CN103066599A - Three-phase three-wire system mixed type integrated power system electric energy quality regulator - Google Patents
Three-phase three-wire system mixed type integrated power system electric energy quality regulator Download PDFInfo
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- CN103066599A CN103066599A CN2012105414540A CN201210541454A CN103066599A CN 103066599 A CN103066599 A CN 103066599A CN 2012105414540 A CN2012105414540 A CN 2012105414540A CN 201210541454 A CN201210541454 A CN 201210541454A CN 103066599 A CN103066599 A CN 103066599A
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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
- Y02E40/30—Reactive power compensation
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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
- Y02E40/40—Arrangements for reducing harmonics
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Abstract
The invention relates to a three-phase three-wire system mixed type integrated power system electric energy quality regulator, and belongs to the technical field of electric automation equipment. The three-phase three-wire system mixed type integrated power system electric energy quality regulator comprises a series compensation module and a parallel compensation module, wherein the series compensation module is connected with a power system, the parallel compensation module is connected with power system loads, and the series compensation module and the parallel compensation module are connected through a direct current bus. According to the electric energy quality regulator, a filter capacitor is added in the parallel compensation module, a three-phase converter in the parallel compensation module is enabled to only provide harmonic voltages, volume of the three-phase converter is lowered, device cost can be saved and work efficiency can be improved; the regulator can be used in a medium-voltage environment without a coupling transformer; the filter capacitor is added in the parallel compensation module, harmonic waves are compensated to the power system, and a certain reactive current can be provided for the loads at the same time; and compensation effect is good, cost performance is high, and application range is wide.
Description
Technical field
The present invention relates to a kind of three-phase three-wire system mixed type integrated power system electric energy regulator, belong to the electric automatization equipment technical field.
Background technology
The extensive application of various power electronic equipments has improved the utilance of electric energy to a great extent in the present electrical network, but the thing followed is: the harmonic wave that these power electronic equipments cause and reactive current produce serious pollution to electrical network, affect the quality of power supply of electrical network.Along with day by day popularizing and development of power electronic equipment, the harmonic wave in the electrical network and the harm that causes are day by day serious, have caused the generally attention of countries in the world.
Active Power Filter-APF (Active Power Filter is hereinafter to be referred as APF) is widely used just gradually because it has good harmonic compensation effect.APF can be divided into tandem type, parallel connection type two classes according to the difference of system configuration.Dissimilar APF is not quite similar to the compensation characteristic of same harmonic source.Now the existing parallel connection type APF that studies confirm that is fit to the rectification circuit of compensating direct current side inductor filter, i.e. current mode harmonic source; Tandem type APF is fit to the rectification circuit of compensating direct current lateral capacitance filtering, i.e. voltage-type harmonic source.More or less all have this situation of certain limitation for two kinds of Active Power Filter-APFs, the connection in series-parallel Active Power Filter-APF occurred.It combines parallel connection type active electric filter and series connection type active electric power filter, can the offset current harmonic wave, and also can the bucking voltage harmonic wave.If control properly, this structure can also effective compensation mains by harmonics voltage and power network fluctuation, and the power supply quality of load-side is significantly improved.Because therefore its feature richness is called as Research on Unified Power Quality Conditioner (Unified Power Quality Controller is hereinafter to be referred as UPQC), Figure 1 shows that the circuit theory diagrams of existing three-phase three-wire type uniform electric energy regulator.
In recent years, though there are a large amount of scholars to be engaged in the research of UPQC, and obtained remarkable result, current UPQC still has problems in following several respects:
1, part in parallel all adopts current transformer series connection outputting inductance structure basically, and this structure is only applicable to the junior situation of line voltage.If operation must increase coupling transformer under the mesohigh environment, this means that cost, volume improve significantly.No matter so that system from economically or performance consider, cost performance is all had a greatly reduced quality.
2, adopt structure mentioned above, if part in parallel wants to reach preferably compensation effect, need higher busbar voltage, mean that the voltage withstand class of IGBT and capacity sharply increase.
Summary of the invention
The objective of the invention is to propose a kind of three-phase three-wire system mixed type integrated power system electric energy regulator, change the structure of existing electric energy regulator, make the active filter of part in parallel connect and then be incorporated into the power networks with a passive filter first, can save like this capacity that coupling transformer in the traditional structure has also reduced current transformer and dc bus simultaneously.
The three-phase three-wire system mixed type integrated power system electric energy regulator that the present invention proposes, comprise series compensation module and shunt compensation module, described series compensation module links to each other with electrical network, described shunt compensation module links to each other with the electrical network load, and the series compensation module links to each other by dc bus with the shunt compensation module;
Described series compensation module comprises a 3-phase power converter, a three-phase transformer, three filter reactors, three filter capacitor branch roads and three groups of anti-parallel thyristors; The dc terminal of described 3-phase power converter is in parallel with dc bus, the interchange end of 3-phase power converter links to each other with an end of described three filter reactors respectively, the other end of three filter reactors links to each other with the input on the former limit of described three-phase transformer respectively, the output on the former limit of three-phase transformer interconnects, the input access electrical network of three-phase transformer secondary, the output of three-phase transformer secondary connects load; Described three filter capacitor branch roads are made of a filtering capacitor respectively, and an end of three filter capacitor branch roads links to each other with the transformer primary side input respectively, and the other end of three filter capacitor branch roads connects together; Described three groups of anti-parallel thyristors are in parallel with input and the output of described three-phase transformer secondary respectively;
Described shunt compensation module comprises a 3-phase power converter, three filter reactors, three filtering capacitors, a three-phase contactor and two groups of anti-parallel thyristors; One end of three groups of normally opened contacts of described three-phase contactor links to each other with the end that exchanges of 3-phase power converter respectively, the other end of three groups of normally opened contacts of three-phase contactor is connected respectively to an end of described three filter reactors, the other end of three filter reactors is connected respectively to an end of three filtering capacitors, this end of any two filter reactors in three filter reactors links to each other with an end of described two groups of anti-parallel thyristors respectively simultaneously, this end of another filter reactor in three filter reactors is drawn with drawing wire, the other end of three filtering capacitors links to each other with load as the output of shunt compensation module, after the other end of two groups of anti-parallel thyristors interconnects with draw wire and link to each other.
The three-phase three-wire system mixed type integrated power system electric energy regulator that the present invention proposes, its advantage is:
1, electric energy regulator of the present invention, owing in the shunt compensation module, having added filter capacitor, make the 3-phase power converter in the compensating module only need provide harmonic voltage, greatly reduce the capacity of 3-phase power converter, be conducive to save equipment cost, increase work efficiency; And need not coupling transformer, can in middle pressure ring border, put into operation.
2, electric energy regulator of the present invention owing to having added filter capacitor in the shunt compensation module, in to the power network compensation harmonic wave, also can be load certain reactive current is provided.
3, electric energy regulator of the present invention can be realized filtering control, compares with existing UPQC, no matter be for the voltage-source type load or the current source type load all has better harmonic compensation effect.
4. Research on Unified Power Quality Conditioner provided by the invention has all functions of traditional Research on Unified Power Quality Conditioner, and compensation effect is better, cost performance is higher, range of application is wider.
Description of drawings
Fig. 1 is the circuit theory diagrams of existing Research on Unified Power Quality Conditioner.
Fig. 2 is the circuit theory diagrams of the integrated power system electric energy regulator that proposes of the present invention.
Fig. 3 utilizes electric energy regulator of the present invention that power network current waveform behind the harmonic compensation is carried out in the current source type load.
Fig. 4 utilizes electric energy regulator of the present invention that power network current waveform behind the harmonic compensation is carried out in the voltage-source type load.
Fig. 5 is the load voltage waveform of utilizing after electric energy regulator of the present invention compensates the line voltage depression.
Fig. 6 is the load voltage waveform of utilizing after electric energy regulator of the present invention compensates mains by harmonics voltage.
Embodiment
The three-phase three-wire system mixed type integrated power system electric energy regulator that the present invention proposes, its circuit theory diagrams as shown in Figure 2, comprise series compensation module and shunt compensation module, described series compensation module links to each other with electrical network, described shunt compensation module links to each other with the electrical network load, and the series compensation module links to each other by dc bus with the shunt compensation module.
Above-mentioned series compensation module comprises a 3-phase power converter 1, a three-phase transformer 2, three filter reactor L
F1a/ L
F1b/ L
F1c, three filter capacitor branch road C
F1a/ C
F1b/ C
F1cWith three groups of anti-parallel thyristor S
1a/ S
1b/ S
1cThe dc terminal of 3-phase power converter 1 and dc bus C
DcParallel connection, the interchange end of 3-phase power converter 1 respectively with described three filter reactor L
F1a/ L
F1b/ L
F1cAn end link to each other three filter reactor L
F1a/ L
F1b/ L
F1cThe other end respectively with the input T on described three-phase transformer 2 former limits
A+/ T
B+/ T
C+Link to each other the output T on the former limit of three-phase transformer
A-/T
B-/T
C-interconnect the input Ta of three-phase transformer 2 secondary
+/ T
B+/ T
C+The access electrical network, the output T of three-phase transformer 2 secondary
A-/ T
B-/ T
C-Connect load; Described three filter capacitor branch road C
F1a/ C
F1b/ C
F1cConsisted of respectively three filter capacitor branch road C by a filtering capacitor
F1a/ C
F1b/ C
F1cAn end respectively with transformer 2 former limit input T
A+/ T
B+/ T
C+Link to each other three filter capacitor branch road C
F1a/ C
F1b/ C
F1cThe other end connect together; Described three groups of anti-parallel thyristor S
1a/ S
1b/ S
1cRespectively with the input T of described three-phase transformer 2 secondary
A+/ T
B+/ T
C+With output T
A-/ T
B-/ T
C-Be in parallel;
Described shunt compensation module comprises a 3-phase power converter 3, three filter reactor L
F2a/ L
F2b/ L
F2c, three filtering capacitor C
F2a/ C
F2b/ C
F2c, three-phase contactor K and two groups of anti-parallel thyristor S
2a/ S
2cThree groups of normally opened contact K of described three-phase contactor K
a/ K
b/ K
cAn end link to each other three groups of normally opened contact K of three-phase contactor K with the end that exchanges of 3-phase power converter 3 respectively
a/ K
b/ K
cThe other end be connected respectively to described three filter reactor L
F2a/ L
F2b/ L
F2cAn end, three filter reactor L
F2a/ L
F2b/ L
F2cThe other end be connected respectively to three filtering capacitor C
F2a/ C
F2b/ C
F2cAn end, L in three filter reactors
F2a/ L
F2b/ L
F2cAny two filter reactors this end simultaneously respectively with described two groups of anti-parallel thyristor S
2a/ S
2cAn end link to each other three filter reactor L
F2a/ L
F2b/ L
F2cIn this end of another filter reactor draw three filtering capacitor C with drawing wire
F2a/ C
F2b/ C
F2cThe other end link to each other two groups of anti-parallel thyristor S with load as the output of shunt compensation module
2a/ S
2cThe other end interconnect after with draw wire and link to each other.
Oscillogram when Fig. 3-Fig. 6 has provided the Research on Unified Power Quality Conditioner work of adopting the present invention's proposition.At this, load is not control rectifier strip resistance, Capacitance parallel connection load of control rectifier strip resistance load or three-phase of three-phase.
Electrical network, load parameter during work are as shown in the table:
Table 1 system parameters
But three-phase not control rectifier strip resistance load Approximate Equivalent is the current source type load, the current waveform after the Research on Unified Power Quality Conditioner that Fig. 3 proposes for employing the present invention compensates, and wherein upper figure is load current waveform, figure below is the power network current waveform.As can be seen from the figure, after 0.3 second series compensation module and shunt compensation module all put into operation, power network current had obtained obvious improvement.
But three-phase not control rectifier strip resistance, Capacitance parallel connection load Approximate Equivalent is the voltage-source type load.Current waveform after the Research on Unified Power Quality Conditioner that Fig. 4 proposes for employing the present invention compensates, wherein upper figure is load current waveform, figure below is the power network current waveform.As can be seen from the figure, this Research on Unified Power Quality Conditioner also has good compensation effect to capacitive load.
The compensation effect that Fig. 5 caves in to electrical network for the Research on Unified Power Quality Conditioner that adopts the present invention's proposition, depression occurs in 0.4 second.Falling the degree of depth is 10% of line voltage.The load of this moment is not control rectifier strip resistance, Capacitance parallel connection load of three-phase.
Fig. 6 adopts the Research on Unified Power Quality Conditioner of the present invention's proposition to the compensation effect of mains by harmonics.
Claims (1)
1. three-phase three-wire system mixed type integrated power system electric energy regulator, it is characterized in that this electric energy regulator comprises series compensation module and shunt compensation module, described series compensation module links to each other with electrical network, described shunt compensation module links to each other with the electrical network load, and the series compensation module links to each other by dc bus with the shunt compensation module;
Described series compensation module comprises a 3-phase power converter, a three-phase transformer, three filter reactors, three filter capacitor branch roads and three groups of anti-parallel thyristors; The dc terminal of described 3-phase power converter is in parallel with dc bus, the interchange end of 3-phase power converter links to each other with an end of described three filter reactors respectively, the other end of three filter reactors links to each other with the input on the former limit of described three-phase transformer respectively, the output on the former limit of three-phase transformer interconnects, the input access electrical network of three-phase transformer secondary, the output of three-phase transformer secondary connects load; Described three filter capacitor branch roads are made of a filtering capacitor respectively, and an end of three filter capacitor branch roads links to each other with the transformer primary side input respectively, and the other end of three filter capacitor branch roads connects together; Described three groups of anti-parallel thyristors are in parallel with input and the output of described three-phase transformer secondary respectively;
Described shunt compensation module comprises a 3-phase power converter, three filter reactors, three filtering capacitors, a three-phase contactor and two groups of anti-parallel thyristors; One end of three groups of normally opened contacts of described three-phase contactor links to each other with the end that exchanges of 3-phase power converter respectively, the other end of three groups of normally opened contacts of three-phase contactor is connected respectively to an end of described three filter reactors, the other end of three filter reactors is connected respectively to an end of three filtering capacitors, this end of any two filter reactors in three filter reactors links to each other with an end of described two groups of anti-parallel thyristors respectively simultaneously, this end of another filter reactor in three filter reactors is drawn with drawing wire, the other end of three filtering capacitors links to each other with load as the output of shunt compensation module, after the other end of two groups of anti-parallel thyristors interconnects with draw wire and link to each other.
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Cited By (10)
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| CN103618310A (en) * | 2013-12-05 | 2014-03-05 | 国家电网公司 | High-capacity UPQC and control method thereof |
| CN103647278A (en) * | 2013-12-18 | 2014-03-19 | 国家电网公司 | High-capacity unified power disturbance generating device |
| CN103997043A (en) * | 2014-05-15 | 2014-08-20 | 南京工程学院 | Uniform electricity quality regulator based on T-type three-level inverter and regulating method thereof |
| CN104065068A (en) * | 2014-05-23 | 2014-09-24 | 国家电网公司 | Short circuit control current limiter device |
| CN105119262A (en) * | 2015-09-21 | 2015-12-02 | 山东科汇电力自动化股份有限公司 | Circuit capable of simultaneously adjusting the quality of electric energy and performing active arc extinguishing on a low-current ground fault |
| CN108389681A (en) * | 2018-02-01 | 2018-08-10 | 清华大学 | The transformer device structure of degree of coupling enhancing |
| CN110460056A (en) * | 2019-08-01 | 2019-11-15 | 太原理工大学 | The control method for coordinating of series compensation link and alternating current-direct current bus interface converter |
| WO2020000528A1 (en) * | 2018-06-25 | 2020-01-02 | 全球能源互联网研究院有限公司 | Ring network controller and power distribution network |
| CN111313424A (en) * | 2020-03-27 | 2020-06-19 | 西安交通大学 | Three-phase four-wire system universal power quality controller and control method thereof |
| WO2021036147A1 (en) * | 2019-08-30 | 2021-03-04 | 国网安徽省电力有限公司铜陵供电公司 | Active power filter |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103618310A (en) * | 2013-12-05 | 2014-03-05 | 国家电网公司 | High-capacity UPQC and control method thereof |
| CN103647278A (en) * | 2013-12-18 | 2014-03-19 | 国家电网公司 | High-capacity unified power disturbance generating device |
| CN103997043A (en) * | 2014-05-15 | 2014-08-20 | 南京工程学院 | Uniform electricity quality regulator based on T-type three-level inverter and regulating method thereof |
| CN104065068A (en) * | 2014-05-23 | 2014-09-24 | 国家电网公司 | Short circuit control current limiter device |
| CN105119262A (en) * | 2015-09-21 | 2015-12-02 | 山东科汇电力自动化股份有限公司 | Circuit capable of simultaneously adjusting the quality of electric energy and performing active arc extinguishing on a low-current ground fault |
| CN108389681A (en) * | 2018-02-01 | 2018-08-10 | 清华大学 | The transformer device structure of degree of coupling enhancing |
| CN108389681B (en) * | 2018-02-01 | 2020-01-24 | 清华大学 | Transformer structure with enhanced coupling degree |
| WO2020000528A1 (en) * | 2018-06-25 | 2020-01-02 | 全球能源互联网研究院有限公司 | Ring network controller and power distribution network |
| CN110460056A (en) * | 2019-08-01 | 2019-11-15 | 太原理工大学 | The control method for coordinating of series compensation link and alternating current-direct current bus interface converter |
| CN110460056B (en) * | 2019-08-01 | 2023-03-17 | 太原理工大学 | Coordination control method for series compensation link and AC/DC bus interface converter |
| WO2021036147A1 (en) * | 2019-08-30 | 2021-03-04 | 国网安徽省电力有限公司铜陵供电公司 | Active power filter |
| CN111313424A (en) * | 2020-03-27 | 2020-06-19 | 西安交通大学 | Three-phase four-wire system universal power quality controller and control method thereof |
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