CN103066567A - Hierarchical sectional capacity balance control method based on switching number - Google Patents
Hierarchical sectional capacity balance control method based on switching number Download PDFInfo
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- CN103066567A CN103066567A CN2012105339959A CN201210533995A CN103066567A CN 103066567 A CN103066567 A CN 103066567A CN 2012105339959 A CN2012105339959 A CN 2012105339959A CN 201210533995 A CN201210533995 A CN 201210533995A CN 103066567 A CN103066567 A CN 103066567A
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- brachium pontis
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/4835—Converters with outputs that each can have more than two voltages levels comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
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Abstract
The invention provides a hierarchical sectional capacity balance control method based on switching number. The switching number of sub-modules is used as allocating objects so that flexibility of strategy operation is ensured, enormous information processing is enabled to be completed very simply, conveniently and fast, and reliability and processing speed of a system are improved. Different sub-modules are confirmed according to judgment data such as voltage feedback and current directions of all subsections so that on the premise of enabling the system to operate normally, sub-module capacitor voltage balance is realized, and stable and reliable operation of the whole bridge arm sub-module in a converter and synergy coordination of the whole bridge arm sub-module with a converter protection system are ensured.
Description
Technical field
The invention belongs to electric and electronic technical field, be specifically related to a kind of layer and section formula capacitive balance control method based on the switching number.
Background technology
Different from traditional high voltage dc transmission technology, the flexible DC power transmission converter is flexible with its control, trend control is easy to upset, can conveniently realize reactive power support and the advantages such as FREQUENCY CONTROL, the black startup of realization, becomes gradually the direct current transportation field development trend in future; Wherein, be rapidly developed based on the flexible DC power transmission engineering of modularization multi-level converter for topology.Based on MMC(Module Multilevel Convertor) the converter submodule capacitance voltage balanced algorithm of mode is the core algorithm of realizing the operation of converter valve voltage stabilization; But in large capacity, high voltage MMC flexible DC power transmission field, along with increasing of submodule number, the control of capacitance voltage balance becomes increasingly complex.In the present disclosed data of home and overseas, relevant for the data about capacitance voltage control plan algorithm message semantic definition, be that the large capacity of distribution object, data and the patent of high voltage MMC current transformer submodule capacitance voltage balancing control algorithm lack especially based on submodule switching number especially seldom.
Summary of the invention
In order to overcome above-mentioned the deficiencies in the prior art, the invention provides a kind of layer and section formula capacitive balance control method based on the switching number, take submodule switching number as distribution object, guaranteed the flexibility of tactful operation, make huge information processing obtain very convenient simple and direct mode and finish, improved system reliability and processing speed; By to bases for estimation such as each segmentation Voltage Feedback, the senses of current, determine different switching submodules, system can be guaranteed under the stable operation prerequisite, realize submodule capacitance voltage balance; Guarantee whole brachium pontis submodule in converter reliable and stable operation and with the coordinated of converter unit protection system.
In order to realize the foregoing invention purpose, the present invention takes following technical scheme:
A kind of layer and section formula capacitive balance control method based on the switching number is provided, said method comprising the steps of:
Step 1: gather and gather the submodule work state information;
Step 2: the voltage of submodule is sorted;
Step 3: the submodule number of determining and issue each brachium pontis input;
Step 4: calculate the submodule number M that brachium pontis needs switching;
Step 5: select the switching submodule.
In the described step 1, brachium pontis segmentation control unit is transferred to brachium pontis with the submodule work state information that gathers and gathers control unit and carry out gathering of submodule work state information.
Described submodule work state information comprises capacitance voltage and fault message.
In the described step 2, brachium pontis gathers control unit the voltage of submodule is sorted according to from big to small principle.
In the described step 3, the circulation control unit is controlled the voltage signal that protection system passes down with the utmost point and is nursed one's health into the number of levels that each brachium pontis produces, i.e. the submodule number that drops into of each brachium pontis, and this submodule information of number is issued to brachium pontis gathers control unit.
In the described step 4, brachium pontis gathers the number of levels that number of levels that control unit dropped into according to this brachium pontis and needs drop into, and adopts minimum approximatioss to calculate the submodule number M that brachium pontis needs switching.
In the described step 5, select the switching submodule according to the brachium pontis sense of current and module capacitance voltage ranking results, wherein:
Flow to negative busbar as positive direction take positive bus-bar, if the sense of current is selected the less M of capacitance voltage in the brachium pontis for just at this moment
1Individual module drops into;
Flow to positive bus-bar as negative direction take negative busbar, if this moment, the sense of current was negative, select the larger M of capacitance voltage in the brachium pontis
2Individual module drops into.
Described brachium pontis segmentation control unit, brachium pontis gather the valve base control appliance that control unit, light CT merging and interface unit, circulation control unit and MMC valve monitoring unit have formed modularization multi-level converter control protection system.
Compared with prior art, beneficial effect of the present invention is:
1. take submodule switching number as distribution object, guarantee the flexibility of tactful operation, made huge information processing obtain very convenient simple and direct mode and finish, improved system reliability and processing speed;
2. by to bases for estimation such as each segmentation Voltage Feedback, the senses of current, determine different switching submodules, system can be guaranteed under the stable operation prerequisite, realize submodule capacitance voltage balance;
3. guarantee whole brachium pontis submodule in converter reliable and stable operation and with the coordinated of converter unit protection system;
4. the valve base controller has adopted the thinking of layer and section control the brachium pontis controller to be divided into brachium pontis gathers control unit and brachium pontis segmentation control unit is two-layer, has solved large capacity MMC flexible DC power transmission current transformer and can't adopt single control unit to finish the difficult problem of brachium pontis control;
5. brachium pontis gathers control unit and is responsible for this brachium pontis and divides intersegmental capacitance voltage balance, and brachium pontis segmentation control unit is responsible for the submodule capacitance voltage balance in this segmentation, thereby has guaranteed the balance of voltage of whole brachium pontis;
6. brachium pontis gathers control unit by communicating by letter with each brachium pontis segmentation control unit in this brachium pontis, all submodule information is gathered, and the antithetical phrase module voltage sorts, and is used for each submodule switching, thereby can realizes the input of voltage height module when switching and cut out control.
Description of drawings
Fig. 1 is capacitive balance control structure figure in the modularization multi-level converter.
Fig. 2 is based on the layer and section formula capacitive balance control structure figure of switching number in the embodiment of the invention.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail.
At modularization multi-level converter (Module Multilevel Convertor, be called for short the MMC converter), especially in the large capacity converter, submodule quantity is huge, in control procedure, need to guarantee that the submodule voltage in each brachium pontis remains in the scope of a relative equilibrium, the many factors that this balance that relates to submodule capacitance voltage in the brachium pontis need to be considered.For the greatly large capacity MMC converter of module number, level number is more, and control cycle is shorter in real time, the more difficult realization of capacitance voltage balance control; Simultaneously, limit by valve base control unit interface quantity, the valve base control appliance need to be adopted the realization of layer and section processing mode to the independent control of each submodule.Temporary location as the valve base control appliance---brachium pontis gathers control unit, is that the submodule information with the whole brachium pontis of a plurality of brachium pontis segmenting units gathers, puts in order, gathers the temporary location that the bridge arm voltage equilibrium strategy is processed and brachium pontis Global Macros strategy is implemented.
The brachium pontis that the present invention is directed to the valve base control appliance gathers control unit and has designed a kind of layer and section formula module capacitance balance of voltage control method take submodule switching number as target, guarantee whole brachium pontis submodule in converter reliable and stable operation and with the coordinated of converter unit protection system.
Modularization multi-level converter by 3 mutually totally 6 brachium pontis form, the submodule capacitance voltage balancing control algorithm that the present invention relates to be based on MMC converter valve base controller shown in Figure 1, this valve base controller gathers control unit by 1 central valve base controller, 6 brachium pontis and some brachium pontis segmentation control units form.Each brachium pontis gathers control unit by 1 brachium pontis that overlaps and several brachium pontis segmentation control units form, its bridge arm segmentation control unit is finished the balance of voltage control of the submodule of this brachium pontis segmentation, and brachium pontis gathers control unit and finishes the intersegmental balance of voltage control of each minute of this brachium pontis; 6 brachium pontis gather control unit and connect a central valve base controller, and this central valve base controller main frame is responsible for finishing 6 balance of voltage controls between brachium pontis.
Such as Fig. 2, MMC converter submodule capacitance voltage balance control method provided by the invention, concrete grammar is as follows:
1, brachium pontis segmentation control unit with the submodule work state information that connects accept with arrangement after, the brachium pontis that is aggregated into this brachium pontis gathers control unit;
2, brachium pontis gather control unit then with in this brachium pontis all the voltage of submodules according to sorting from big to small;
3, the brachium pontis current control unit is controlled the voltage signal that protection system PCP passes down with the utmost point and is nursed one's health into the number of levels that each brachium pontis produces, i.e. the submodule number that drops into of each brachium pontis; And this information is issued to each brachium pontis gathers control unit;
4, brachium pontis gathers the number of levels that number of levels that control unit dropped into according to this brachium pontis and needs drop into, and calculates the submodule number M that this brachium pontis in this modulation needs switching;
5, when this moment this brachium pontis sense of current for just (flowing to negative busbar for just by positive bus-bar), with the less M of capacitance voltage in this brachium pontis
1Individual module drops into; When this moment the sense of current for negative, the valve base controller is counted M, the M that voltage is larger according to the submodule that drops into
2Individual module drops into; By above way, make each brachium pontis submodule capacitance voltage of MMC current transformer keep balance.
Described brachium pontis segmentation control unit, brachium pontis gather the valve base control appliance VBC (Valve BaseController) that control unit, light CT merging and interface unit, circulation control unit and MMC valve monitoring unit have formed modularization multi-level converter control protection system.
Should be noted that at last: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although with reference to above-described embodiment the present invention is had been described in detail, those of ordinary skill in the field are to be understood that: still can make amendment or be equal to replacement the specific embodiment of the present invention, and do not break away from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (8)
1. layer and section formula capacitive balance control method based on the switching number is characterized in that: said method comprising the steps of:
Step 1: gather and gather the submodule work state information;
Step 2: the voltage of submodule is sorted;
Step 3: the submodule number of determining and issue each brachium pontis input;
Step 4: calculate the submodule number M that brachium pontis needs switching;
Step 5: select the switching submodule.
2. the layer and section formula capacitive balance control method based on the switching number according to claim 1, it is characterized in that: in the described step 1, brachium pontis segmentation control unit is transferred to brachium pontis with the submodule work state information that gathers and gathers control unit and carry out gathering of submodule work state information.
3. the layer and section formula capacitive balance control method based on the switching number according to claim 2, it is characterized in that: described submodule work state information comprises capacitance voltage and fault message.
4. the layer and section formula capacitive balance control method based on the switching number according to claim 1 is characterized in that: in the described step 2, brachium pontis gathers control unit the voltage of submodule is sorted according to from big to small principle.
5. the layer and section formula capacitive balance control method based on the switching number according to claim 1; it is characterized in that: in the described step 3; the circulation control unit is controlled the voltage signal that protection system passes down with the utmost point and is nursed one's health into the number of levels that each brachium pontis produces; be the submodule number that each brachium pontis drops into, and this submodule information of number is issued to brachium pontis gathers control unit.
6. the layer and section formula capacitive balance control method based on the switching number according to claim 1, it is characterized in that: in the described step 4, brachium pontis gathers the number of levels that number of levels that control unit dropped into according to this brachium pontis and needs drop into, and adopts minimum approximatioss to calculate the submodule number M that brachium pontis needs switching.
7. the layer and section formula capacitive balance control method based on the switching number according to claim 1 is characterized in that: in the described step 5, select the switching submodule according to the brachium pontis sense of current and module capacitance voltage ranking results, wherein:
Flow to negative busbar as positive direction take positive bus-bar, if the sense of current is selected the less M of capacitance voltage in the brachium pontis for just at this moment
1Individual module drops into;
Flow to positive bus-bar as negative direction take negative busbar, if this moment, the sense of current was negative, select the larger M of capacitance voltage in the brachium pontis
2Individual module drops into.
8. the layer and section formula capacitive balance control method based on the switching number according to claim 6 is characterized in that: described brachium pontis segmentation control unit, brachium pontis gather the valve base control appliance that control unit, light CT merging and interface unit, circulation control unit and MMC valve monitoring unit have formed modularization multi-level converter control protection system.
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| CN103368197A (en) * | 2013-07-15 | 2013-10-23 | 国网智能电网研究院 | Valve base control device and method of modularization multi-level converter |
| CN104767178A (en) * | 2015-04-16 | 2015-07-08 | 北京荣信慧科科技有限公司 | Protection and control system and control method based on bridge arm unit |
| CN105024574A (en) * | 2015-07-22 | 2015-11-04 | 上海交通大学 | MMC slave module capacitance voltage balance control method suitable for carrier phase shifting modulation |
| CN106483841A (en) * | 2015-08-26 | 2017-03-08 | 国网智能电网研究院 | A kind of field adjustable and the method for test circulation suppression strategy parameter |
| CN109728740A (en) * | 2019-01-22 | 2019-05-07 | 哈尔滨工业大学 | Modularization multi-level converter circulation inhibition method based on decoupling principle |
| CN112072933A (en) * | 2020-08-06 | 2020-12-11 | 清华大学 | Voltage balance control method of unidirectional current type modular multilevel converter |
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Cited By (13)
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| EP3024109A4 (en) * | 2013-07-15 | 2017-05-03 | State Grid Corporation of China (SGCC) | Valve base control device and method for modular multi-level convertor |
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| CN104767178A (en) * | 2015-04-16 | 2015-07-08 | 北京荣信慧科科技有限公司 | Protection and control system and control method based on bridge arm unit |
| CN104767178B (en) * | 2015-04-16 | 2018-01-09 | 北京荣信慧科科技有限公司 | The protection control method of Protection control system based on bridge arm unit |
| CN105024574A (en) * | 2015-07-22 | 2015-11-04 | 上海交通大学 | MMC slave module capacitance voltage balance control method suitable for carrier phase shifting modulation |
| CN105024574B (en) * | 2015-07-22 | 2017-09-08 | 上海交通大学 | The MMC submodule capacitor voltage balance control methods modulated suitable for phase-shifting carrier wave |
| CN106483841A (en) * | 2015-08-26 | 2017-03-08 | 国网智能电网研究院 | A kind of field adjustable and the method for test circulation suppression strategy parameter |
| CN106483841B (en) * | 2015-08-26 | 2019-08-30 | 国网智能电网研究院 | A kind of field adjustable and the method for testing loop current suppression policing parameter |
| CN109728740A (en) * | 2019-01-22 | 2019-05-07 | 哈尔滨工业大学 | Modularization multi-level converter circulation inhibition method based on decoupling principle |
| CN112072933A (en) * | 2020-08-06 | 2020-12-11 | 清华大学 | Voltage balance control method of unidirectional current type modular multilevel converter |
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Address after: 102209 Beijing City, Changping District science and Technology Park in the future smart grid research institute hospital Co-patentee after: CHINA-EPRI ELECTRIC POWER ENGINEERING Co.,Ltd. Patentee after: GLOBAL ENERGY INTERCONNECTION Research Institute Co-patentee after: DALIAN POWER SUPPLY COMPANY, STATE GRID LIAONING ELECTRIC POWER Co.,Ltd. Co-patentee after: State Grid Corporation of China Address before: 102211 Beijing city Changping District Xiaotangshan town big East Village Road No. 270 (future technology city) Co-patentee before: CHINA-EPRI ELECTRIC POWER ENGINEERING Co.,Ltd. Patentee before: STATE GRID SMART GRID Research Institute Co-patentee before: DALIAN POWER SUPPLY COMPANY OF LIAONING ELECTRIC POWER Co.,Ltd. Co-patentee before: State Grid Corporation of China |
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Effective date of registration: 20170531 Address after: 102209 Beijing City, Changping District science and Technology Park in the future smart grid research institute hospital Co-patentee after: DALIAN POWER SUPPLY COMPANY, STATE GRID LIAONING ELECTRIC POWER Co.,Ltd. Patentee after: GLOBAL ENERGY INTERCONNECTION Research Institute Co-patentee after: State Grid Corporation of China Address before: 102209 Beijing City, Changping District science and Technology Park in the future smart grid research institute hospital Co-patentee before: CHINA-EPRI ELECTRIC POWER ENGINEERING Co.,Ltd. Patentee before: GLOBAL ENERGY INTERCONNECTION RESEARCH INSTITUTE Co-patentee before: DALIAN POWER SUPPLY COMPANY, STATE GRID LIAONING ELECTRIC POWER Co.,Ltd. Co-patentee before: State Grid Corporation of China |