CN105281314A - DC power transmission system based on modularized multi-level converter unit - Google Patents
DC power transmission system based on modularized multi-level converter unit Download PDFInfo
- Publication number
- CN105281314A CN105281314A CN201510657389.1A CN201510657389A CN105281314A CN 105281314 A CN105281314 A CN 105281314A CN 201510657389 A CN201510657389 A CN 201510657389A CN 105281314 A CN105281314 A CN 105281314A
- Authority
- CN
- China
- Prior art keywords
- mmc
- transmission system
- elementary layer
- level converter
- converter unit
- 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.)
- Pending
Links
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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Rectifiers (AREA)
Abstract
The invention relates to a DC power transmission system based on a modularized multi-level converter unit. The system is formed by M by N MMCs and (M+1) buses, wherein every N MMCs form a unit layer, and M unit layers are formed in total. The N MMCs in each unit layer are connected in parallel between a positive bus and a negative bus. The M unit layers are connected in series successively, and each MMC in every unit layer is connected to the positive bus which is the negative bus connected with the MMCs in the previous unit layer. The intersecting redundant structure of the system solves the problem of poor fault-tolerant capability of the system.
Description
Technical field
The present invention relates to a kind of DC transmission system based on modularization multi-level converter unit, belong to the technical field of flexible direct current power transmission and distribution.
Background technology
Along with the development of power technology, voltage source converter high voltage direct current transmission based on all-controlling power electronics device, namely Technology of HVDC based Voltage Source Converter because of its can independently carry out gaining merit, idle control, and without commutation failure risk, can be subject to favoring widely and application for plurality of advantages such as passive island with power in addition.Wherein, based on the flexible direct current power transmission system of modularization multi-level converter (MMC), due to its have switching frequency compared with low, switching loss is little, without the need to alternating current filter and the advantage such as autgmentability is strong, become the main trend of flexible direct current power transmission system.
But in the process of system cloud gray model, MMC unit easily breaks down, such as: the IGBT element in MMC unit due to its voltage, current overload ability more weak, too high voltage, current-rising-rate just may cause it to damage.Especially, MMC is mainly used in mesohigh field, generally for the demand meeting Large Copacity transmission, and the MMC quantity that bus is connected is too much, and control signal transmission quantity is large, and just compare and submodule can be caused to break down, system can not normally be run.Therefore, the faults-tolerant control ability improving the flexible direct current power transmission system of modularization multi-level converter is extremely necessary.At present, frequently by arranging redundant module to ensure the stability of system cloud gray model in prior art, when string in system has multiple submodule, this will be higher to the requirement of system failure faults-tolerant control, if the unreasonable structure that redundant module is arranged in DC transmission system, this will cause the fault-tolerant ability of DC transmission system poor, the stability that influential system runs.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, propose a kind of DC transmission system based on modularization multi-level converter unit, utilize the crossing redundancy structure of this system to solve the problem of the fault-tolerant ability difference of this DC transmission system.
The present invention is achieved by following scheme:
Based on a DC transmission system for modularization multi-level converter unit, this DC transmission system is made up of M × N number of MMC and M+1 bar bus; Wherein, every N number of MMC forms an elementary layer, forms M elementary layer altogether; N number of MMC in each elementary layer is connected in parallel between a positive bus-bar and a negative busbar; M described elementary layer is connected successively, the negative busbar that the MMC that the positive bus-bar that namely in each elementary layer, each MMC connects is an elementary layer connects; The positive bus-bar that MMC in first module layer connects is provided with the positive pole of described DC transmission system, and the negative busbar that each MMC in last elementary layer connects is provided with the negative pole of described DC transmission system.
Further, described MMC is three-phase six bridge arm structure, and each brachium pontis is made up of according to the ratio cascade of setting half-bridge submodule and full-bridge submodule, and each brachium pontis is also in series with brachium pontis reactor.
Further, described MMC also comprises: converter transformer and softly open loop.
The present invention's beneficial effect is compared to the prior art:
At present, the demand of the flexible direct current power transmission system demand fulfillment Large Copacity output of modularization multi-level converter, therefore, on the transmission bus of transmission of electricity, often string has multiple MMC submodule, and this just requires higher to the failure tolerant control ability of system.DC transmission system of the present invention by several MMC are formed an elementary layer, be parallel to one between positive bus-bar and negative busbar, as an elementary layer of system, again several elementary layer head and the tail successively series connection are obtained, the similar matrix form combination of the topological structure set up, each MMC is expert to or arranges to being attached thereto other MMC.If when certain MMC breaks down and exits, the MMC of the row or column in this topological structure can as its redundant module, the negative level that can be exported by full-bridge submodule, is reduced the overall direct voltage of full row or full row, thus realizes the stable control of balancing energy.Therefore, the structure of this DC transmission system by setting up MMC crossing redundancy structure, thus increases substantially system survivability, makes the safety and reliability of equipment be able to remarkable lifting.
The DC transmission system that the present invention sets up is that several MMC connect successively in a column direction.In the row direction, layering parallel connection is carried out with behavior arrangement in the same polarity direct current pole of each MMC unit, can improve direct voltage and the electric current of flexible direct current power transmission system, therefore, the present invention can significantly improve flexible direct current power transmission system capacity, realizes mass transport and the control of electric energy.
Have employed the form of full-bridge submodule and the mixing of half-bridge submodule in the present invention in MMC unit, realize passing through flexibly of ac high voltage and direct-current short circuit fault, operational percentage when improving system dc transient fault and robustness.
Accompanying drawing explanation
Fig. 1 is the DC transmission system structure chart of the modularization multi-level converter unit of the embodiment of the present invention;
Fig. 2 is the structure chart of the modularization multi-level converter unit of the embodiment of the present invention;
U1. ac bus, U2. converter transformer, U3. is soft opens loop, U4. brachium pontis reactor;
Fig. 3 is the half-bridge sub modular structure figure of the modularization multi-level converter unit of the embodiment of the present invention;
Fig. 4 is the full-bridge sub modular structure figure of the modularization multi-level converter unit of the embodiment of the present invention.
Embodiment
Below in conjunction with drawings and Examples, the present invention will be further described in detail.
A kind of DC transmission system based on modularization multi-level converter unit
(1) based on the structure of the DC transmission system of modularization multi-level converter unit
This DC transmission system is made up of M × N number of MMC and M+1 bar bus; Wherein, every N number of MMC forms an elementary layer, forms M elementary layer altogether; N number of MMC in each elementary layer is connected in parallel between a positive bus-bar and a negative busbar; M described elementary layer is connected successively, the negative busbar that the MMC that the positive bus-bar that namely in each elementary layer, each MMC connects is an elementary layer connects; The positive bus-bar that MMC in first module layer connects is provided with the positive pole of described DC transmission system, and the negative busbar that each MMC in last elementary layer connects is provided with the negative pole of described DC transmission system.
Wherein, MMC adopts asymmetric one pole Main connection form, wherein, the bridge arm structure of MMC adopts three-phase six bridge arm structure, each brachium pontis forms according to certain ratio cascade by half-bridge submodule and full-bridge submodule, described half-bridge submodule and full-bridge submodule as formed based on IGBT, are also in series with brachium pontis reactor in each brachium pontis by all-controlling power electronics device simultaneously.Current converter in MMC, can change mutually by the AC energy of the direct current energy of DC power transmission line and transmission line of alternation current, and MMC also includes converter transformer and softly opens loop.
(2) based on the operation principle of the DC transmission system of modularization multi-level converter unit
The similar matrix form of the DC transmission system that the present invention sets up, wherein any one MMC unit is expert to or is longitudinally all had other MMC unit be attached thereto.Therefore, each row has M MMC unit to connect successively, and realize the series boosting of DC transmission system, every a line has N number of MMC unit, carries out layering parallel connection with behavior arrangement, the parallel connection realizing DC transmission system is incremental.Therefore, whole DC transmission system significantly improves flexible direct current power transmission system capacity.
If a certain MMC unit of DC transmission system breaks down exit, the MMC of the row or column then in this topological structure can as redundant module, form crossing redundancy structure, by the negative level that full-bridge submodule exports, optionally can reduce the overall direct voltage of full row or full row, thus realize the stable control of balancing energy.
The form adopting full-bridge submodule to mix mutually with half-bridge submodule in MMC unit in the present invention, the negative level that full-bridge submodule exports realizes ac high voltage and passes through, rapid decay direct fault current, and provide lasting reactive power support to AC system, meet the demand that alternating current-direct current fault is passed through flexibly.
In the present embodiment, adopt the mixed type MMC unit of half-bridge submodule and full-bridge sub module cascade, as other execution modes, also can adopt the MMC unit that only comprises half-bridge submodule or only adopt the MMC unit comprising full-bridge submodule.
Under the thinking that the present invention provides; the mode easily expected to those skilled in the art is adopted to convert the technological means in above-described embodiment, replace, revise; and the effect played goal of the invention that is substantially identical with the relevant art means in the present invention, that realize is also substantially identical; the technical scheme of such formation is carried out fine setting to above-described embodiment and is formed, and this technical scheme still falls within the scope of protection of the present invention.
Claims (3)
1. based on a DC transmission system for modularization multi-level converter unit, it is characterized in that, this DC transmission system is made up of M × N number of MMC and M+1 bar bus; Wherein, every N number of MMC forms an elementary layer, forms M elementary layer altogether; N number of MMC in each elementary layer is connected in parallel between a positive bus-bar and a negative busbar; M described elementary layer is connected successively, the negative busbar that the MMC that the positive bus-bar that namely in each elementary layer, each MMC connects is an elementary layer connects; The positive bus-bar that MMC in first module layer connects is provided with the positive pole of described DC transmission system, and the negative busbar that each MMC in last elementary layer connects is provided with the negative pole of described DC transmission system.
2. a kind of DC transmission system based on modularization multi-level converter unit according to claim 1, it is characterized in that, described MMC is three-phase six bridge arm structure, each brachium pontis is made up of according to the ratio cascade of setting half-bridge submodule and full-bridge submodule, and each brachium pontis is also in series with brachium pontis reactor.
3. a kind of DC transmission system based on modularization multi-level converter unit according to claim 2, it is characterized in that, described MMC also comprises: converter transformer and softly open loop.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510657389.1A CN105281314A (en) | 2015-10-12 | 2015-10-12 | DC power transmission system based on modularized multi-level converter unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510657389.1A CN105281314A (en) | 2015-10-12 | 2015-10-12 | DC power transmission system based on modularized multi-level converter unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105281314A true CN105281314A (en) | 2016-01-27 |
Family
ID=55149864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510657389.1A Pending CN105281314A (en) | 2015-10-12 | 2015-10-12 | DC power transmission system based on modularized multi-level converter unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105281314A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106356880A (en) * | 2016-08-31 | 2017-01-25 | 国家电网公司 | MMC converting system and fault-tolerant control method thereof |
| CN109103915A (en) * | 2018-08-31 | 2018-12-28 | 国家电网有限公司 | Inverter Station topological structure and its control method suitable for the transformation of high-voltage large-capacity Traditional DC engineering receiving end |
| CN109830977A (en) * | 2019-04-08 | 2019-05-31 | 武汉大学 | The control method of direct current transportation circuit, DC transmission system and direct current transportation circuit |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996006477A1 (en) * | 1994-08-24 | 1996-02-29 | Asea Brown Boveri Ab | Converter connection with a balancing circuit |
| CN102611096A (en) * | 2012-03-13 | 2012-07-25 | 浙江大学 | Bipolar direct current power transmission system with direct current failure self-elimination capacity |
| CN102938560A (en) * | 2012-10-19 | 2013-02-20 | 浙江大学 | Direct-current converter station based on bipolar structure |
| CN204156529U (en) * | 2014-10-08 | 2015-02-11 | 中国南方电网有限责任公司电网技术研究中心 | Flexible direct current back-to-back system with redundant switching reactive compensation function |
| CN104967141A (en) * | 2015-06-26 | 2015-10-07 | 许继电气股份有限公司 | Hybrid direct current transmission system |
-
2015
- 2015-10-12 CN CN201510657389.1A patent/CN105281314A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996006477A1 (en) * | 1994-08-24 | 1996-02-29 | Asea Brown Boveri Ab | Converter connection with a balancing circuit |
| CN102611096A (en) * | 2012-03-13 | 2012-07-25 | 浙江大学 | Bipolar direct current power transmission system with direct current failure self-elimination capacity |
| CN102938560A (en) * | 2012-10-19 | 2013-02-20 | 浙江大学 | Direct-current converter station based on bipolar structure |
| CN204156529U (en) * | 2014-10-08 | 2015-02-11 | 中国南方电网有限责任公司电网技术研究中心 | Flexible direct current back-to-back system with redundant switching reactive compensation function |
| CN104967141A (en) * | 2015-06-26 | 2015-10-07 | 许继电气股份有限公司 | Hybrid direct current transmission system |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106356880A (en) * | 2016-08-31 | 2017-01-25 | 国家电网公司 | MMC converting system and fault-tolerant control method thereof |
| CN106356880B (en) * | 2016-08-31 | 2018-10-19 | 国家电网公司 | A kind of MMC commutation systems and its fault tolerant control method |
| CN109103915A (en) * | 2018-08-31 | 2018-12-28 | 国家电网有限公司 | Inverter Station topological structure and its control method suitable for the transformation of high-voltage large-capacity Traditional DC engineering receiving end |
| CN109830977A (en) * | 2019-04-08 | 2019-05-31 | 武汉大学 | The control method of direct current transportation circuit, DC transmission system and direct current transportation circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104795834B (en) | A kind of Hybrid HVDC topological structure and control method | |
| CN105324924B (en) | Mechanical bypass switch device, converter arm and power inverter | |
| CN105191093A (en) | Multilevel converter with hybrid full-bridge cells | |
| CN102593866A (en) | Unified power flow controller based on modular multilevel converter structure | |
| CN106356880B (en) | A kind of MMC commutation systems and its fault tolerant control method | |
| CN102983577A (en) | Convertible static compensator provided with modular multilevel converter structure | |
| CN102354969A (en) | Control device for flexible direct current (DC) transmission system of modular multilevel converter (MMC) | |
| CN213585162U (en) | AC/DC power supply structure of data center | |
| CN102969708A (en) | Interline power flow controller based on modular multi-level converter structure | |
| CN104993716A (en) | Modular multilevel converter and hybrid double-unit sub-module | |
| CN112886594A (en) | AC/DC power supply structure of data center | |
| CN104767393A (en) | Cascading-parallel connection mixing converter device | |
| CN105281314A (en) | DC power transmission system based on modularized multi-level converter unit | |
| CN211089207U (en) | Parallel charging module and double-mixed type direct current screen system applying same | |
| CN102904420A (en) | Multi-port current transformer | |
| CN100385782C (en) | Multiple-level serially connected high-voltage inverter | |
| CN106655850A (en) | Modular multilevel converter for eliminating low-frequency voltage fluctuation | |
| CN104037754A (en) | Modularized multi-level flexible DC (Direct Current) topology circuit applicable to fault ride-through | |
| CN202535087U (en) | Unified power flow controller based on modular multilevel converter structure | |
| CN103532395A (en) | Power supply circuit of power module of chain circuit SVG (static var generator) | |
| CN204578377U (en) | A kind of cascade-mixing transformation apparatus in parallel | |
| CN105429491A (en) | Inequality constraints-based auxiliary capacitor concentrated single clamping MMC self voltage-sharing topology | |
| CN105515427A (en) | Auxiliary-capacitor-free full-bridge MMC self-voltage-sharing topology based on inequality constraints | |
| CN105450070A (en) | Non-auxiliary-capacitance type half-bridge/full-bridge parallel-serial MMC self-voltage-sharing topology based on inequality constraints | |
| CN105471259A (en) | Auxiliary capacitor centralized half-bridge/single-clamping series-parallel MMC automatic voltage-equalizing topology based on equality constraint |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20160127 |