CN204441903U - A kind of clean energy resource system of alternating current-direct current mixing - Google Patents

A kind of clean energy resource system of alternating current-direct current mixing Download PDF

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CN204441903U
CN204441903U CN201520058747.2U CN201520058747U CN204441903U CN 204441903 U CN204441903 U CN 204441903U CN 201520058747 U CN201520058747 U CN 201520058747U CN 204441903 U CN204441903 U CN 204441903U
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bus
transmission line
generator
direct current
power transmission
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谢宝忠
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South China University of Technology SCUT
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/50Photovoltaic [PV] energy
    • Y02E10/56Power conversion systems, e.g. maximum power point trackers

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Abstract

The utility model discloses the clean energy resource system of a kind of alternating current-direct current mixing, comprise multiple stage double-fed asynchronous generator, its stator winding is connected with ac bus, and rotor windings connects DC bus by current transformer; Ac bus export alternating current after transformer boost direct output AC and/or connect again after transformer boost DC converter output direct current.The electrical power that stator winding exports is incorporated to transmission line of alternation current through ac bus, transformer; When double-fed asynchronous generator is in the operation of supersynchronous state, electrical power is outputted to DC bus through current transformer by rotor windings, and when double-fed asynchronous generator is in metasynchronism or synchronous regime runs, rotor windings absorbs electrical power through current transformer from DC bus; Native system make full use of double-fed asynchronous, synchronous, between DC generator, photovoltaic generation etc., space-time is complementary, reduce unstable clean energy resource power fluctuation to electric network influencing, reduce reserve capacity of power grid, improve operation of power networks stability.

Description

A kind of clean energy resource system of alternating current-direct current mixing
Technical field
The utility model relates to clean energy resource system, particularly relates to the clean energy resource system of a kind of alternating current-direct current mixing.
Background technology
Along with the anxiety of current energy source, the exploitation of the multiple new forms of energy such as wind energy, solar energy, tidal energy and wave energy obtains increasing attention, in the exploitation of these new forms of energy, employ double-fed asynchronous generator, synchronous generator, DC generator and photovoltaic power generation equipment widely.In order to improve by wind energy, the efficient energy conversion of prime mover that tidal energy and wave energy etc. drive, the rotating speed of prime mover can change within the scope of certain, the double-fed asynchronous generator driven by it, the rotating speed of synchronous generator changes thereupon, the frequency of its electrical power also changes, just can need be connected to the grid through current transformer, cause its electrical power unstable, harmonic content is high, the electrical power that DC generator and photovoltaic power generation equipment send is connected to the grid through current transformer mostly, because these new forms of energy have unsteadiness, the feature of randomness, the quality of power supply that it is sent is low, larger on the impact of electrical network after being connected to the grid, sometimes even these energy to be abandoned, cause larger waste.The part generate electricity machine receiving the own characteristic such as scarce capacity and new forms of energy instability to cause due to electrical network suspends, ration the power supply and cause electric field performance driving economy to decline, the main cause of rationing the power supply is a grid-connected difficult problem, new forms of energy are exerted oneself instability, other power supplys are needed to provide free peak regulation service for it, the peak regulation such as pumped storage, fuel gas generation, variable frequency power source need be built, when peak is in short supply, to ration the power supply especially severe, optimization planning power supply architecture and electrical network layout, expand wind electricity digestion market, also need by scientific and technical innovation, promote the coordination of wind-powered electricity generation production and consumption.
Summary of the invention
The purpose of this utility model is the shortcoming and defect overcoming above-mentioned prior art, provides the clean energy resource system that a kind of alternating current-direct current mixes.During reduction new forms of energy power fluctuation, generating equipment power output is on the impact of electrical network, reduces the harmonic injection to electrical network, improves the stability of operation of power networks; The power stage of instability then realizes power-balance by the switching of load, is stored by the Conversion of Energy of instability or consumes, and substitute bavin firewood, stalk, coal and oil equal energy source for other forms, reduces charcoal discharge, reduces environmental pollution.
The utility model is achieved through the following technical solutions:
A clean energy resource system for alternating current-direct current mixing, comprises ac bus, DC bus and electricity generation system, and described electricity generation system comprises multiple stage double-fed asynchronous generator, prime mover for driving each double-fed asynchronous generator to operate;
The stator winding of described double-fed asynchronous generator is connected with ac bus, and rotor windings connects DC bus by current transformer;
The alternating current that described ac bus exports direct output AC and/or connect DC converter output direct current after transformer boost again after transformer boost.
Described electricity generation system also comprises multiple stage by the synchronous generator of prime mover driven and DC generator; Exchange conversion is connect DC bus after direct current by AC/DC by described synchronous generator; DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by described DC generator.
Described electricity generation system also comprises photovoltaic generating system, and DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by photovoltaic generating system.
Between ac bus and DC bus, be also connected with the AC/DC converter for being exchanged by bidirectional electric energy between DC bus and ac bus.
Described DC bus also be connected water electrolysis equipment and electroheat equipment; Described water electrolysis equipment connects hydrogen supply oxygen supply equipment, and described electroheat equipment connects heat supply heating equipment.
Described clean energy resource system also comprises DC power transmission line, between DC bus and DC power transmission line, is also connected with for the DC/DC converter by the direct voltage conversion between DC bus and DC power transmission line and electric energy two-way exchange.
Described clean energy resource system also comprises overlaps synchronous generator, DC generator and photovoltaic generating system more;
Exchange conversion is connect DC power transmission line after direct current by AC/DC by described synchronous generator; DC voltage conversion is be connected DC power transmission line after galvanic current pressure respectively by DC/DC by described DC generator and photovoltaic generating system;
In described DC power transmission line, be also connected with for absorbing electrical power from DC power transmission line, and carry out according to the electrical power being input to DC power transmission line the metallide equipment that switching realizes power-balance;
Described DC power transmission line being also connected with, for absorbing electrical power from DC power transmission line, and carrying out according to the electrical power being input to DC power transmission line the DC load that switching realizes power-balance;
Described DC power transmission line is also connected to, rural area minisize distributed type air feed heating subsystem, town region air feed heating subsystem, city central gas supply heating subsystem and hydrogen energy source automobile hydrogen supply subsystem.
Described prime mover comprises wind energy conversion system, heat engine, the hydraulic turbine.
The control method of the clean energy resource system of alternating current-direct current mixing is as follows:
Prime mover driven double-fed asynchronous generator rotates, and the electrical power that stator winding exports is incorporated to transmission line of alternation current through ac bus, transformer, or is incorporated to DC power transmission line after the DC converter change of current;
When double-fed asynchronous generator is in the operation of supersynchronous state, electrical power is outputted to DC bus through current transformer by rotor windings, and when double-fed asynchronous generator is in metasynchronism or synchronous regime runs, rotor windings absorbs electrical power through current transformer from DC bus;
Now, the alternating current that ac bus exports is directly incorporated into transmission line of alternation current after transformer boost, and/or is incorporated to DC power transmission line after being converted to direct current by DC converter.
The utility model, relative to prior art, has following advantage and effect:
The utility model controls (or operation), and method is simple, is easy to realize.
The utility model is according to the running status of double-fed asynchronous generator, motor stator winding (coil) is exported more stable active power and is incorporated to AC network (ac bus), and rotor windings (coil) is accessed direct current system (DC bus), and with its exchange power, power-balance is realized by the switching of load, be other forms of energy storage by the electric energy conversion of instability or consume, and substitute bavin firewood, stalk, coal and oil equal energy source, reduce charcoal discharge, reduce environmental pollution, reduce generation of electricity by new energy power output to the impact of electrical network, reduce the harmonic injection to electrical network, double-fed wind power generator group even can be made as the normal power of electrical network, improve the stability of operation of power networks.
When double-fed asynchronous generator rotor when synchronous and metasynchronism state is run absorbs electrical power from direct current component (DC bus); When double-fed asynchronous generator group is run with supersynchronous state, the electric energy that rotor exports is outputted to direct current component.The power fluctuation exported due to the stator winding of double-fed asynchronous generator is less, make the electrical power of double-fed asynchronous generator stator side stable output in the comparatively broad range of speeds, the larger electrical power that fluctuates then is exchanged through current transformer and direct current component by rotor windings.The power-balance of direct current component is realized by the switching of water electrolysis equipment, electroheat equipment, metallide equipment and other DC load.
As mentioned above, native system and control method thereof, technological means is simple and easy to do, the space-time that can make full use of between double-fed asynchronous generator in system, synchronous generator, DC generator, photovoltaic generation is complementary, reduce unstable clean energy resource power fluctuation to the impact of electrical network, reduce the reserve capacity of electrical network, improve the stability of operation of power networks; The DC load such as water electrolysis equipment, electroheat equipment of direct current component replaces firewood straw with rural area minisize distributed type hydrogen supply heat-supplying mode, replaces coal coal gas with the centralized hydrogen supply heat-supplying mode in city and town region, replace with hydrogen energy source the modes such as motor vehicle fuel to reduce carbon emission, reduces environmental pollution.
Accompanying drawing explanation
Fig. 1 is the utility model block diagram and control (or operation) method flow schematic diagram.
Embodiment
Below in conjunction with specific embodiment, the utility model is more specifically described in detail.
Embodiment
As shown in Figure 1.The clean energy resource system of the utility model alternating current-direct current mixing, comprises ac bus, DC bus and electricity generation system, and described electricity generation system comprises multiple stage double-fed asynchronous generator, prime mover for driving each double-fed asynchronous generator to operate;
The stator winding of described double-fed asynchronous generator is connected with ac bus, and rotor windings connects DC bus by current transformer;
The alternating current that described ac bus exports direct output AC and/or connect DC converter output direct current after transformer boost again after transformer boost.Realizing ac bus with exchanging exports voltage transitions between (interchange outlet line) and Power Exchange, realizes AC-DC conversion and Power Exchange that ac bus and DC converter, direct current export (DC leadout road).
Described electricity generation system also comprises multiple stage by the synchronous generator of prime mover driven and DC generator; Exchange conversion is connect DC bus after direct current by AC/DC by described synchronous generator; The electrical power that synchronous generator exports delivers to DC bus through AC/DC.
DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by described DC generator; The electrical power that DC generator exports delivers to DC bus through DC/DC.
Described electricity generation system also comprises photovoltaic generating system, and DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by photovoltaic generating system; The electrical power that photovoltaic generating system exports delivers to DC bus through DC/DC.
Between ac bus and DC bus, being also connected with the AC/DC converter for being exchanged by bidirectional electric energy between DC bus and ac bus, exchanging for the bidirectional electric energy realized between DC bus and ac bus.
Described DC bus also be connected water electrolysis equipment and electroheat equipment; Described water electrolysis equipment connects hydrogen supply oxygen supply equipment, and described electroheat equipment connects heat supply heating equipment; Absorb electrical power from DC bus and produce heat energy and hydrogen and oxygen, and carry out switching according to the electrical power being input to DC bus and realize power-balance.
The electric energy connecting the output of the synchronous generator of DC bus, DC generator and photovoltaic generating system is converted to through AC/DC or DC/DC the current transformer (not shown) sharing after direct current and connect double-fed asynchronous generator rotor-side; Or share the two-way AC/DC (not shown) connected between ac bus and DC bus.This two schemes, according to the demand of electrical network, can utilize the characteristic of clean energy resource spatial and temporal distributions, reduces the current transformer total capacity of system.
Described clean energy resource system also comprises DC power transmission line, between DC bus and DC power transmission line, is also connected with for the DC/DC converter by the direct voltage conversion between DC bus and DC power transmission line and electric energy two-way exchange.
Described clean energy resource system also comprises overlaps synchronous generator, DC generator and photovoltaic generating system more;
Exchange conversion is connect DC power transmission line after direct current by AC/DC by described synchronous generator, is incorporated to DC power transmission line for the electric energy sent by synchronous generator through AC/DC.DC voltage conversion is be connected DC power transmission line after galvanic current pressure respectively by DC/DC by described DC generator and photovoltaic generating system, is incorporated to DC power transmission line for the electric energy sent by photovoltaic generating system through DC/DC.
In described DC power transmission line, be also connected with for absorbing electrical power from DC power transmission line, and carry out according to the electrical power being input to DC power transmission line the metallide equipment that switching realizes power-balance;
Described DC power transmission line being also connected with, for absorbing electrical power from DC power transmission line, and carrying out according to the electrical power being input to DC power transmission line the DC load (other loads) that switching realizes power-balance;
Described DC power transmission line is also connected to, rural area minisize distributed type air feed heating subsystem, town region air feed heating subsystem, city central gas supply heating subsystem and hydrogen energy source automobile hydrogen supply subsystem.
Described rural area minisize distributed type air feed heating subsystem, heat energy and hydrogen and oxygen is produced for absorbing electrical power from connection DC power transmission line, replace fuel wood stalk, coal equal energy source, and carry out switching according to the electrical power being input to DC power transmission line and realize power-balance.
Described town region air feed heating subsystem, producing heat energy and hydrogen and oxygen for absorbing electrical power from connection DC power transmission line, replacing fuel wood stalk, coal equal energy source, and carries out switching according to the electrical power being input to DC power transmission line and realize power-balance.
Described city central gas supply heating subsystem, producing heat energy and hydrogen and oxygen for absorbing electrical power from connection DC power transmission line, replacing coal, coal gas equal energy source, and carries out switching according to the electrical power being input to DC power transmission line and realize power-balance.
Described hydrogen energy source automobile hydrogen supply subsystem, producing and hydrogen and oxygen for absorbing electrical power from connection DC power transmission line, replacing petroleum resources, and carrying out switching according to the electrical power being input to DC power transmission line and realize power-balance.
Described prime mover comprises wind energy conversion system, heat engine, the hydraulic turbine etc.
Control (or operation) method of the clean energy resource system of alternating current-direct current mixing realizes by following step:
Prime mover driven double-fed asynchronous generator rotates, and the electrical power that stator winding exports is incorporated to transmission line of alternation current through ac bus, transformer, or is incorporated to DC power transmission line after the DC converter change of current;
When double-fed asynchronous generator is in the operation of supersynchronous state, electrical power is outputted to DC bus through current transformer by rotor windings, and when double-fed asynchronous generator is in metasynchronism or synchronous regime runs, rotor windings absorbs electrical power through current transformer from DC bus;
Now, the alternating current that ac bus exports is directly incorporated into transmission line of alternation current after transformer boost, and/or is incorporated to DC power transmission line after being converted to direct current by DC converter.
In addition, photovoltaic generating system, DC generator (etc. DC generation equipment) and the synchronous generator of other prime mover driven can be corresponding by AC/DC or DC/DC current transformer, electric energy is outputted to direct current component (DC bus), double-fed asynchronous generator rotor windings, water electrolysis equipment, electroheat equipment, metallide equipment and other DC load run for synchronous and metasynchronism state provide electrical power; Also electrical network can be directly incorporated into through current transformer; Water electrolysis equipment, electroheat equipment, metallide equipment and other DC load are connected to direct current component for absorbing electrical power, and realize the power-balance of direct current component according to the timely switching of the running status of each generating equipment.
As mentioned above, just the utility model can be realized preferably.
Double-fed asynchronous generator in the utility model is equally applicable to brushless double feed generator, and now stator coil corresponds to the power winding of brushless double feed generator, and rotor coil corresponds to the controlled winding of brushless double feed generator.
Execution mode of the present utility model is not restricted to the described embodiments; other are any do not deviate from Spirit Essence of the present utility model and principle under do change, modification, substitute, combine, simplify; all should be the substitute mode of equivalence, be included within protection range of the present utility model.

Claims (9)

1. a clean energy resource system for alternating current-direct current mixing, comprises ac bus, DC bus and electricity generation system, it is characterized in that, described electricity generation system comprises multiple stage double-fed asynchronous generator, prime mover for driving each double-fed asynchronous generator to operate;
The stator winding of described double-fed asynchronous generator is connected with ac bus, and rotor windings connects DC bus by current transformer;
The alternating current that described ac bus exports direct output AC and/or connect DC converter output direct current after transformer boost again after transformer boost.
2. the clean energy resource system of alternating current-direct current mixing according to claim 1, is characterized in that, described electricity generation system also comprises multiple stage by the synchronous generator of prime mover driven and DC generator; Exchange conversion is connect DC bus after direct current by AC/DC by described synchronous generator; DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by described DC generator.
3. the clean energy resource system of alternating current-direct current mixing according to claim 2, it is characterized in that, described electricity generation system also comprises photovoltaic generating system, and DC voltage conversion is connect DC bus after galvanic current pressure by DC/DC by photovoltaic generating system.
4. the clean energy resource system of alternating current-direct current mixing according to any one of claims 1 to 3, is characterized in that, between ac bus and DC bus, is also connected with the AC/DC converter for being exchanged by bidirectional electric energy between DC bus and ac bus.
5. the clean energy resource system of alternating current-direct current mixing according to claim 4, is characterized in that, described DC bus also connects water electrolysis equipment and electroheat equipment respectively; Described water electrolysis equipment connects hydrogen supply oxygen supply equipment, and described electroheat equipment connects heat supply heating equipment.
6. the clean energy resource system of alternating current-direct current mixing according to claim 4, it is characterized in that, the electric energy connecting the output of the synchronous generator of DC bus, DC generator and photovoltaic generating system is converted to through AC/DC or DC/DC the current transformer sharing connection double-fed asynchronous generator rotor-side after direct current and exports ac bus to; Or share the two-way AC/DC connected between ac bus and DC bus, export electric energy to ac bus.
7. the clean energy resource system of alternating current-direct current mixing according to claim 4, it is characterized in that, described clean energy resource system also comprises DC power transmission line, between DC bus and DC power transmission line, be also connected with for the DC/DC converter by the direct voltage conversion between DC bus and DC power transmission line and electric energy two-way exchange.
8. the clean energy resource system of alternating current-direct current mixing according to claim 6, it is characterized in that, described clean energy resource system also comprises overlaps synchronous generator, DC generator and photovoltaic generating system more;
Exchange conversion is connect DC power transmission line after direct current by AC/DC by described synchronous generator; DC voltage conversion is be connected DC power transmission line after galvanic current pressure respectively by DC/DC by described DC generator and photovoltaic generating system;
In described DC power transmission line, be also connected with for absorbing electrical power from DC power transmission line, and carry out according to the electrical power being input to DC power transmission line the metallide equipment that switching realizes power-balance;
Described DC power transmission line being also connected with, for absorbing electrical power from DC power transmission line, and carrying out according to the electrical power being input to DC power transmission line the DC load that switching realizes power-balance;
Described DC power transmission line is also connected to, rural area minisize distributed type air feed heating subsystem, town region air feed heating subsystem, city central gas supply heating subsystem and hydrogen energy source automobile hydrogen supply subsystem.
9. the clean energy resource system of alternating current-direct current mixing according to claim 4, it is characterized in that, described prime mover is wind energy conversion system, heat engine or the hydraulic turbine.
CN201520058747.2U 2015-01-27 2015-01-27 A kind of clean energy resource system of alternating current-direct current mixing Active CN204441903U (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104682427A (en) * 2015-01-27 2015-06-03 华南理工大学 AC-DC (Alternating Current-Direct Current) hybrid clean energy source system and method
CN113169551A (en) * 2018-09-28 2021-07-23 西门子能源全球有限两合公司 Energy supply system for a wading installation having a first and a second winding system of a generator system for feeding different direct voltage busbars

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104682427A (en) * 2015-01-27 2015-06-03 华南理工大学 AC-DC (Alternating Current-Direct Current) hybrid clean energy source system and method
CN113169551A (en) * 2018-09-28 2021-07-23 西门子能源全球有限两合公司 Energy supply system for a wading installation having a first and a second winding system of a generator system for feeding different direct voltage busbars
CN113169551B (en) * 2018-09-28 2024-01-23 西门子能源全球有限两合公司 Energy supply system for a wading installation with a first and a second winding system of a generator system for feeding different dc voltage buses

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