CN214756077U - Resonant converter, switch module thereof and direct-current power transmission system - Google Patents
Resonant converter, switch module thereof and direct-current power transmission system Download PDFInfo
- Publication number
- CN214756077U CN214756077U CN202022868555.1U CN202022868555U CN214756077U CN 214756077 U CN214756077 U CN 214756077U CN 202022868555 U CN202022868555 U CN 202022868555U CN 214756077 U CN214756077 U CN 214756077U
- Authority
- CN
- China
- Prior art keywords
- module
- switch
- resonant converter
- capacitor
- switching tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
The application provides a resonant converter and switch module, direct current transmission system thereof, whether control switch module inserts resonant converter's bridge arm structure through the side switch module among the switch module to this utilizes the redundant installation of a plurality of switch modules to arrange, makes resonant converter when one or several switch modules break down, can directly switch over reserve switch module under the condition that does not influence normal work, replaces the switch module of damage. The technical problems that a switch module of a modular multilevel converter in the prior art cannot work normally when damaged, so that a direct-current power transmission system is poor in reliability and low in safety are solved, and the technical effects of ensuring the fault-tolerant rate of a resonant converter, prolonging the service life of the resonant converter and improving the safety of a direct-current power transmission network system are achieved.
Description
Technical Field
The application relates to the field of power transmission, in particular to a resonant converter, a switch module of the resonant converter and a direct-current transmission system of the resonant converter.
Background
Direct Current (HVDC) transmission technology began in the 20 th century and has undergone three technological innovations. Compared with the traditional alternating current power transmission and distribution technology, the novel direct current power transmission and distribution technology has wide application prospect in the fields of large-capacity remote power transmission, direct current intelligent micro-grid, high-speed rail transit, marine observation stations and the like with unique advantages. The dc converter is one of the key technologies in the field of dc power transmission and distribution. The modular multilevel converter technology is increasingly applied to the field of direct current transmission due to the advantages of high reliability and low loss.
At present, a plurality of switch modules of a modular multilevel converter are used in series as key parts for converting direct current into sine or cosine wave alternating current, and a plurality of switch modules exist in each converter by utilizing the principle that step waves approach sine waves.
However, in the prior art, the switch modules are generally soldered on the circuit board, and after the converter is installed, if any one switch module is irreversibly damaged, the whole converter cannot normally operate, that is, the modular multilevel converter in the prior art cannot normally operate when a limited number of switch modules have faults, so that the fault tolerance rate is low, and the direct current transmission system has poor reliability and low safety.
SUMMERY OF THE UTILITY MODEL
The application provides a resonant converter and a switch module thereof, and a direct current transmission system, which are used for solving the technical problems that the reliability of the direct current transmission system is poor and the safety is lower because the switch module of a modular multilevel converter in the prior art cannot maintain normal work when being damaged.
In a first aspect, the present application provides a switching module of a resonant converter, comprising:
the circuit comprises a first switching tube, a second switching tube, a capacitor and a side-opening module, wherein the first switching tube and the second switching tube are connected in series to form a half bridge arm structure, the anode of the capacitor is connected with the input end of the first switching tube, the cathode of the capacitor is connected with the output end of the second switching tube, the output end of the first switching tube is a high-potential end of the switching module, and the output end of the second switching tube is a low-potential end of the switching module;
the input end of the bypass module is connected with the high-potential end, the output end of the bypass module is connected with the low-potential end, and the bypass module is used for controlling the state of a connecting switch in the switch module and the modular multilevel resonant converter.
In one possible design, the bypass module includes a third switch tube, an input end of the third switch tube is connected with the high potential end, and an output end of the third switch tube is connected with the low potential end.
Optionally, the switch module further includes: a follow current module; the input end of the follow current module is connected with the high potential end, the output end of the follow current module is connected with the anode of the capacitor, and the follow current module is used for providing a follow current loop for the capacitor.
In one possible design, the freewheel module includes a freewheel diode having an input connected to the high potential terminal and an output connected to the positive terminal of the capacitor.
Optionally, the freewheeling diode comprises at least two diodes connected in parallel, the input terminal of the diode being connected to the high potential terminal and the output terminal of the diode being connected to the anode of the capacitor.
Optionally, the first switching tube includes at least two power switching tubes connected in parallel.
Optionally, the second switch tube includes at least two power switch tubes connected in parallel.
Optionally, the third switching tube includes at least two power switching tubes connected in parallel.
Optionally, the power switch tube includes: insulated gate bipolar transistors IGBTs and metal-oxide semiconductor field effect transistors MOSFETs.
In a second aspect, the present application provides a resonant converter comprising:
the voltage-sharing module, the upper bridge arm module, the lower bridge arm module, the oscillation module, the transformer and the rectification module;
the voltage-sharing module comprises a first voltage-sharing capacitor and a second voltage-sharing capacitor which are connected in series;
the upper bridge arm module is connected with the lower bridge arm module in series;
the first end of the oscillation module is connected between the first voltage-sharing capacitor and the second uniform capacitor, the second end of the oscillation module is connected between the upper bridge arm module and the lower bridge arm module, and the oscillation module is connected with the transformer in series;
the rectification module is connected with the secondary stage of the transformer;
the upper leg module and/or the lower leg module comprises at least one possible switching module according to any of the first aspects.
In one possible design, the upper leg module and/or the lower leg module further comprises: bridge arm inductance.
Optionally, the oscillation module includes an LC oscillation circuit, and the upper bridge arm module, the lower bridge arm module, the oscillation circuit, and the transformer form an LLC oscillation circuit structure, or the bridge arm inductor, the oscillation circuit, and the transformer form an LLC oscillation circuit structure.
Optionally, the upper bridge arm module and/or the lower bridge arm module at least include two series switch modules, and the number of the series switch modules is greater than or equal to the number of the series switch modules required by the modular multilevel resonant converter during normal operation.
In a third aspect, the present application provides a direct current power transmission system comprising:
the resonant converter comprises a power transmission end, a low-voltage power utilization end and any one of the possible resonant converters in the second aspect, wherein after the direct current output by the power transmission end is reduced by the resonant converter, the resonant converter outputs the low-voltage direct current to supply power to the low-voltage power utilization end.
The application provides a resonant converter and switch module, direct current transmission system thereof, whether control switch module inserts resonant converter's bridge arm structure through the side switch module among the switch module to this utilizes the redundant installation of a plurality of switch modules to arrange, makes resonant converter when one or several switch modules break down, can directly switch over reserve switch module under the condition that does not influence normal work, replaces the switch module of damage. The technical problems that a switch module of a modular multilevel converter in the prior art cannot work normally when damaged, so that a direct-current power transmission system is poor in reliability and low in safety are solved, and the technical effects of ensuring the fault-tolerant rate of a resonant converter, prolonging the service life of the resonant converter and improving the safety of a direct-current power transmission network system are achieved.
Drawings
In order to more clearly illustrate the technical solutions in the present application or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.
Fig. 1 is a schematic structural diagram of a first MMC switch module SM provided in the present application;
fig. 2 is a schematic structural diagram of a second MMC switch module SM provided in the present application;
fig. 3 is a schematic structural diagram of a third MMC switch module SM provided in the present application;
fig. 4 is a schematic structural diagram of a fourth MMC switch module SM provided in the present application;
FIGS. 5a-5d are schematic diagrams of current loops in the MMC switch module SM provided herein;
fig. 6 is a schematic structural diagram of an MMC modular multilevel resonant converter provided in the present application;
fig. 7 is a schematic structural diagram of another MMC modular multilevel resonant converter provided in the present application;
fig. 8 is a schematic structural diagram of a high-voltage direct-current power transmission system provided by the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments, including but not limited to combinations of embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any inventive step are within the scope of the present application.
The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The following explains and describes terms related to embodiments of the present application.
MMC (Modular Multilevel converter): the novel multilevel converter structure inherits the advantages of a cascade multilevel structure, replaces an independent power supply with the charging capacitor, overcomes the defects that two levels and three levels are difficult to develop to the multilevel again, and reduces the stress required to be born by each switch module, including voltage and/or current. The MMC is formed by cascading a plurality of Sub-modules (SMs) with the same structure. The sub-module structure can be divided into half H-bridge type, full H-bridge type and double-clamping type sub-module type. The half H-bridge type sub-module is most commonly applied to the current engineering, but the half H-bridge type sub-module does not have direct current fault ride-through capability and needs to be cut off by means of an alternating current breaker.
An LC resonance circuit: is a circuit comprising an inductor (denoted by the letter L) and a capacitor (denoted by the letter C) connected together in series. The circuit may be used as an electrical resonator to store energy that oscillates when the circuit resonates. Resonance is also referred to as resonance.
LLC resonant circuit: is a resonant circuit for achieving constant output voltage by controlling the switching frequency (frequency adjustment), comprising two inductors (denoted by letters Lr and Lm) and a capacitor (denoted by letter C) and. It has the advantages that: zero-voltage switching-on (ZVS) of two main switching tubes (such as MOS tubes) on the primary side of the transformer and zero-current switching-off (ZCS) of a secondary side rectifier diode are realized, and through a soft switching technology, the switching loss of a power supply can be reduced, and the efficiency and the power density of the power converter are improved.
Compared with the traditional alternating current power transmission and distribution technology, the novel direct current power transmission and distribution technology (high voltage direct current (HVDC) power transmission technology) has wide application prospect in the fields of large-capacity remote power transmission, direct current intelligent micro-grid, high-speed rail transit, ocean observation stations and the like with unique advantages. The high-voltage direct-current converter is one of key technologies in the field of direct-current power transmission and distribution. The modular multilevel resonant converter MMC technology is increasingly applied to the field of high-voltage direct-current power transmission due to the advantages of high reliability and low loss.
At present, in the prior art, a switch module SM of a modular multilevel converter serves as a key component for converting direct current into sine or cosine wave alternating current, a plurality of switch modules SM are cascaded in series, a plurality of charging capacitors are used for generating step waves to approach sine waves, and a plurality of switch modules SM exist in each converter. And the number of switching modules SM is equal to the number of steps or levels.
However, in the prior art, the switch modules SM are generally soldered on a circuit board, and after the converter is mounted, if any one of the switch modules is irreversibly damaged, the whole converter cannot normally operate, that is, the modular multilevel converter in the prior art cannot normally operate when a limited number of switch modules have faults, so that the fault tolerance rate is low, and the high-voltage direct-current transmission system has poor reliability and low safety.
In order to solve the above problems, the present application provides a novel switch module of a modular multilevel converter, where the switch module includes a bypass module, and the bypass module is used to control whether the switch module is connected to a resonant converter, so that switch modules more than the number of switch modules required for normal operation can be arranged in the resonant converter, the redundant switch modules can be used as a backup, when a part of the switch modules is damaged, the backup switch modules can be connected to a working circuit of the resonant converter through the bypass module to replace the damaged switch modules, and the damaged switch modules can cut off the working circuit of the resonant converter through the bypass module to ensure that the resonant converter cannot be affected by the damaged switch modules.
Fig. 1 is a schematic structural diagram of a first MMC switch module SM provided in the present application. As shown in fig. 1, the switch module includes: the circuit comprises a first switch tube 101, a second switch tube 102, a capacitor 103 and a bypass switch module 104, wherein the first switch tube 101 and the second switch tube 102 are connected in series to form a half-bridge arm structure, the anode of the capacitor 103 is connected with the input end of the first switch tube 101, the cathode of the capacitor 103 is connected with the output end of the second switch tube 102, the output end of the first switch tube 101 is the high-potential end of the switch module, and the output end of the second switch tube 102 is the low-potential end of the switch module;
the input end of the bypass module 104 is connected to the high potential end, the output end of the bypass module 104 is connected to the low potential end, and the bypass module 104 is used for controlling the state of the switch module and the connection switch in the modular multilevel resonant converter.
It should be noted that the first switch tube 101 and the second switch tube 102 include a power switch tube and a diode connected in anti-parallel therewith. In one possible embodiment, the power switching tube and the diode connected in anti-parallel therewith are integrated in a single component. The capacitor 103 comprises at least one individually packaged capacitor component.
Optionally, in order to reduce the current endurance requirement of the power switch tube, the first switch tube 101 and/or the second switch tube 102 may be formed by connecting a plurality of (at least two) power switch tubes in parallel. In order to reduce the requirement for the withstand voltage of the power switch tube, the first switch tube 101 and/or the second switch tube 102 may be formed by connecting a plurality of (at least two) power switch tubes in series. It can be understood that, in order to enable the application range of the switch module to be adapted to the requirements of various withstand voltage and current values, a plurality of power switching tubes may be in series-parallel connection, and the power switching tubes are dynamically converted into a parallel or series connection structure by dynamically controlling the power switching tubes to be normally open or normally closed.
The embodiment provides a switch module of a resonant converter, wherein a side switch module in the switch module is used for controlling whether the switch module is connected to a bridge arm structure of the resonant converter, so that the redundant installation arrangement of a plurality of switch modules is utilized, when one or more switch modules of the resonant converter fails, the standby switch module can be directly switched without influencing normal operation, and the damaged switch module is replaced. The technical problems that a high-voltage direct-current power transmission system is poor in reliability and low in safety due to the fact that a switch module of a modular multilevel converter cannot work normally when damaged in the prior art are solved, and the technical effects that the fault-tolerant rate of a resonant converter is guaranteed, the service life of the resonant converter is prolonged, and the safety of a direct-current high-voltage power transmission network system is improved are achieved.
In one possible design, the bypass module 104 includes a third switch, an input terminal of which is connected to the high potential terminal, and an output terminal of which is connected to the low potential terminal.
Fig. 2 is a schematic structural diagram of a second MMC switch module SM provided in the present application. As shown in fig. 2, the switch module includes: the circuit comprises a first switching tube 201, a second switching tube 202, a capacitor 203 and a third switching tube 204, wherein the first switching tube 201 and the second switching tube 202 are connected in series to form a half-bridge arm structure, the anode of the capacitor 203 is connected with the input end of the first switching tube 201, the cathode of the capacitor 203 is connected with the output end of the second switching tube 202, the output end of the first switching tube 201 is a high-potential end of a switching module, and the output end of the second switching tube 202 is a low-potential end of the switching module;
the input end of the third switch tube 204 is connected with the high potential end, the output end of the third switch tube 204 is connected with the low potential end, and the third switch tube 204 is used for controlling the connection switch state of the switch module and the modular multilevel resonant converter.
The third switch 204 in the above embodiment is the simplest implementation structure of the bypass module 104, and a person skilled in the art can connect other components in parallel, such as a reverse parallel diode, according to the actual situation to avoid the situation that the function of controlling access of the bypass module cannot be realized when the diode in the third switch is damaged.
Optionally, the first switch tube 201, and/or the second switch tube 202, and/or the third switch tube 204 includes at least two power switch tubes connected in parallel.
The power switching tube includes: insulated gate bipolar transistors IGBTs and metal-oxide semiconductor field effect transistors MOSFETs.
The embodiment provides a switch module of a resonant converter, wherein whether the switch module is connected to a bridge arm structure of the resonant converter is controlled through a side switch module, namely a third switch tube, in the switch module, so that when one or more switch modules of the resonant converter fails, the standby switch module can be directly switched without affecting normal operation by using redundant installation arrangement of a plurality of switch modules, and the damaged switch module is replaced. The technical problems that a high-voltage direct-current power transmission system is poor in reliability and low in safety due to the fact that a switch module of a modular multilevel converter cannot work normally when damaged in the prior art are solved, and the technical effects that the fault-tolerant rate of a resonant converter is guaranteed, the service life of the resonant converter is prolonged, and the safety of a direct-current high-voltage power transmission network system is improved are achieved.
In one possible design, in order to still charge the capacitor when the body diode of the first switch tube (i.e. the diode connected in anti-parallel with the power switch tube or the body diode contained in the power switch tube) is damaged, or to reduce the current in the body diode, so as to reduce the power loss of the first switch tube and reduce the heat generation of the first switch tube, a freewheeling module is connected in parallel to the first switch tube in the switch module, as shown in fig. 3 in particular.
Fig. 3 is a schematic structural diagram of a third MMC switch module SM provided in the present application. As shown in fig. 3, the switch module includes: the circuit comprises a first switching tube 301, a second switching tube 302, a capacitor 303, a bypass switch module 304 and a follow current module 305, wherein the first switching tube 301 and the second switching tube 302 are connected in series to form a half bridge arm structure, the anode of the capacitor 303 is connected with the input end of the first switching tube 301, the cathode of the capacitor 303 is connected with the output end of the second switching tube 302, the output end of the first switching tube 301 is a high potential end of the switching module, and the output end of the second switching tube 302 is a low potential end of the switching module;
the input end of the bypass module 304 is connected with the high potential end, the output end of the bypass module 304 is connected with the low potential end, and the bypass module 304 is used for controlling the connection switch state of the switch module and the modular multilevel resonant converter;
the input of the freewheel module 305 is connected to the high potential terminal and the output of the freewheel module is connected to the anode of the capacitor 303, the freewheel module being arranged to provide a freewheel loop to the capacitor 303.
Optionally, the freewheel module 305 comprises a freewheel diode having an input connected to the high potential terminal and an output connected to the anode of the capacitor. As shown in particular in fig. 4.
Fig. 4 is a schematic structural diagram of a fourth MMC switch module SM provided in the present application. As shown in fig. 4, the switch module includes: the circuit comprises a first switching tube 401, a second switching tube 402, a capacitor 403, a third switching tube 404 and a freewheeling diode 405, wherein the first switching tube 401 and the second switching tube 402 are connected in series to form a half-bridge arm structure, the anode of the capacitor 403 is connected with the input end of the first switching tube 401, the cathode of the capacitor 403 is connected with the output end of the second switching tube 402, the output end of the first switching tube 401 is a high-potential end of a switching module, and the output end of the second switching tube 402 is a low-potential end of the switching module;
the input end of the third switch tube 404 is connected with the high potential end, the output end of the third switch tube 404 is connected with the low potential end, and the third switch tube 404 is used for controlling the connection switch state of the switch module and the modular multilevel resonant converter;
a freewheeling diode 405 having an input connected to the high potential terminal and an output connected to the anode of capacitor 403 is used to provide a freewheeling circuit for capacitor 403.
Optionally, in order to reduce the current endurance requirement of each freewheeling diode, the freewheeling diode comprises at least two parallel diodes, the input end of the diode is connected with the high potential end, and the output end of the diode is connected with the anode of the capacitor. Similarly, if the requirement of the withstand voltage value is reduced, the freewheeling diode comprises at least two diodes connected in series. It is understood that the present application may also include the case where at least three diodes are connected in series-parallel.
For the purpose of specific description, the specific functions of the bypass module and the freewheel module will be described in detail with reference to fig. 5a-5 d.
When the MMC resonant converter works normally, the switch module can only be in a switching-in state or a switching-off state, and a locking state is not allowed to occur when the MMC resonant converter works normally. And when the switch module causes unrecoverable faults due to external factors, such as the second switch tube is damaged, the switch module can be quickly and reliably cut off from the whole MMC resonant converter system through the side-opening module, the redundancy standby of the switch module is realized, the switch module is not required to be replaced by stopping, and meanwhile, when the first switch tube is damaged due to the fault of the switch module, the system can follow current through the follow current module, so that the fault-tolerant capability of the system is improved.
Fig. 5a-5d are schematic diagrams of current loops in the MMC switch module SM provided herein. As shown in fig. 5a-5b, when the switch module works in the cut-off state, normally, the cutting off of the capacitor 403 in the switch module is realized by closing the second switch tube 402 in the switch module, but when the power device (IGBT or MOSFET) in the second switch tube 402 is damaged (dashed line component in fig. 5 a), the cutting off of the sub-module can be realized by the bypass module, the capacitor 403 of other switch modules of the MMC resonant converter passes through the power device in the third switch tube 404 when being charged, and the current working loop of the switch module is as shown in fig. 5 a.
When the body diode or the anti-parallel diode of the power device in the second switch tube 402 is damaged (the dashed line component in fig. 5 b), the current passes through the body diode or the anti-parallel diode of the power device of the third switch tube 404 when the capacitor 403 of the other switch module of the MMC resonant converter discharges, and the module current working loop is as shown in fig. 5 b.
When the switch module is in the on state and the capacitor 403 is charged, the freewheeling circuit is required to charge the switch module capacitor. In case of a breakdown of the body diode or the anti-parallel diode of the power device in the first switching tube 401 (dashed line components in fig. 5 c), a current may charge the capacitance 403 of the switching module via the freewheeling diode 405, as shown in fig. 5 c.
When the switch module is in the on state and the capacitor 403 is discharged, the freewheeling circuit is required to discharge the switch module capacitor. In case of a breakdown of the body diode or the anti-parallel diode of the power device in the first switching tube 401 (dashed line component in fig. 5 d), a current may discharge the capacitor 403 of the switching module through the power device in the first switching tube 401, as shown in fig. 5 d.
Fig. 6 is a schematic structural diagram of an MMC modular multilevel resonant converter provided in the present application. As shown in fig. 6, the resonant converter 600 includes:
the voltage-sharing module 601, the upper bridge arm module 602, the lower bridge arm module 603, the oscillation module 604, the transformer 605 and the rectification module 606;
the voltage-sharing module comprises a first voltage-sharing capacitor 6011 and a second voltage-sharing capacitor 6012 which are connected in series;
the upper bridge arm module 602 is connected in series with the lower bridge arm module 603;
a first end of the oscillation module 604 is connected between the first equalizing capacitor 6011 and the second equalizing capacitor 6012, a second end of the oscillation module 604 is connected between the upper arm module 602 and the lower arm module 603, and the oscillation module 604 is connected in series with the transformer 605;
the rectification module 606 is connected with the secondary stage of the transformer 605;
the upper leg module 602 and/or the lower leg module 603 comprise at least one of any of the possible switch modules SM in the respective MMC switch module SM embodiments described above.
Fig. 7 is a schematic structural diagram of another MMC modular multilevel resonant converter provided in the present application. As shown in fig. 7, the resonant converter 700 includes:
a voltage equalizing module 701, an upper bridge arm module 702, a lower bridge arm module 703, an oscillation module 704, a transformer 705 and a rectifying module 706;
the voltage-sharing module comprises a first voltage-sharing capacitor 7011 and a second voltage-sharing capacitor 7012 which are connected in series;
the upper bridge arm module 702 is connected in series with the lower bridge arm module 703;
the upper leg module 702 includes: an upper bridge arm inductance LP and a plurality of switch modules SM;
the lower leg module 703 includes: a lower bridge arm inductance LN and a plurality of switch modules SM;
a first end of the oscillation module 704 is connected between the first equalizing capacitor 7011 and the second equalizing capacitor 7012, a second end of the oscillation module 704 is connected between the upper bridge arm module 702 and the lower bridge arm module 703, and the oscillation module 704 is connected in series with the transformer 705;
the rectifier module 706 is connected with the secondary stage of the transformer 705;
the rectifying module 706 is an H-bridge rectifying module;
the oscillation module includes: the LC oscillating circuit, the upper bridge arm module, the lower bridge arm module, the oscillating circuit and the transformer form an LLC oscillating circuit structure, or the bridge arm inductor, the oscillating circuit and the transformer form an LLC oscillating circuit structure.
It should be noted that the number of the switch modules SM connected in series is greater than or equal to the number of the series switch modules required by the MMC resonant converter in normal operation. Therefore, the redundancy of the switch modules in the resonant converter can be realized, when one or more switch modules are damaged, the damaged switch modules can be directly replaced by the redundant switch modules without shutdown replacement, and the fault tolerance rate and the working reliability of the resonant converter are improved.
Fig. 8 is a schematic structural diagram of a high-voltage direct-current power transmission system provided by the present application. As shown in fig. 8, the high voltage direct current transmission system comprises: a high voltage transmission terminal 801, a low voltage power utilization terminal 802, and a resonant converter 803, the high voltage transmission terminal 801 can be understood as a circuit structure for generating high voltage direct current, the low voltage power utilization terminal includes a plurality of low voltage power utilization devices, and the high voltage transmission terminal 801 is located at a relatively long distance, such as several tens of kilometers or several hundreds of kilometers, from the low voltage power utilization terminal 802. The resonant converter 803 is any one of the possible resonant converters shown in fig. 6 or fig. 7.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.
Claims (13)
1. A switching module for a resonant converter, comprising:
the circuit comprises a first switching tube, a second switching tube, a capacitor and a side-switch module, wherein the first switching tube and the second switching tube are connected in series to form a half bridge arm structure, the positive electrode of the capacitor is connected with the input end of the first switching tube, the negative electrode of the capacitor is connected with the output end of the second switching tube, the output end of the first switching tube is a high-potential end of the switching module, and the output end of the second switching tube is a low-potential end of the switching module;
the input end of the bypass module is connected with the high potential end, the output end of the bypass module is connected with the low potential end, and the bypass module is used for controlling the connection switch state of the switch module and the modular multilevel resonant converter.
2. The switch module of claim 1, wherein said bypass module comprises a third switch tube, an input terminal of said third switch tube being connected to said high potential terminal, an output terminal of said third switch tube being connected to said low potential terminal.
3. The switch module of claim 1, further comprising: a follow current module; the input end of the follow current module is connected with the high potential end, the output end of the follow current module is connected with the anode of the capacitor, and the follow current module is used for providing a follow current loop for the capacitor.
4. A switch module as claimed in claim 3, wherein said freewheel module comprises a freewheel diode, the input terminal of said freewheel diode being connected to said high potential terminal and the output terminal of said freewheel diode being connected to the positive pole of said capacitor.
5. The switch module of claim 4, wherein said freewheeling diode comprises at least two diodes connected in parallel, the input of said diode being connected to said high potential terminal and the output of said diode being connected to the anode of said capacitor.
6. The switch module according to any one of claims 1-5, characterized in that the first switching tube and/or the second switching tube comprises at least two parallel power switching tubes.
7. The switch module according to claim 2, characterized in that the first switching tube, and/or the second switching tube, and/or the third switching tube comprises at least two parallel power switching tubes.
8. The switch module of claim 7, wherein the power switching tube comprises: insulated gate bipolar transistors IGBTs and metal-oxide semiconductor field effect transistors MOSFETs.
9. A resonant converter, comprising:
the voltage-sharing module, the upper bridge arm module, the lower bridge arm module, the oscillation module, the transformer and the rectification module;
the voltage-sharing module comprises a first voltage-sharing capacitor and a second voltage-sharing capacitor which are connected in series;
the upper bridge arm module is connected with the lower bridge arm module in series;
the first end of the oscillation module is connected between the first voltage-sharing capacitor and the second voltage-sharing capacitor, the second end of the oscillation module is connected between the upper bridge arm module and the lower bridge arm module, and the oscillation module is connected with the transformer in series;
the rectification module is connected with the secondary stage of the transformer;
the upper leg module and/or the lower leg module comprises at least one switching module according to any one of claims 1 to 8.
10. The resonant converter according to claim 9, characterized in that the upper leg module and/or the lower leg module further comprises: bridge arm inductance.
11. The resonant converter according to claim 10, wherein the oscillating module comprises an LC oscillating circuit, and the leg inductors, the oscillating circuit and the transformer form an LLC oscillating circuit structure.
12. The resonant converter according to any one of claims 9 to 11, characterized in that at least two of the upper leg modules and/or the lower leg modules comprise series switch modules, and the number of the series switch modules is greater than or equal to the number of series switch modules required by the modular multilevel resonant converter during normal operation.
13. A hvdc transmission system comprising the resonant converter of any one of claims 9-12, a high voltage transmission terminal and a low voltage power utilization terminal, wherein the high voltage dc power output from the high voltage transmission terminal is stepped down by the resonant converter, and the resonant converter outputs a low voltage dc power to power the low voltage power utilization terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022868555.1U CN214756077U (en) | 2020-12-03 | 2020-12-03 | Resonant converter, switch module thereof and direct-current power transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022868555.1U CN214756077U (en) | 2020-12-03 | 2020-12-03 | Resonant converter, switch module thereof and direct-current power transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214756077U true CN214756077U (en) | 2021-11-16 |
Family
ID=78618955
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022868555.1U Active CN214756077U (en) | 2020-12-03 | 2020-12-03 | Resonant converter, switch module thereof and direct-current power transmission system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214756077U (en) |
-
2020
- 2020-12-03 CN CN202022868555.1U patent/CN214756077U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Pang et al. | Research on key technology and equipment for Zhangbei 500kV DC grid | |
| Ruiz et al. | Surveying solid-state transformer structures and controls: Providing highly efficient and controllable power flow in distribution grids | |
| Chen et al. | A step-up resonant converter for grid-connected renewable energy sources | |
| CN107204626B (en) | LCC-MMC (lower control center-Modular multilevel converter) staggered hybrid bipolar direct-current power transmission system | |
| US20130201725A1 (en) | Resonant circuit and resonant dc/dc converter | |
| CN109256951B (en) | Direct-current voltage conversion device and control method thereof | |
| WO2021218227A1 (en) | Modular capacitor commutated converter and method | |
| CN107592017B (en) | DC-DC converter and control method | |
| US11967859B2 (en) | Power factor correction circuit, power factor correction assembly and on-line uninterruptible power supply comprising same | |
| Chen et al. | Indirect input-series output-parallel DC–DC full bridge converter system based on asymmetric pulsewidth modulation control strategy | |
| CN107612408B (en) | Energy storage converter and energy storage system | |
| CN101022247A (en) | Half bridge resonant transformer | |
| Xu et al. | A novel hybrid line commutated converter based on IGCT to mitigate commutation failure for high-power HVdc application | |
| Purgat et al. | Low-voltage dc system building blocks: Integrated power flow control and short circuit protection | |
| Hu et al. | Intelligent DC-DC converter based substations enable breakerless MVDC grids | |
| Aldosari et al. | A High-Efficiency Isolated PFC AC–DC Topology with Reduced Number of Semiconductor Devices | |
| CN214756077U (en) | Resonant converter, switch module thereof and direct-current power transmission system | |
| CN202127364U (en) | Three-level resonant converter for primary edge clamping of resonant capacitor with transformer | |
| CN214154020U (en) | 10kV series active voltage regulating system | |
| CN112350569B (en) | Isolated resonant switch capacitor converter | |
| CN113839370A (en) | Voltage regulation and control type oscillation type direct current breaker and control method thereof | |
| CN111146962B (en) | Compact power electronic transformer for energy Internet and control method thereof | |
| CN112564496A (en) | Resonant converter, control method and device, power transmission system and storage medium | |
| Verbytskyi et al. | Operation and Design of Series-Resonant Current-Source Full-Bridge DC-DC Converter | |
| Jakka et al. | Implementation of flexible large power transformers using modular solid state transformer topologies enabled by sic devices |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |