CN106160542A - A kind of modularization multi-level converter physical simulating device with potential isolation - Google Patents
A kind of modularization multi-level converter physical simulating device with potential isolation Download PDFInfo
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- CN106160542A CN106160542A CN201510153424.6A CN201510153424A CN106160542A CN 106160542 A CN106160542 A CN 106160542A CN 201510153424 A CN201510153424 A CN 201510153424A CN 106160542 A CN106160542 A CN 106160542A
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Abstract
The present invention relates to a kind of modularization multi-level converter physical simulating device with potential isolation, physical simulating device includes the multiple submodule analogue units being arranged on submodule simulation board；Described submodule analogue unit includes power supply interface circuit, control circuit and the cascade submodule main circuit being sequentially connected with.The device that the present invention provides is capable of modularization multi-level converter valve physical simulating device Neutron module main circuit, submodule controller, record wave system system, cabinet, the multi-level potential isolation between screen cabinet, it is achieved between high electronegative potential, the safe and reliable operation between digitial controller and analog device；The potential isolation contradiction between direct current thousands of volt high voltage being formed after can solve the problem that single submodule 24V DC low-voltage power supply requirement and series connection.
Description
Technical field
The present invention relates to the potential isolation device of flexible DC power transmission, be specifically related to a kind of modular multilevel with potential isolation
Transverter physical simulating device.
Background technology
Based on the HVDC technology (VSC-HVDC) of voltage source converter have can to island with power, meritorious and reactive power is only
Vertical regulation, do not have commutation failure, be not required to reactive-load compensation, the advantages such as distance submarine cable transmission of electricity can be carried out.In recent years should
Type technology of transmission of electricity is theoretical and engineering construction is worldwide in the trend developing rapidly.On the basis of conventional, based on novel
The high voltage dc transmission technology of modular multilevel voltage source converter (Modular Multi-level Converter, MMC)
(MMC-HVDC) application in technical field of HVDC transmission is achieved, and at wind energy turbine set 20MVA flexible DC power transmission
Demonstration project puts into operation successfully, with having launched more massive urban electricity supply DC transmission system construction, tests in the urgent need to one
Demonstrate,prove control strategy and the Control protection system of this engineering, and the module of the potential isolation of the control strategy of valve-based electronics control system
Change multilevel converter physical simulating device.
Content of the invention
For the deficiencies in the prior art, it is an object of the invention to provide a kind of modularization multi-level converter thing with potential isolation
Reason analogue means, this device is capable of modularization multi-level converter valve physical simulating device Neutron module main circuit, submodule
Multi-level potential isolation between controller, cabinet, screen cabinet, it is achieved between high electronegative potential, digitial controller and analog device it
Between safe and reliable operation.
It is an object of the invention to use following technical proposals to realize:
The present invention provides a kind of modularization multi-level converter physical simulating device with potential isolation, and it thes improvement is that,
Described physical simulating device includes the submodule simulation board which is provided with submodule analogue unit；Described submodule analogue unit bag
Include power supply interface circuit, control circuit and the cascade submodule main circuit being sequentially connected with.
Further, the many pin plugs on described submodule simulation board connect with inlet wire and the outlet of cascade submodule main circuit respectively
Connect formation closed-loop path.
Further, described cascade submodule main circuit is made up of N number of sub module cascade；Described submodule includes breaker, crystalline substance
Brake tube, two IGBT, equalizing resistance and capacitor；Said two IGBT is in parallel with equalizing resistance and capacitor after connecting；Institute
State breaker, IGCT and down tube IGBT in parallel；Upper pipe IGBT emitter stage in two IGBT connects down tube IGBT source electrode；
The positive pole of described capacitor connects upper pipe IGBT colelctor electrode, and negative pole connects down tube IGBT emitter stage；Described upper pipe IGBT and under
The equal inverse parallel of pipe IGBT has diode.
Further, insulating power supply module for power supply is used between the upper pipe IGBT of described submodule and down tube IGBT；Work as submodule
When in, pipe IGBT shutoff and down tube IGBT are opened, described submodule does not provide DC voltage, and bridge arm current is from down tube IGBT
Or the circulation of antiparallel diode, capacitor is bypassed；When pipe IGBT upper in submodule opens and down tube IGBT turns off,
Described submodule does not provide DC voltage, and bridge arm current circulates from upper pipe IGBT or antiparallel diode, and capacitor is bypassed.
Further, described control circuit includes digital processing unit and the capacitance voltage detection electricity being connected respectively with digital processing unit
Road, module board state detection circuit and switch element driver circuit；Described digital processing unit be single-chip microcomputer, CPLD processor,
FPGA processor or DSP Processor；Described capacitance voltage testing circuit with two lead-in wires, by submodule capacitor voltage by than
Example reduces circuit, and the chip dies analog quantity input pin of call number WP is to gather voltage；Described module status testing circuit is used
State in detection sub-module simulation board；Described switch element driver circuit obtains derailing switch from the output pin of digital processing unit
Part IGBT and the control command of IGCT, by amplifying and nursing one's health, the control of output drive signal to IGBT and IGCT is drawn
Pin.
Further, described power supply interface circuit includes insulating power supply, optical fiber interface and application interface；Described optical fiber interface and should
It is all connected with the digital processing unit of control circuit with interface；Described insulating power supply is electric with the same switch of multiple submodules simulation board
Source provides plate to connect.
Further, the multiple submodule analogue units on described submodule simulation board carry out after integrated design integrated installation in
In converter valve electric shield cabinet, described converter valve electric shield cabinet, AC-DC converter and isolating transformer are sequentially connected with；Described
Isolating transformer is provided with the connection end being connected with electrical network.
Further, 0 current potential of the output of each corresponding 24V dc source of converter valve electric screen shielding cabinet described and converter valve
In electric screen shielding cabinet, the capacitor anode of the submodule that current potential is minimum connects；The input current potential of described 24V dc source is unsettled,
Each submodule is arrived in output；Insulating power supply module on each submodule inputs 0 and is connected with the output 0 of 24V power supply, described
The output of insulating power supply module 0 is connected with the negative pole of capacitor in each submodule module；220V isolating transformer is utilized to hold
Potential difference in load converter valve electric screen shielding cabinet, reduces 24V dc source and the potential difference in submodule；Described 24V direct current
Power supply is the highest less than 1000V with the potential difference in submodule.
Further, described isolating transformer uses the isolating transformer of single-phase adjustable no-load voltage ratio 1:1 winding method, exchanges 220V
Electric energy is delivered to the secondary side of described physical simulating device by power supply by magnetic coupling, cuts down secondary side higher hamonic wave and isolates secondary
The electric fault of side affects primary side.
Compared with immediate prior art, the excellent effect that the technical scheme of present invention offer has is:
How electric the modularization multi-level converter physical simulating device with potential isolation that the present invention provides, be capable of modularization
Flat converter valve physical simulating device Neutron module main circuit, submodule controller, record wave system system, cabinet, many between screen cabinet
Level potential isolation, it is achieved between high electronegative potential, the safe and reliable operation between digitial controller and analog device.
The modularization multi-level converter physical simulating device with potential isolation that the present invention provides, can solve the problem that single submodule
The potential isolation contradiction between direct current thousands of volt high voltage being formed after 24V DC low-voltage power supply requirement and series connection.
Brief description
Fig. 1 is the converter valve physical simulating device sub modular structure figure that the present invention provides；
Fig. 2 is the converter valve submodule simulation board layout that the present invention provides；
Fig. 3 is the Modularized multi-level converter sub-module electric hookup that the present invention provides；
Fig. 4 is that the converter valve electric shield cabinet that the present invention provides carries out electrical isolation by civil power AC220V and isolating transformer and shows
It is intended to.
Detailed description of the invention
Below in conjunction with the accompanying drawings the detailed description of the invention of the present invention is described in further detail.
The present invention provides a kind of modularization multi-level converter physical simulating device with potential isolation, described physical simulating device
Including the multiple submodule analogue units being arranged on submodule simulation board；Described submodule analogue unit includes being sequentially connected with
Power supply interface circuit, control circuit and cascade submodule main circuit.Multiple modules cascade on same board structure such as Fig. 1 institute
Show.The multi-level voltage source current converter MMC submodule that the integrated multiple equivalences of circuit board of multi-level voltage source current converter are reduced,
Many pin plugs on submodule simulation board are connected with cascade submodule main circuit by cascade submodule main circuit inlet wire, then
It is connected to many pin plugs formation closed-loop path by cascading submodule main circuit outlet.
Cascade submodule main circuit is made up of N number of sub module cascade；Described submodule includes breaker, IGCT, two IGBT
(S1 and S2), equalizing resistance (R1) and conduct can put into resectable polarized electrolytic capacitor (C)；Said two IGBT
After series connection in parallel with equalizing resistance and capacitor；Described breaker, IGCT and down tube IGBT are in parallel；In two IGBT
Upper pipe IGBT emitter stage connects down tube IGBT source electrode；The positive pole of described capacitor connects upper pipe IGBT colelctor electrode, and negative pole connects
Down tube IGBT emitter stage；Described upper pipe IGBT and the equal inverse parallel of down tube IGBT have diode D1 and D2.
Insulating power supply module for power supply is taked between the upper pipe IGBT of submodule and down tube IGBT；When pipe IGBT upper in submodule closes
Disconnected and when down tube IGBT is opened, described submodule does not provide DC voltage, and bridge arm current is from down tube IGBT or antiparallel two
Pole pipe circulation, capacitor is bypassed；When pipe IGBT upper in submodule opens and down tube IGBT turns off, described submodule is not
There is provided DC voltage, bridge arm current circulates from upper pipe IGBT or antiparallel diode, and capacitor is bypassed.
Converter valve submodule uses 1 controller control and the integrated form integral layout driving 1 submodule, and each FPGA is controlled
Make a half-bridge.Current potential owing to simulating each submodule board is different, needs by insulating power supply module from same power supply power taking,
Then main circuit is driven by isolation drive.
Control circuit includes digital processing unit and the capacitance voltage testing circuit being connected respectively, module board state with digital processing unit
Testing circuit and switch element driver circuit；Described digital processing unit be single-chip microcomputer, CPLD processor, FPGA processor or
DSP Processor.Above-mentioned capacitance voltage testing circuit passes through two short legs, and submodule capacitor voltage passing ratio is reduced circuit,
Introduce the analog input pin of numerical processor chip, carry out voltage acquisition.The operation principle of module status testing circuit and electricity
Hold voltage detecting circuit to be similar to.Switch element driver circuit obtains switching device IGBT and crystalline substance from the output pin of digital processing unit
The control command of brake tube, by amplifying and nursing one's health, the control pin of output drive signal to IGBT and IGCT.
Power supply interface circuit includes insulating power supply, optical fiber interface and application interface；Described optical fiber interface and application interface all with control
The digital processing unit of circuit connects；Described insulating power supply provides plate to be connected with the same Switching Power Supply of multiple submodules simulation board.
Submodule simulation board on multiple submodule analogue units carry out integrated design after integrated installation in converter valve electric shield
In cabinet, described converter valve electric shield cabinet, AC-DC converter and isolating transformer are sequentially connected with；Described isolating transformer accesses
Electrical network.Isolating transformer is the isolating transformer of single-phase adjustable no-load voltage ratio 1:1 winding method, and 220V AC power is passed through magnetic coupling
Electric energy is delivered to secondary side, and abatement secondary side higher hamonic wave simultaneously avoids the electric fault of secondary side to affect primary side.
Reach peak value in view of valve module voltage-to-ground during dynamic model platform simulation single-stage ground short circuit, and consider design margin, control
Circuit power supply and main circuit partial electric insulation request are for more than 5000V, it is desirable to submodule board main electricity when PCB design
Road and control circuit cloth separate office.
Cause cost to sharply increase owing to configuring the modular power source with high rupturing capacity on each submodule, be therefore adopted as every
The mode of individual screen cabinet configuration isolation transformer provides the isolating power of more than 10kV.
0 current potential of the output of each corresponding 24V dc source of the converter valve electric shield cabinet submodule minimum with current potential in screen cabinet
The negative pole of capacitor be connected.The input current potential of 24V dc source is unsettled, and modules is arrived in output.In each module
Having insulating power supply module, insulating power supply module inputs 0 and connects together with the output 0 of 24V power supply, insulating power supply module
Output 0 be connected with the negative pole of capacitor in each submodule module.So utilize 220V isolating transformer to undertake one to put down
Most potential differences in cabinet, 24V dc source is corresponding to the potential difference in submodule to be reduced, the highest less than 1000V.
Finally should be noted that: above example is only in order to illustrating that technical scheme is not intended to limit, although reference
The present invention has been described in detail by above-described embodiment, and those of ordinary skill in the field still can concrete to the present invention
Embodiment is modified or equivalent, and these are changed or equivalent without departing from any of spirit and scope of the invention,
All within the claims of the present invention that application is awaited the reply.
Claims (9)
1. a modularization multi-level converter physical simulating device with potential isolation, it is characterised in that described physical analogy
Device includes the submodule simulation board which is provided with submodule analogue unit；Described submodule analogue unit includes being sequentially connected with
Power supply interface circuit, control circuit and cascade submodule main circuit.
2. physical simulating device as claimed in claim 1, it is characterised in that the many pin plugs on described submodule simulation board
It is connected formation closed-loop path with inlet wire and the outlet of cascade submodule main circuit respectively.
3. physical simulating device as claimed in claim 1, it is characterised in that described cascade submodule main circuit is by N number of son
Module-cascade forms；Described submodule includes breaker, IGCT, two IGBT, equalizing resistance and capacitor；Said two
IGBT is in parallel with equalizing resistance and capacitor after connecting；Described breaker, IGCT and down tube IGBT are in parallel；Two IGBT
In upper pipe IGBT emitter stage connect down tube IGBT source electrode；The positive pole of described capacitor connects upper pipe IGBT colelctor electrode, negative pole
Connect down tube IGBT emitter stage；Described upper pipe IGBT and the equal inverse parallel of down tube IGBT have diode.
4. physical simulating device as claimed in claim 3, it is characterised in that the upper pipe IGBT of described submodule and down tube IGBT
Between use insulating power supply module for power supply；When pipe IGBT upper in submodule turns off and down tube IGBT opens, described submodule is not
There is provided DC voltage, bridge arm current circulates from down tube IGBT or antiparallel diode, and capacitor is bypassed；When in submodule
When upper pipe IGBT opens and down tube IGBT turns off, described submodule does not provide DC voltage, bridge arm current from upper pipe IGBT or
Antiparallel diode circulates, and capacitor is bypassed.
5. physical simulating device as claimed in claim 1, it is characterised in that described control circuit include digital processing unit and
Capacitance voltage testing circuit, module board state detection circuit and the switch element driver circuit being connected with digital processing unit respectively；Institute
Stating digital processing unit is single-chip microcomputer, CPLD processor, FPGA processor or DSP Processor；Described capacitance voltage detection electricity
Submodule capacitor voltage passing ratio, with two lead-in wires, is reduced circuit by road, and the chip analog input of call number WP draws
Pin is to gather voltage；Described module status testing circuit is for the state of detection sub-module simulation board；Described switch element drives
Circuit obtains the control command of switching device IGBT and IGCT from the output pin of digital processing unit, by amplifying and nursing one's health,
Output drive signal is to the control pin of IGBT and IGCT.
6. physical simulating device as claimed in claim 1, it is characterised in that described power supply interface circuit include insulating power supply,
Optical fiber interface and application interface；Described optical fiber interface and application interface are all connected with the digital processing unit of control circuit；Described isolation
Power supply provides plate to be connected with the same Switching Power Supply of multiple submodules simulation board.
7. physical simulating device as claimed in claim 1, it is characterised in that the multiple submodules on described submodule simulation board
Block analogue unit carry out integrated design after integrated installation in converter valve electric shield cabinet, described converter valve electric shield cabinet,
AC-DC converter and isolating transformer are sequentially connected with；Described isolating transformer is provided with the connection end being connected with electrical network.
8. physical simulating device as claimed in claim 7, it is characterised in that each converter valve electric screen shielding cabinet described is corresponding
0 current potential of output of the 24V dc source submodule minimum with current potential in converter valve electric screen shielding cabinet capacitor anode even
Connect；The input current potential of described 24V dc source is unsettled, and each submodule is arrived in output；Insulating power supply module on each submodule is defeated
Enter 0 to be connected with the output 0 of 24V power supply, the output of described insulating power supply module 0 and electric capacity in each submodule module
The negative pole of device connects；Utilize 220V isolating transformer to undertake the potential difference in converter valve electric screen shielding cabinet, reduce 24V direct current
Power supply and the potential difference in submodule；Described 24V dc source is the highest less than 1000V with the potential difference in submodule.
9. physical simulating device as claimed in claim 7, it is characterised in that described isolating transformer uses single-phase adjustable no-load voltage ratio
Electric energy is delivered to described physical simulating device by magnetic coupling by 220V AC power by the isolating transformer of 1:1 winding method
Secondary side, cuts down secondary side higher hamonic wave and isolates the electric fault of secondary side and affect primary side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510153424.6A CN106160542B (en) | 2015-04-02 | 2015-04-02 | Modularization multi-level converter physical simulation device with potential isolation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510153424.6A CN106160542B (en) | 2015-04-02 | 2015-04-02 | Modularization multi-level converter physical simulation device with potential isolation |
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| Publication Number | Publication Date |
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| CN106160542A true CN106160542A (en) | 2016-11-23 |
| CN106160542B CN106160542B (en) | 2020-03-06 |
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| CN201510153424.6A Active CN106160542B (en) | 2015-04-02 | 2015-04-02 | Modularization multi-level converter physical simulation device with potential isolation |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115372815A (en) * | 2022-08-29 | 2022-11-22 | 广东电网有限责任公司广州供电局 | Device, method and medium for testing closing and bouncing time of sub-module bypass switch |
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| CN106160542B (en) | 2020-03-06 |
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Address after: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant after: State Grid Corporation of China Applicant after: GLOBAL ENERGY INTERCONNECTION Research Institute Applicant after: CHINA-EPRI ELECTRIC POWER ENGINEERING Co.,Ltd. Applicant after: STATE GRID ZHEJIANG ELECTRIC POWER Co. Address before: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant before: State Grid Corporation of China Applicant before: STATE GRID SMART GRID Research Institute Applicant before: CHINA-EPRI ELECTRIC POWER ENGINEERING Co.,Ltd. Applicant before: STATE GRID ZHEJIANG ELECTRIC POWER Co. |
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