CN113937705B - Alternating-current ice melting device for railway traction network and control method thereof - Google Patents
Alternating-current ice melting device for railway traction network and control method thereof Download PDFInfo
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- CN113937705B CN113937705B CN202111202817.3A CN202111202817A CN113937705B CN 113937705 B CN113937705 B CN 113937705B CN 202111202817 A CN202111202817 A CN 202111202817A CN 113937705 B CN113937705 B CN 113937705B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G7/00—Overhead installations of electric lines or cables
- H02G7/16—Devices for removing snow or ice from lines or cables
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M5/4585—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only having a rectifier with controlled elements
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/40—Heating elements having the shape of rods or tubes
- H05B3/54—Heating elements having the shape of rods or tubes flexible
- H05B3/56—Heating cables
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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
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/30—Reactive power compensation
Abstract
The invention discloses an alternating-current ice melting device for a railway traction network and a control method thereof. The icing of the railway traction network is an extremely serious natural disaster which causes the railway to be shut down. The invention comprises a shunt transformer, a series transformer, two groups of single-phase fully-controlled bridges, a series-parallel energy storage smoothing capacitor group, two groups of LCR filters and a high-capacity high-voltage reactor, and is controlled by adopting a multi-component comprehensive voltage stabilization method and a capacity shunt injection method. The existence of the series transformer and the shunt transformer greatly reduces the voltage grade of the full control bridge, and reactive current is injected into a traction network system together through a shunt loop and a high-voltage large-capacity reactor, so that the current of the ice melting device can be larger, and the operation is more flexible due to capacity shunt; the full-control bridge and the traditional high-voltage large-capacity reactor are used in a mixed mode, and the reliability of the device is improved.
Description
Technical Field
The invention belongs to the technical field of railway traction power supply and distribution, and particularly relates to a railway traction network alternating-current ice melting device and a control method thereof.
Background
The railway is one of the major arteries for economic development, the safe, stable, rapid and efficient operation of the railway is not realized, and the development of social economy and the demands of civilian life are greatly influenced. Particularly, in recent years, with the rapid development of information technology, once a significant event concerning the growth of civilian and social life occurs, it is rapidly fermented and amplified in a very short time. Therefore, it has become increasingly important to ensure safe and stable operation of railways and to reduce the occurrence of outages. The icing of the railway traction network is a serious natural disaster which causes the railway shutdown, and particularly in the event of ice disaster in Hunan in 2008 and large-scale icing in northeast in 2020, the ice melting requirement of the railway traction network is more urgent and has great practical significance. In fact, a small range of extreme weather events occur in various regions every year, but no larger range of influence is formed. Therefore, the device or the scheme which can be flexibly connected to the contact network and can quickly and reliably melt the ice coated on the contact network is urgently needed.
Disclosure of Invention
In order to make up for the defects of the prior art, the invention provides the alternating-current deicing device for the railway traction network and the control method thereof, which can quickly and reliably melt the ice coated on the contact network.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a railway traction network alternating-current ice melting device comprises a shunt transformer T1, a series transformer T2, two groups of single-phase fully-controlled bridges, a series-parallel energy storage smoothing capacitor group C, two groups of LCR filters and a high-capacity high-voltage reactor L3, wherein one end of the high-voltage side of the shunt transformer T1 and one end of the high-voltage side of the series transformer T2 are connected in parallel to the position of a P point at the tail end of a railway traction network circuit;
the other end of the high-voltage side of the series transformer T2 is connected with one end of a high-capacity high-voltage reactor L3, and the other end of the high-capacity high-voltage reactor L3 and the other end of the high-voltage side of the shunt transformer T1 are connected to the position of an N point on a railway traction network return line in parallel;
the direct current sides of the two groups of single-phase fully-controlled bridges are connected with the series-parallel connection type energy storage smoothing capacitor bank C in parallel, and the alternating current sides of the two groups of single-phase fully-controlled bridges are respectively connected with the low-voltage side of the shunt transformer T1 and the low-voltage side of the series transformer T2 after passing through the LCR filter.
A control method of a railway traction network alternating-current ice melting device adopts a multi-component comprehensive voltage stabilization method and a capacity split injection method for control;
specifically, in the multi-component comprehensive voltage stabilization method, a series voltage stabilization loop is formed by using a single-phase fully controlled bridge H2, an LCR filter 2 and a series transformer T2 for the direct-current voltage stabilization control of two ends of a series-parallel type energy storage smoothing capacitor bank C; the single-phase full-control bridge H1, the LCR filter 1 and the shunt transformer T1 form a shunt voltage stabilizing loop, and the series voltage stabilizing loop and the shunt voltage stabilizing loop comprehensively perform direct-current voltage stabilization control;
specifically, in the capacity shunt injection method, a large-capacity high-voltage reactor L3 is connected to the two ends of P, N through a series transformer T2, and inductive reactive current flows into a traction network connection system; the single-phase full-control bridge H1 and the LCR filter 1 are connected to the two ends of P, N through a shunt transformer T1, and inductive reactive current is injected into a traction network system; and distributing the two parts of inductive reactive current according to the required ice melting current capacity.
The invention has the beneficial effects that:
1) The invention realizes the combined stabilization of the direct current voltage by the series circuit and the parallel circuit, so that the system operation is more stable;
2) According to the invention, the reactive current is injected into the traction network system together through the parallel loop and the high-voltage large-capacity reactor, so that the current of the ice melting device can be larger, and the capacity shunt enables the operation to be more flexible;
3) The existence of the series transformer and the parallel transformer greatly reduces the voltage grade of the full-controlled bridge and reduces the device cost caused by voltage;
4) According to the invention, through the mixed use of the power electronic full-control bridge and the traditional high-voltage large-capacity reactor, even if the full-control bridge of the parallel part is damaged, the current required by partial ice melting can be provided by the large-capacity reactor in an emergency, so that the reliability of the device is improved.
Drawings
FIG. 1 is a schematic illustration of the present invention in connection with a railroad traction network;
fig. 2 is a topological structure diagram of the present invention.
Detailed Description
The present invention will be described in detail with reference to specific embodiments.
As shown in fig. 1, a schematic diagram of the connection between the ice melting device and a railway traction network and fig. 2, a topological structure diagram of the ice melting device is shown, wherein the ice melting device comprises a parallel transformer T1, a series transformer T2, two groups of single-phase fully-controlled bridges, a series-parallel energy storage smoothing capacitor group C, two groups of LCR filters and a high-capacity high-voltage reactor L3;
one end of the high-voltage side of the parallel transformer T1 and one end of the high-voltage side of the series transformer T2 are connected in parallel to the position of a P point at the tail end of the railway traction network circuit; the other end of the high-voltage side of the series transformer T2 is connected with one end of a high-capacity high-voltage reactor L3, and the other end of the high-capacity high-voltage reactor L3 and the other end of the high-voltage side of the shunt transformer T1 are connected in parallel with the position of an N point on a railway traction network return line; the direct current sides of the two groups of single-phase fully-controlled bridges are connected with the series-parallel connection type energy storage smoothing capacitor bank C in parallel, and the alternating current sides of the two groups of single-phase fully-controlled bridges are respectively connected with the low-voltage side of the shunt transformer T1 and the low-voltage side of the series transformer T2 after passing through the LCR filter; the parallel connection points P and N are access points of the device and the railway traction network, wherein the parallel connection point P is connected to 27.5kV of the railway traction network, and the parallel connection point N is connected to a return end or a return line of the railway traction network.
The invention adopts a multi-component comprehensive pressure stabilization method and a capacity split injection method for control;
in the multi-component comprehensive voltage stabilization method, a series voltage stabilization loop is formed by using a single-phase fully controlled bridge H2, an LCR filter 2 and a series transformer T2 to perform direct-current voltage stabilization control on two ends of a series-parallel energy storage flat wave capacitor bank C; the single-phase full-control bridge H1, the LCR filter 1 and the shunt transformer T1 form a shunt voltage stabilizing loop, and the series voltage stabilizing loop and the shunt voltage stabilizing loop comprehensively carry out direct-current voltage stabilization control;
in the capacity shunt injection method, a large-capacity high-voltage reactor L3 is connected to the two ends of P, N through a series transformer T2, and inductive reactive current flows into a traction network connection system; the single-phase full-control bridge H1 and the LCR filter 1 are connected to the two ends of P, N through a shunt transformer T1, and inductive reactive current is injected into a traction network system; and distributing the two parts of inductive reactive current according to the required ice melting current capacity.
The ice melting device leads the ice coating melting principle of the traction network circuit to be as follows: reactive current is generated through the ice melting device on the basis of the action of traction voltage of a railway traction network, the reactive current acts on line impedance to generate Joule heat, and the Joule heat melts ice coated on the line.
In the description of the present invention, unless otherwise expressly specified or limited, the terms "disposed," "mounted," "connected," "fixed," "single-phase all-controlled bridge," or "single-phase all-controlled bridge" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; the two components can be directly connected or indirectly connected through an intermediate medium, and can be communicated with each other inside the two components or in an interaction relationship of the two components; the single-phase fully-controlled bridge can be a single-phase single H bridge or a single-phase cascade H bridge. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The invention is not limited to the examples, and any equivalent changes to the technical solution of the invention by a person skilled in the art after reading the description of the invention are covered by the claims of the invention.
Claims (2)
1. The utility model provides a railway traction net exchanges ice-melt device, includes shunt transformer T1, series transformer T2, two sets of single-phase full control bridges, series-parallel connection type energy storage smoothing capacitor group C, two sets of LCR wave filters and large capacity high voltage reactor L3, its characterized in that: one end of the high-voltage side of the parallel transformer T1 and one end of the high-voltage side of the series transformer T2 are connected in parallel to the position of a P point at the tail end of the railway traction network circuit;
the other end of the high-voltage side of the series transformer T2 is connected with one end of a high-capacity high-voltage reactor L3, and the other end of the high-capacity high-voltage reactor L3 and the other end of the high-voltage side of the shunt transformer T1 are connected to the position of an N point on a railway traction network return line in parallel;
the direct current sides of the two groups of single-phase fully-controlled bridges are connected with the series-parallel connection type energy storage smoothing capacitor group C in parallel, and the alternating current sides of the two groups of single-phase fully-controlled bridges are respectively connected with the low-voltage side of the shunt transformer T1 and the low-voltage side of the series transformer T2 after passing through the LCR filter.
2. A control method of a railway traction network alternating-current deicing device is characterized by comprising the following steps: one end of the high-voltage side of a parallel transformer T1 and one end of the high-voltage side of a series transformer T2 of the alternating-current deicing device of the railway traction network are connected in parallel to the position of a P point at the tail end of a railway traction network circuit;
the other end of the high-voltage side of the series transformer T2 is connected with one end of a high-capacity high-voltage reactor L3, and the other end of the high-capacity high-voltage reactor L3 and the other end of the high-voltage side of the shunt transformer T1 are connected in parallel with the position of an N point on a return line of a railway traction network; the direct current sides of the two groups of single-phase full-control bridges H1 and H2 are connected with the series-parallel connection type energy storage smoothing capacitor bank C in parallel, and the alternating current side of the single-phase full-control bridge H1 is connected with the low-voltage side of the shunt transformer T1 after passing through the LCR filter 1; the alternating current side of the single-phase full-control bridge H2 is connected with the low-voltage side of the series transformer T2 after passing through the LCR filter 2;
the control method adopts a multi-component comprehensive pressure stabilization method and a capacity split injection method for control;
in the multi-component comprehensive voltage stabilization method, a series voltage stabilization loop is formed by using a single-phase fully controlled bridge H2, an LCR filter 2 and a series transformer T2 to perform direct-current voltage stabilization control on two ends of a series-parallel energy storage smoothing capacitor bank C; the single-phase full-control bridge H1, the LCR filter 1 and the shunt transformer T1 form a shunt voltage stabilizing loop, and the series voltage stabilizing loop and the shunt voltage stabilizing loop comprehensively perform direct-current voltage stabilization control;
in the capacity shunt injection method, a large-capacity high-voltage reactor L3 is connected to the two ends of P, N through a series transformer T2, and inductive reactive current flows into a traction network connection system; the single-phase full-control bridge H1 and the LCR filter 1 are connected to the two ends of P, N through a shunt transformer T1, and inductive reactive current is injected into a traction network system; and distributing the two parts of inductive reactive current according to the required ice melting current capacity.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111202817.3A CN113937705B (en) | 2021-10-15 | 2021-10-15 | Alternating-current ice melting device for railway traction network and control method thereof |
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| CN202111202817.3A CN113937705B (en) | 2021-10-15 | 2021-10-15 | Alternating-current ice melting device for railway traction network and control method thereof |
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| CN113937705B true CN113937705B (en) | 2023-02-24 |
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