold value that isolated island judges, then judge that isolated island failure occurs for locomotive.
In a kind of locomotive island detection method that the application is provided, first, in the case where net surveys the normal operation of current transformer,
Gather main transformer original edge voltage and full middle dc voltage；Obtain the on off state that the net surveys the current each phase of current transformer；So
Afterwards, according to the full middle dc voltage and the on off state of current each phase, according to preset formula, virtual net pressure is calculated；
Finally, virtual net pressure is compared with the main transformer original edge voltage, when virtual net pressure and the main transformer pressure
When the difference of device original edge voltage meets preparatory condition, then judge occur isolated island failure.The application is examined using the isolated island of virtual net pressure
Survey method, can effectively carry out the detection of locomotive isolated island.
Brief description of the drawings
In order to illustrate more clearly of the technical scheme in the embodiment of the present application, make required in being described below to embodiment
Accompanying drawing is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the present application, for
For those of ordinary skill in the art, without having to pay creative labor, it can also be obtained according to these accompanying drawings
His accompanying drawing.
Fig. 1 is a kind of flow chart of locomotive island detection method embodiment of the application；
Fig. 2 is the major loop topology diagram of alternating current electric locomotive in the application；
Fig. 3 is a kind of structural representation of locomotive alone island detection system embodiment of the application.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present application, the technical scheme in the embodiment of the present application is carried out clear, complete
Site preparation is described, it is clear that described embodiment is only some embodiments of the present application, rather than whole embodiments.It is based on
Embodiment in the application, it is every other that those of ordinary skill in the art are obtained under the premise of creative work is not made
Embodiment, belongs to the scope of the application protection.
With reference to Fig. 1, a kind of flow chart of locomotive island detection method embodiment of the application is shown, following step can be included
Suddenly：
Step S101：In the case where net surveys the normal operation of current transformer, main transformer original edge voltage is gathered and complete middle straight
Flow voltage.
Step S102：Obtain the on off state that the net surveys the current each phase of current transformer.
Step S103：According to the full middle dc voltage and the on off state of current each phase, according to preset formula,
Calculate virtual net pressure.
In the application, it is described according to the full middle dc voltage and current each phase on off state, according to default
Formula, calculates virtual net pressure, including：
According to the full middle dc voltage and the on off state of current each phase, calculate the net and survey current transformer exchange
The voltage of input.
The no-load voltage ratio of voltage, leakage inductance and the transformer of current transformer ac input end is surveyed according to the net, according to preset formula, meter
Calculate virtual net pressure.
Step S104：Virtual net pressure is compared with the main transformer original edge voltage, when the virtual net pressure
When meeting preparatory condition with the difference of the main transformer original edge voltage, then judge occur isolated island failure.
It is described to be compared virtual net pressure with the main transformer original edge voltage in the application, when described virtual
When net pressure and the difference of the main transformer original edge voltage meet preparatory condition, then judge that isolated island failure occurs for locomotive, including：
Set the threshold value that isolated island judges.
When the virtual net presses the difference with the main transformer original edge voltage to be more than or equal to the door that the isolated island judges
During threshold value, then judge that isolated island failure occurs for locomotive.
Present invention take advantage of that the characteristic of net side current transformer itself, builds one " virtual net pressure ", this " virtual net pressure " is
Estimated by net side current transformer according to itself on off state and tractive transformer leakage reactance, in locomotive accidental conditions
Under, the Traction networks pressure of " virtual net pressure " and actual acquisition is substantially consistent, but at the time of isolated island occurs, due to not big electricity
Net clamps down on effect, and voltage magnitude, electric voltage frequency, the input current of net side current transformer of Traction networks can all occur certain abnormal
Become, thus " the virtual net pressure " derived just and actual acquisition Traction networks pressure life than larger difference, utilize this difference
It is different, it is possible to whether to identify locomotive in island state.
Fig. 2 shows the major loop topology diagram of alternating current electric locomotive in the application, from figure 2 it can be seen that UNFor traction
Primary voltage of transformer；UinFor a certain heavy four quadrant convertor AC input voltage；UdFor on current transformer intermediate dc loop
DC voltage, the input current of net side current transformer is i1。
The flow of isolated island detection in the application is as follows：
When net side current transformer is normally run, tractive transformer original edge voltage U is gatheredN, on current transformer intermediate dc loop
DC voltage Ud, and during control net side current transformer, the on off state of net side current transformer is learned, in the system of multiplex
In, if a certain heavy net side current transformer A phases on off state is Sa, B phases on off state is Sb, then this heavy net side unsteady flow can be obtained
The voltage of device ac input end：
Uin=(Sa-Sb)*Ud
Assuming that the equivalent leakage inductance size to secondary side of tractive transformer is Lin, the no-load voltage ratio of transformer is KN, then " virtual net pressure "
Calculation formula be：
Obtain virtual net pressure UestiAfterwards, it is assumed that the threshold that isolated island judges is gate, by judging abs (Uesti-UN) judge
With the presence or absence of isolated island operating mode, as abs (Uesti-UNDuring) >=gate, isolated island failure, abs (U occur for systemesti-UN) ＜ gate when,
Isolated island failure does not occur for system.
In a kind of locomotive island detection method that the application is provided, first, in the case where net surveys the normal operation of current transformer,
Gather main transformer original edge voltage and full middle dc voltage；Obtain the on off state that the net surveys the current each phase of current transformer；So
Afterwards, according to the full middle dc voltage and the on off state of current each phase, according to preset formula, virtual net pressure is calculated；
Finally, virtual net pressure is compared with the main transformer original edge voltage, when virtual net pressure and the main transformer pressure
When the difference of device original edge voltage meets preparatory condition, then judge occur isolated island failure.The application is examined using the isolated island of virtual net pressure
Survey method, can effectively carry out the detection of locomotive isolated island, and be suitably applied locomotive field；It is adapted to power electronic system to become
Flow the system of device；It is adapted to realize possess actual engineering application value with software algorithm；Operation, Traction networks to locomotive
The quality of power supply does not influence.
Corresponding with a kind of locomotive island detection method embodiment of above-mentioned the application, referring to Fig. 3, present invention also provides one
Locomotive alone island detection system is planted, in this embodiment, the system includes：
Collecting unit 301, in the case of surveying the normal operation of current transformer in net, gathers main transformer original edge voltage and complete
Middle dc voltage.
Acquiring unit 302, the on off state of the current each phase of current transformer is surveyed for obtaining the net.
Computing unit 303, for the on off state according to the full middle dc voltage and current each phase, according to pre-
If formula, virtual net pressure is calculated.
Comparing unit 304, for virtual net pressure to be compared with the main transformer original edge voltage, when the void
When plan net pressure and the difference of the main transformer original edge voltage meet preparatory condition, then generation isolated island failure is judged.
In the application, the computing unit includes：
First computation subunit, for the on off state according to the full middle dc voltage and current each phase, meter
Calculate the voltage that the net surveys current transformer ac input end；
Second computation subunit, for the voltage according to the net survey current transformer ac input end, leakage inductance and transformer
No-load voltage ratio, according to preset formula, calculates virtual net pressure.
The comparing unit includes：
Setup unit, the threshold value for setting isolated island judgement；
Judging unit, for pressing the difference with the main transformer original edge voltage more than or equal to described when the virtual net
During the threshold value that isolated island judges, then judge that isolated island failure occurs for locomotive.
It should be noted that each embodiment in this specification is described by the way of progressive, each embodiment weight
Point explanation be all between difference with other embodiment, each embodiment identical similar part mutually referring to.
For device class embodiment, because it is substantially similar to embodiment of the method, so description is fairly simple, related part is joined
See the part explanation of embodiment of the method.
Finally, in addition it is also necessary to explanation, herein, such as first and second or the like relational terms be used merely to by
One entity or operation make a distinction with another entity or operation, and not necessarily require or imply these entities or operation
Between there is any this actual relation or order.Moreover, term " comprising ", "comprising" or its any other variant meaning
Covering including for nonexcludability, so that process, method, article or equipment including a series of key elements not only include that
A little key elements, but also other key elements including being not expressly set out, or also include be this process, method, article or
The intrinsic key element of equipment.In the absence of more restrictions, the key element limited by sentence "including a ...", is not arranged
Except also there is other identical element in the process including the key element, method, article or equipment.
For convenience of description, it is divided into various units during description apparatus above with function to describe respectively.Certainly, this is being implemented
The function of each unit can be realized in same or multiple softwares and/or hardware during application.
As seen through the above description of the embodiments, those skilled in the art can be understood that the application can
Realized by the mode of software plus required general hardware platform.Understood based on such, the technical scheme essence of the application
On the part that is contributed in other words to prior art can be embodied in the form of software product, the computer software product
It can be stored in storage medium, such as ROM/RAM, magnetic disc, CD, including some instructions are to cause a computer equipment
(can be personal computer, server, or network equipment etc.) performs some of each embodiment of the application or embodiment
Method described in part.
A kind of locomotive island detection method provided herein and system are described in detail above, herein should
The principle and embodiment of the application are set forth with specific case, the explanation of above example is only intended to help and managed
Solve the present processes and its core concept；Simultaneously for those of ordinary skill in the art, according to the thought of the application,
It will change in embodiment and application, in summary, this specification content should not be construed as to this Shen
Limitation please.
Claims (4)
1. a kind of locomotive island detection method, it is characterised in that this method includes：
In the case where net side current transformer is normally run, main transformer original edge voltage U is gatheredNWith full middle dc voltage Ud；
Obtain the on off state of the current each phase of the net side current transformer；
According to the full middle dc voltage and the on off state of current each phase, according to preset formula, virtual net pressure is calculated；
Wherein, the preset formula is：
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Uin=(Sa-Sb)*Ud, SaFor net side current transformer A phase on off states, SbFor B phase on off states, LinFor tractive transformer etc.
Imitate the leakage inductance size of secondary side, KNFor the no-load voltage ratio of transformer；UinFor a certain heavy four quadrant convertor AC input voltage；UdFor
DC voltage on current transformer intermediate dc loop, i1For the input current of net side current transformer；
Set the threshold value that isolated island judges；
When the virtual net presses the difference with the main transformer original edge voltage to be more than or equal to the threshold value that the isolated island judges
When, then judge that isolated island failure occurs for locomotive.
2. according to the method described in claim 1, it is characterised in that described according to the full middle dc voltage and described current
The on off state of each phase, according to preset formula, calculates virtual net pressure, including：
According to the full middle dc voltage and the on off state of current each phase, the net side current transformer exchange input is calculated
The voltage at end；
According to the no-load voltage ratio of the voltage of the net side current transformer ac input end, leakage inductance and transformer, according to preset formula, calculate empty
Intend net pressure.
3. a kind of locomotive alone island detection system, it is characterised in that the system includes：
Collecting unit, in the case of normally being run in net side current transformer, gathers main transformer original edge voltage UNIt is straight with full centre
Flow voltage Ud；
Acquiring unit, the on off state for obtaining the current each phase of the net side current transformer；
Computing unit, for the on off state according to the full middle dc voltage and current each phase, according to preset formula,
Calculate virtual net pressure；Wherein, the preset formula is：
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Uin=(Sa-Sb)*Ud, SaFor net side current transformer A phase on off states, SbFor B phase on off states, LinFor tractive transformer etc.
Imitate the leakage inductance size of secondary side, KNFor the no-load voltage ratio of transformer；UinFor a certain heavy four quadrant convertor AC input voltage；UdFor
DC voltage on current transformer intermediate dc loop, i1For the input current of net side current transformer；
Comparing unit, the threshold value for setting isolated island judgement；When the virtual net is pressed and the main transformer original edge voltage
When difference is more than or equal to the threshold value that the isolated island judges, then judge that isolated island failure occurs for locomotive.
4. system according to claim 3, it is characterised in that the computing unit includes：
First computation subunit, for the on off state according to the full middle dc voltage and current each phase, calculates institute
State the voltage of net side current transformer ac input end；
Second computation subunit, for the no-load voltage ratio of the voltage according to the net side current transformer ac input end, leakage inductance and transformer,
According to preset formula, virtual net pressure is calculated.
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