CN110429622A - It is a kind of for compensating the multi layer control system of laod unbalance - Google Patents
It is a kind of for compensating the multi layer control system of laod unbalance Download PDFInfo
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- CN110429622A CN110429622A CN201910777588.4A CN201910777588A CN110429622A CN 110429622 A CN110429622 A CN 110429622A CN 201910777588 A CN201910777588 A CN 201910777588A CN 110429622 A CN110429622 A CN 110429622A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/26—Arrangements for eliminating or reducing asymmetry in polyphase networks
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks
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Abstract
The present invention provides a kind of for compensating the multi layer control system of laod unbalance, it is characterized in that, including signal acquisition unit, multi layer control unit, execution unit, signal acquisition unit is the measuring unit of load-side, grid side, each phase voltage in compensation side and MMC compensator inside and electric current；Then multi layer control unit distributes first by the collected electric signal parameter coordinate transform of signal acquisition unit and is used as controlled device in the middle to each layer of control and constitutes feedback；Execution unit acts under the triggering of multi layer control unit, to realize the three-phase equilibrium on transmission line of electricity.The beneficial effects of the present invention are: multi layer control unit of the invention has the characteristics that the division of labor is clear, it is simple to realize, has excellent performance, in the Practical Project of the power grid three-phase imbalance caused by can be applied to by laod unbalance.Using the reactive power compensator based on half-bridge submodule MMC, can overcome the deficiencies in the prior art, there is apparent application advantage in the power transmission network of high-power.
Description
Technical field
The present invention relates to technical field of electric power more particularly to a kind of for compensating the multi layer control system of laod unbalance.
Background technique
With the development of economy, people's quality of life steps up, and power quality problem has become an emphasis and asks
Topic.The assessment of power quality includes power factor, harmonic content and three-phase voltage current degree of unbalancedness etc., causes electric energy matter
The reason of amount problem on the one hand include have non-linear, impact, wavy load it is grid-connected, cause in power grid in short-term
Between there is the problems such as three-phase load unbalance, power factor is too low.On the other hand, wind-powered electricity generation, photovoltaic power generation etc. newly can generation modes
Large-scale grid connection, can issue as main topology and can also draw in harmonic injection power grid using switching-type device in reversals
The problem of power generation network electric energy quality.Therefore the research improved currently for grid power quality has had very great meaning
Justice.
Three-phase imbalance is one of the important indicator for measuring power quality, and the three-phase imbalance of electric system refers to three-phase electricity
Pressure/current amplitude is not of uniform size and its difference has been more than defined range.Current China is for (Point at points of common connection
Of Common Coupling, abbreviation PCC) for imbalance of three-phase voltage regulation when power grid operates normally, negative sequence voltage is uneven
Degree is no more than 2%, must not exceed 4% in short-term.Three-phase imbalance will affect the normal operation of power equipment, and electricity can be threatened when serious
The safe operation of Force system.Laod unbalance is an important factor for influencing power grid three-phase imbalance, because of system threephase load one
Directly variable condition is in so three-phase load is often unbalanced, second is that because having large-scale load such as rolling mill, electric arc furnaces etc.
The pollution of large-scale out-of-balance load also results in the imbalance of three-phase voltage current on route, therefore studies and face laod unbalance
The specified value how fast and accurately to compensate voltage/current at PCC to three-phase equilibrium has positive meaning and important
Practical value.
Summary of the invention
The present invention provides a kind of for compensating the multi layer control system of laod unbalance, including signal acquisition unit, more
Layer control unit, execution unit,
Signal acquisition unit is the measurement of load-side, grid side, each phase voltage in compensation side and MMC compensator inside and electric current
Unit；
Then multi layer control unit first distributes the collected electric signal parameter coordinate transform of signal acquisition unit to every
It is used as controlled device in one layer of control and constitutes feedback；
Execution unit acts under the triggering of multi layer control unit, to realize the three-phase equilibrium on transmission line of electricity.
As a further improvement of the present invention, the multi layer control unit includes main power control module, submodule capacitor
Voltage balancing control module, uneven circulation suppression module,
Main power control module uses symmetrical component method, and each three-phase signal is become positive and negative zero sequence and is controlled respectively, simultaneously
Negative phase-sequence control section uses outer voltage control strategy；
The strategy that submodule capacitor voltage balances control module uses distributed AC servo system, is equipped in each submodule
Corresponding controllers；
Uneven circulation suppression module also extracts zero-sequence component using α β coordinate system transformation simultaneously and PR control pair is respectively adopted
It is controlled, can also inhibit other than the two frequency multiplication circulation of negative phase-sequence that can inhibit traditional by main power control in order to compensate for
Imbalance circulation in inside caused by unbalance voltage at PCC.
As a further improvement of the present invention, the execution unit is the reactive power compensator based on half-bridge submodule MMC.
As a further improvement of the present invention, the reactive power compensator includes half-bridge submodule MMC inverter, and described half
Bridge submodule MMC inverter compensates three-phase voltage current at PCC by main power control, using son while compensation
Module capacitance voltage balancing control strategy guarantees submodule capacitor voltage balance, by being α β coordinate system and zero sequence by Circulation Decomposition
Part is respectively adopted PR controller and carries out loop current suppression to it.
As a further improvement of the present invention, the half-bridge submodule MMC inverter includes MMC inverter, and the MMC is changed
Load side transmission line of electricity is accessed by transformers connected in parallel in the exchange side for flowing device.
As a further improvement of the present invention, the MMC inverter includes six bridge arms, and each bridge arm is by reactor and N
A submodule is sequentially connected in series.
The beneficial effects of the present invention are: multi layer control unit of the invention has, the division of labor is clear, it is simple to realize, has excellent performance
The characteristics of, in the Practical Project of the power grid three-phase imbalance caused by can be applied to by laod unbalance.The present invention is utilized and is based on
The reactive power compensator of half-bridge submodule MMC, can overcome the deficiencies in the prior art, have in the power transmission network of high-power
Apparent application advantage.
Detailed description of the invention
Fig. 1 is the principle of the present invention block diagram；
Structural representation when Fig. 2 is the reactive power compensator access transmission system of the invention based on half-bridge submodule MMC
Figure；
Fig. 3 is in the present invention for adjusting the novel multi-layer control block diagram of power grid three-phase imbalance；
Fig. 4 is the reactive power compensator topology diagram based on half-bridge submodule MMC in the present invention；
Fig. 5 is main power control module schematic diagram of the invention；
Fig. 6 is submodule capacitor voltage balance control module schematic diagram of the invention；
Fig. 7 is uneven circulation suppression module schematic diagram of the invention.
Specific embodiment
As shown in Figure 1, being directed to the regulation of load-side three-phase imbalance, it is uneven for compensating load that the invention discloses one kind
The multi layer control system of weighing apparatus, including signal acquisition unit, multi layer control unit, execution unit,
Wherein, signal acquisition unit is load-side, grid side, each phase voltage in compensation side and MMC compensator inside and electric current
Measuring unit；
Multi layer control unit is first by the collected electric signal parameter coordinate transform of signal acquisition unit, distribution to each layer
It is used as controlled device in control and constitutes feedback, multi layer control schematic diagram is as shown in Figure 4.It include main function in multi layer control unit
Rate control module, submodule capacitor voltage balance control module, uneven circulation suppression module.Multi layer control unit is according to transmission of electricity
Line voltage distribution, current signal and judging unit signal compensation control reactive power (injection/absorption), so as to improve at PCC three
Phase degree of unbalancedness.Main power control module uses symmetrical component method, and each three-phase signal is become positive and negative zero sequence and is controlled respectively, together
When negative phase-sequence control section have more novel outer voltage control strategy；Submodule capacitor voltage balances control module strategy and uses
Distributed AC servo system, is equipped with corresponding controllers in each submodule, can reduce pass to the data of central controller in this way
Throughput rate；Uneven circulation suppression module using α β coordinate system transformation simultaneously also extract zero-sequence component be respectively adopted PR control to its into
Row control, this method can also inhibit by main power control other than the two frequency multiplication circulation of negative phase-sequence that can inhibit traditional in order to mend
Imbalance circulation in inside caused by unbalance voltage at PCC is repaid, is reached and is reduced submodule capacitor voltage fluctuation, inhibits DC side
The advantages such as two double-frequency fluctuations.
It, should be based on half-bridge submodule MMC's using the reactive power compensator based on half-bridge submodule MMC as execution unit
Reactive power compensator includes half-bridge submodule MMC inverter, and half-bridge submodule MMC inverter accesses transmission line of electricity schematic diagram as schemed
Shown in 2, whereinFor sending end voltage,For sending end electric current,For voltage at PCC,For load side electric current,For MMC compensation
Device compensates electric current；Rs、LsFor net side line impedance；Rc、LcFor the connection impedance at compensator to PCC.
Half-bridge submodule MMC inverter includes: a MMC inverter, exchanges side by transformers connected in parallel and accesses load
Side transmission line of electricity, in detail topology are as shown in Figure 3, wherein Sn(n=1~2) are switching device (usually IGBT), Dn(n=1
It~2) is switching device anti-paralleled diode, CSMFor submodule capacitance, CZFor DC bus capacitor value, UcFor submodule voltage,
uSMFor submodule output voltage, iSMElectric current, L are exported for submodule0For bridge arm reactor inductance value, UdcIt is straight for MMC compensation device
Flow side voltage value, iujFor upper bridge arm current, iljFor lower bridge arm electric current (j=a, b, c).
The MMC inverter includes six bridge arms, and each bridge arm is sequentially connected in series by reactor and N number of submodule.
Half-bridge submodule MMC inverter compensates three-phase voltage current at PCC by main power control, in compensation
Submodule capacitor voltage balance is guaranteed using submodule capacitor voltage balance control strategy simultaneously, by being α β seat by Circulation Decomposition
Mark system and zero sequence part, which are respectively adopted PR controller and carry out loop current suppression to it, guarantees that internal circulation is smaller, reduces submodule electricity
The fluctuation range for holding voltage, eliminates DC side two double-frequency fluctuations as caused by zero sequence circulation.
The present invention proposes a kind of based on Modular multilevel converter (MMC) aiming at the problem that loading three-phase imbalance
Reactive power compensator constitute load three-phase imbalance regulator control system.The system can effectively administer power grid three-phase imbalance and ask
Topic.
Beneficial effects of the present invention are as follows:
1) present invention presses down using by main power control module, submodule capacitor voltage balance control module, uneven circulation
Multi layer control unit under the conditions of the imbalance of molding block composition can guarantee half-bridge submodule MMC compensator stable operation
While, three-phase imbalance at power grid PCC can be compensated rapidly, thus more economical reliable triggering compensation execution unit movement.
The control system has the characteristics that the division of labor is clear, it is simple to realize, has excellent performance, the electricity caused by can be applied to by laod unbalance
In the Practical Project of net three-phase imbalance.
2) present invention can overcome the prior art using a kind of novel reactive power compensator based on half-bridge submodule MMC
Deficiency, in the power transmission network of high-power have apparent application advantage, such as adjust accurately and rapidly；Output level quantity
More, harmonic content is few；Have two kinds of compensation abilitys of reactive compensation and imbalance compensation etc..
The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be said that
Specific implementation of the invention is only limited to these instructions.For those of ordinary skill in the art to which the present invention belongs, In
Under the premise of not departing from present inventive concept, a number of simple deductions or replacements can also be made, all shall be regarded as belonging to of the invention
Protection scope.
Claims (6)
1. a kind of for compensating the multi layer control system of laod unbalance, which is characterized in that including signal acquisition unit, multilayer control
Unit processed, execution unit,
Signal acquisition unit is the measurement list of load-side, grid side, each phase voltage in compensation side and MMC compensator inside and electric current
Member；
Then multi layer control unit first distributes the collected electric signal parameter coordinate transform of signal acquisition unit to each layer
It is used as controlled device in control and constitutes feedback；
Execution unit acts under the triggering of multi layer control unit, to realize the three-phase equilibrium on transmission line of electricity.
2. multi layer control system according to claim 1, it is characterised in that: the multi layer control unit includes main power control
Molding block, submodule capacitor voltage balance control module, uneven circulation suppression module,
Main power control module uses symmetrical component method, and each three-phase signal is become positive and negative zero sequence and is controlled respectively, while negative phase-sequence
Control section uses outer voltage control strategy；
The strategy that submodule capacitor voltage balances control module uses distributed AC servo system, is equipped in each submodule corresponding
Controller；
Uneven circulation suppression module using α β coordinate system transformation simultaneously also extract zero-sequence component be respectively adopted PR control to its into
Row control, can also inhibit by main power control other than the two frequency multiplication circulation of negative phase-sequence that can inhibit traditional in order to compensate for PCC
Locate inside imbalance circulation caused by unbalance voltage.
3. multi layer control system according to claim 1, it is characterised in that: the execution unit is based on half-bridge submodule
The reactive power compensator of MMC.
4. multi layer control system according to claim 3, it is characterised in that: the reactive power compensator includes half-bridge submodule
Block MMC inverter, the half-bridge submodule MMC inverter compensate three-phase voltage current at PCC by main power control,
Submodule capacitor voltage balance is guaranteed using submodule capacitor voltage balance control strategy while compensating, by dividing circulation
Solution is that α β coordinate system and zero sequence part are respectively adopted PR controller and carry out loop current suppression to it.
5. multi layer control system according to claim 4, it is characterised in that: the half-bridge submodule MMC inverter includes
Load side transmission line of electricity is accessed by transformers connected in parallel in the exchange side of MMC inverter, the MMC inverter.
6. multi layer control system according to claim 5, it is characterised in that: the MMC inverter includes six bridge arms, often
A bridge arm is sequentially connected in series by reactor and N number of submodule.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160139578A1 (en) * | 2013-06-12 | 2016-05-19 | Abb Technology Ltd | Methods and devices for controlling active power flow in a three-phase modular multilevel converter |
| CN108808710A (en) * | 2018-06-25 | 2018-11-13 | 国网上海市电力公司 | A kind of UPFC three-phase imbalance optimization methods based on nonlinear Control |
| CN108832642A (en) * | 2018-06-29 | 2018-11-16 | 广东电网有限责任公司 | A kind of regulator control system and judgment method for transmission line of electricity three-phase imbalance |
| CN109888784A (en) * | 2018-12-29 | 2019-06-14 | 上海电力学院 | A kind of passive control method based on MMC-SAPF under the conditions of unbalanced source voltage |
-
2019
- 2019-08-22 CN CN201910777588.4A patent/CN110429622A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20160139578A1 (en) * | 2013-06-12 | 2016-05-19 | Abb Technology Ltd | Methods and devices for controlling active power flow in a three-phase modular multilevel converter |
| CN108808710A (en) * | 2018-06-25 | 2018-11-13 | 国网上海市电力公司 | A kind of UPFC three-phase imbalance optimization methods based on nonlinear Control |
| CN108832642A (en) * | 2018-06-29 | 2018-11-16 | 广东电网有限责任公司 | A kind of regulator control system and judgment method for transmission line of electricity three-phase imbalance |
| CN109888784A (en) * | 2018-12-29 | 2019-06-14 | 上海电力学院 | A kind of passive control method based on MMC-SAPF under the conditions of unbalanced source voltage |
Non-Patent Citations (3)
| Title |
|---|
| 宋平岗 等: "不平衡电网电压下MMC的比例降阶谐振控制策略", 《电测与仪表》 * |
| 张铭: "负载不平衡条件下STATCOM控制技术研究", 《中国优秀硕士学位论文全文数据库》 * |
| 赵昕 等: "采用载波移相技术的模块化多电平换流器", 《中国电机工程学报》 * |
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