CN204089213U - Wide speed range directly-driving wind power generation system - Google Patents
Wide speed range directly-driving wind power generation system Download PDFInfo
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- CN204089213U CN204089213U CN201420425322.6U CN201420425322U CN204089213U CN 204089213 U CN204089213 U CN 204089213U CN 201420425322 U CN201420425322 U CN 201420425322U CN 204089213 U CN204089213 U CN 204089213U
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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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
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Abstract
The utility model provides a kind of wide speed range directly-driving wind power generation system, the wind-driven generator comprise wind energy conversion system, being connected with wind energy conversion system, the armature winding of described wind-driven generator is connected with controllable rectifying device, described controllable rectifying device is connected with DC bus, and DC bus is connected with electrical network by inverter; The excitation winding of described wind-driven generator is connected with standard sine wave field power supply, and standard sine wave field power supply is connected with DC bus.The utility model can control the amplitude of excitation field, rotating speed and rotary speed direction by regulating exciting voltage, excitation frequency and excitation phase sequence; in the wind speed range that can generate electricity; all electricity generation system can be controlled at best power operating point, and when being conducive to fault, protecting control strategy realizes.
Description
Technical field
The utility model Control Technology of Wind Power Generation System field, particularly relates to a kind of wide speed range directly-driving wind power generation system.
Background technology
Dual feedback wind power generation system and permanent magnet direct-drive wind generator system are the main generation modes of wind power generation field, the rotor side of dual feedback wind power generation system is all connected with electrical network, belong to strongly coupled system, and strongly coupled system when the grid fails, the low voltage crossing protecting control of system is difficult to realize, and speed increasing gear unit makes, and system bulk is comparatively large, Generation System Reliability is deteriorated, and can generate electricity in wind speed range, electricity generation system can not be in optimal operating condition all the time; And there is the excessive and a large amount of use rare earth permanent-magnetic material problem of generator volume in directly-drive permanent magnet wind generating system, and a certain specific rotation speeds can only be run in constant-speed and constant-frequency operational mode, when wind speed changes, the power coefficient of blower fan departs from maximum, causes operational efficiency decline, wind energy resources waste.
Utility model content
The purpose of this utility model is the while of using wind energy to obtain electric energy to greatest extent; dual feedback wind power generation system rotor side can be solved directly be connected close coupling with electrical network and cause protecting Problems existing when comprising electrical network and electricity generation system fault; as low voltage crossing problem, and adopt AC excitation with avoid a large amount of rare earth permanent-magnetic material of permanent magnet direct-drive wind generator system consumption and bring because permanent magnet direct-drive exciter current of generator is uncontrollable rotating speed range of operation narrow cause generator can not real time execution in the problem of best power point.
A kind of wide speed range directly-driving wind power generation system, the wind-driven generator comprise wind energy conversion system, being connected with wind energy conversion system, also comprises:
Controlled rectification unit, its input is connected with the armature winding of wind-driven generator, exports, be stored in the electric capacity of DC bus for the electric energy rectification sent by wind-driven generator;
DC bus unit, its input is connected with the output of controlled rectification unit, exports the Buffer Pool of electric energy for the electric energy that exports as generator and inverter to electrical network;
Inverter, its input is connected with the output of DC bus unit, and the electric energy be stored on dc-link capacitance through controlled rectification for being sent by generator converts the controlled industrial-frequency alternating current of power factor to and exports the electrical network be attached thereto to;
Standard sine wave field power supply, its input is connected with DC bus, its output is connected with excitation winding by AC excitation wind power generator rotor three-phase slip-ring.
Further, wide speed range directly-driving wind power generation system as above, wind-driven generator is AC excitation wind-driven generator, and its number of poles is more than or equal to 8 poles, and rotor-side has three phase excitation winding.
Further, wide speed range directly-driving wind power generation system as above, described controlled rectification unit is the rectification unit be made up of power device IGBT or thyristor topological structure, and the input of this unit is connected with described AC excitation wind-driven generator three-phase output end, its output is connected with DC bus.
Further, wide speed range directly-driving wind power generation system as above, described standard sine wave field power supply comprises SPWM frequency converter, broadband LC filter.
Beneficial effect:
The wide speed range that the utility model provides runs the Grazing condition wind generator system of large rotating inertia AC excitation, its substantive characteristics is the circular rotational speed of magnetic field that electricity generation system is formed according to wind field wind speed determination AC excitation, and the rotating speed in magnetic field can be added with generator mechanical rotating speed or subtract each other to ensure that wind generator system runs on best operating point.Electricity generation system adopts the structure of common DC bus Energizing unit and generator windings and electrical network to be isolated, and solves the defect of dual feedback wind power generation system and electrical network close coupling and the narrow problem of directly-drive permanent magnet wind generating system rotating speed range of operation.The amplitude of excitation field, rotating speed and rotary speed direction can be controlled by regulating exciting voltage, excitation frequency and excitation phase sequence; in the wind speed range that can generate electricity; all electricity generation system can be controlled at best power operating point, and when being conducive to fault, protecting control strategy realizes.
Accompanying drawing explanation
Fig. 1 is the utility model wide speed range directly-driving wind power generation system structural representation.
Embodiment
For making the purpose of this utility model, technical scheme and advantage clearly, below technical scheme in the utility model be clearly and completely described, obviously, described embodiment is the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.
Fig. 1 is the utility model wide speed range directly-driving wind power generation system structural representation, and as shown in Figure 1, native system comprises: the wind-driven generator comprise wind energy conversion system, being connected with wind energy conversion system, also comprises:
Controlled rectification unit, its input is connected with the armature winding of wind-driven generator, exports, be stored in the electric capacity of DC bus for the electric energy rectification sent by wind-driven generator;
DC bus unit, its input is connected with the output of controlled rectification unit, exports the Buffer Pool of electric energy for the electric energy that exports as generator and inverter to electrical network;
Inverter, its input is connected with the output of DC bus unit, and the electric energy be stored on dc-link capacitance through controlled rectification for being sent by generator converts the controlled industrial-frequency alternating current of power factor to and exports the electrical network be attached thereto to;
Standard sine wave field power supply, its input is connected with DC bus, its output is connected with excitation winding by AC excitation wind power generator rotor three-phase slip-ring.
Particularly, the utility model wind generator system is made up of inverter, DC bus, standard sine wave variable frequency excitation power supply, wind energy conversion system, wind-driven generator and controlled rectification unit, and wherein inverter, field power supply, controlled rectification unit and DC bus form common DC bus structure.Wind energy conversion system, generator and field power supply wherein can be selected to be installed on tower, to reduce tower weight, to facilitate the maintenance of system.
The effect of inverter is that the alternating current that the electric energy be stored on dc-link capacitance through controlled rectification sent by generator converts the controlled power frequency 690V of power factor to exports the electrical network be attached thereto to.
DC bus is connected to copper bar by one group of Capacitance parallel connection and forms, and for electrical power storage, the electric energy exported as generator and inverter export the Buffer Pool of electric energy to electrical network, make wind-driven generator on electrically with electrical network decoupling zero.
Standard sine wave variable frequency excitation power supply provides excitation, its frequency range (0,100) Hz, voltage range [0,690] V for generator amature excitation winding, and frequency and voltage all can independent regulation.Exciting voltage and frequency size control according to generator speed and generator output voltage.The rotating speed of excitation field is controlled by excitation frequency, and the size of excitation field is controlled by exciting voltage, and the direction of rotation of excitation field is by the phase sequence control of three phase excitation voltage.
Wind resource change is mechanical energy by wind energy conversion system, and wind energy conversion system rotating part connects with generator coaxle, to generator input mechanical output, regulates wind machine oar leaf wind-engaging angle can control the rotating speed of generator and the input torque of generator under wind-force certain condition.
The mechanical energy that wind energy conversion system inputs is converted to electric energy by direct wind-driven generator.The number of poles of this generator is more than or equal to 8 poles, and rotor-side has three phase excitation winding, and its moment of inertia is larger than the moment of inertia of double-fed generator.
Controlled rectification unit is that the electric energy rectification sent by generator exports, and is stored in the electric capacity of DC bus.
Different from existing dual feedback wind power generation system, the excitation of generator inputs by common DC bus structure, generator electric energy exports to keep apart with electrical network and achieves flexibly connecting of wind generator system and electrical network.Excitation system and the generator output that can realize generator in dual feedback wind power generation system cause the insoluble problem of low voltage crossing with the close coupling characteristic of electrical network; This wind generator system is the wind generator system of wind energy conversion system direct drive generator, eliminates the speed increasing gear unit of dual feedback wind power generation system.
Different from directly-drive permanent magnet wind generating system, common DC bus structure realizes generator and is connected with power grid flexible that can to solve excitation frequency when electric network fault causes line voltage to reduce unadjustable, the increase of generator system mechanical separator speed causes generator voltage to raise, the problem that DC bus-bar voltage raises, because the exciting current size of the wind generator system involved by the utility model and frequency are all controlled, the size of excitation field can be realized according to system conditions, the rotary speed of excitation field and the control in direction, and the electric regulating time of Energizing unit is far smaller than the mechanical time of wind machine oar leaf angular adjustment,
The flywheel energy storage function of electricity generation system mechanical rotating parts can be made full use of in grid side failure recovery time, regulating the size of exciting current and frequency that generator speed is raised, is the rotation function of wind energy conversion system rotating parts and generator amature by wind energy storage; In grid side failure recovery time, the rotating speed of generator exceedes mechanical separator speed when requiring, the electromagnetic torque that can control generator by controlled rectification unit in generator and Energizing unit cooperation control, the mechanical output regulating the angle of blade to reduce generator input to suppress generator speed to raise further.
The utility model wind generator system adopts common DC bus structure the rotor field coil of generator, generator armature winding and electrical network to be kept apart to achieve flexibly connecting of wind generator system and electrical network.Generator excitation winding supplies exciting voltage by being connected to standard sine wave variable frequency power supply on DC bus; The electric energy that generator armature winding sends in the electric capacity that controlled rectification cell translation becomes direct current energy to be stored on DC bus, the wherein controlled rectification unit rectifying device that can be made up of IGBT or thyristor topological structure; Inverter unit exports the electric energy inversion be stored in dc-link capacitance to electrical network.
Generator amature side adopts 3 phase sine wave AC excitations, and exciting voltage and excitation frequency are adjustable according to rotor speed; Turning to of excitation field can be identical with rotor speed direction or contrary, adds the running speed scope of electricity generation system.According to the blade angle of wind energy conversion system and the rotating speed n1 of wind energy conversion system rotating shaft in wind field wind condition determination Fig. 1; Need the frequency of the exciting current exported to obtain the rotating speed n2 in AC excitation magnetic field and to turn to according to field power supply in the known Fig. 1 of n1; According to the known size meeting the exciting current of wind turbine power generation in Fig. 1 of n1.Therefore, wind generator system, in the wind speed range that can generate electricity, all can control at best power operating point by the wind generator system involved by the utility model, and is conducive to the realization of low voltage crossing protecting control strategy.
The number of poles driving AC excitation wind-driven generator is more than or equal to 8, and therefore, moment of inertia is large, can, to suppress the change of system rotating speed, therefore utilize its flywheel energy storage effect can reduce the mechanical shock of wind-force sudden change to electricity generation system.
The purpose of this utility model is the while of using wind energy to obtain electric energy to greatest extent, dual feedback wind power generation system rotor side can be solved directly be connected close coupling with electrical network and cause protecting Problems existing when comprising electrical network and electricity generation system fault, as low voltage crossing problem, with a large amount of rare earth permanent-magnetic material of permanent magnet direct-drive wind generator system consumption and exciter current of generator uncontrollable bring rotating speed range of operation narrow cause generator can not real time execution in the problem of best power point, as constant-speed and constant-frequency mode can only run on a certain specific rotation speeds, when wind speed changes, the power coefficient of blower fan departs from maximum, operational efficiency is caused to decline, wind energy resources is wasted.Its substantive characteristics is that the controlled rectification unit of output winding in Fig. 1 of generator is connected with DC bus, and the electric energy that generator sends is exported to electrical network by inverter through DC bus; The effect of the field power supply in Fig. 1 only provides the excitation field of generator, and the wind powered generator system therefore involved by the utility model and electrical network are for flexibly connecting.During low speed, the same winding switch that is in parallel of generator armature winding is that windings in series is to increase the armature winding number of turn, combine again control field power supply output frequency can guarantee generator export electric energy simultaneously electricity generation system can run on best operating point, because this increasing the rotating speed range of operation of the wind generator system involved by the utility model.
The wind-force excursion of specific wind field is large, wind energy conversion system maximum efficiency can change under different wind friction velocity, namely the generator power under different wind speed and there is confirmable relation between wind energy conversion system best power, need to regulate blade aperture to control generator amature rotating speed according to wind speed, make generator operation in best power state.And the running speed scope of dual feedback wind power generation system and directly-drive permanent magnet wind generating system is narrower, particularly the running speed scope of directly-drive permanent magnet wind generating system is narrower, can not make full use of wind energy.The wide speed range directly-driving wind power generation system that the utility model relates to utilizes the frequency conversion function of standard sine wave variable frequency excitation power supply and the change of generator armature winding construction that generator can be made in low wind speed range also to operate in best power point, realize the function using wind energy to greatest extent, namely specific wind field wind speed is within the scope of low wind speed, middle wind speed and high wind speed, all electricity generation system can be controlled at best power operating point.
The maximum advantage of native system be electric energy that generator sends through controlled rectification using electrical power storage in the electric capacity of DC bus as buffering, be connected with electrical network through inverter again, when electric network fault, power-generating control system can regulate turning to of the amplitude of exciting voltage, frequency and control excitation field, allowing in the range of speeds of operation at electricity generation system machinery, is the kinetic energy of wind energy conversion system and generator rotating parts in Fig. 1 unit by wind energy storage; Reactive power is injected to electrical network by inverter.
The running speed wide ranges of native system, system can, according to real-time wind-force feature, make system cloud gray model in best effort operating mode by control.Because generator in electricity generation system exports winding and excitation con-trol unit and electrical network thereof for flexibly connecting, the electric regulating time of exciting current and FREQUENCY CONTROL is far smaller than the mechanical system regulating time of wind machine oar leaf angle control mechanism, and native system significantly can improve the reliability of system.
Generating operation mode:
1, wind-force is weak, and during unit low cruise, system is according to optimum operation rotating speed, determine rotor-exciting frequency and exciting current, excitation field turn to turn to rotor identical, unit electrical loss be less than generator input mechanical output, system namely can to electrical network power output.
2, wind-force is strong, when generating unit speed raises, allows generating unit speed rise to optimum operation rotating speed, determines rotor-exciting frequency and exciting current, and excitation field turns to and turns to rotor identical, and system is to electrical network power output.
3, when generating unit speed is higher than synchronous speed, according to mechanical strength, determine unit optimum operation rotating speed, determine rotor-exciting frequency and exciting current, excitation field turns to and can turn to identical or contrary with rotor, and system is to electrical network power output.
Specific works principle:
1, system starts, when DC bus-bar voltage is zero, charged to DC bus by electrical network by the controlled rectification function of inverter, DC bus-bar voltage only needs rotor-exciting to work, set up power generator air gap magnetic field, generating unit speed is greater than zero, and generator continues to charge to rated voltage to DC bus by controlled rectification part, and now wind generator system has possessed the condition of generating.
2, system is normally run, according to the direction of rotation in the amplitude of generator mechanical rotating speed determination exciting current, frequency and magnetic field for generator provides excitation, the electric energy that generator sends through controlled rectification by power delivery to DC bus, the inverter be connected with DC bus is to the adjustable electric energy of electrical network output power factor.
Dual feedback wind power generation system exists and electrical network close coupling, when the grid fails, system protection controls to be difficult to realize and speed increasing gear unit makes that system bulk is comparatively large, Generation System Reliability variation, and can generate electricity in wind speed range, electricity generation system can not be in optimal operating condition all the time; There is the excessive and a large amount of use rare earth permanent-magnetic material problem of generator volume in directly-drive permanent magnet wind generating system, and a certain specific rotation speeds can only be run in constant-speed and constant-frequency operational mode, when wind speed changes, the power coefficient of blower fan departs from maximum, causes operational efficiency decline, wind energy resources waste; Along with reaching its maturity of the development of power electronic technology and computer technology and controlled rectification control technology and inversion transformation technique, the price of relevant device reduces gradually, more can embody advantage of the present utility model.
The defect that the Grazing condition wind generator system that wide speed range designed by the utility model runs large rotating inertia AC excitation adopts the structure of common DC bus Energizing unit and generator windings and electrical network to be isolated to solve dual feedback wind power generation system and electrical network close coupling and the narrow problem of directly-drive permanent magnet wind generating system rotating speed range of operation.The amplitude of excitation field, rotating speed and rotary speed direction can be controlled by regulating exciting voltage, excitation frequency and excitation phase sequence; in the wind speed range that can generate electricity; all electricity generation system can be controlled at best power operating point, and when being conducive to fault, protecting control strategy realizes.
Last it is noted that above embodiment is only in order to illustrate the technical solution of the utility model, be not intended to limit; Although be described in detail the utility model with reference to previous embodiment, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein portion of techniques feature; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the spirit and scope of each embodiment technical scheme of the utility model.
Claims (4)
1. a wide speed range directly-driving wind power generation system, the wind-driven generator comprise wind energy conversion system, being connected with wind energy conversion system, is characterized in that, also comprises:
Controlled rectification unit, its input is connected with the armature winding of wind-driven generator, exports, be stored in the electric capacity of DC bus for the electric energy rectification sent by wind-driven generator;
DC bus unit, its input is connected with the output of controlled rectification unit, exports the Buffer Pool of electric energy for the electric energy that exports as generator and inverter to electrical network;
Inverter, its input is connected with the output of DC bus unit, and the electric energy be stored on dc-link capacitance through controlled rectification for being sent by generator converts the controlled industrial-frequency alternating current of power factor to and exports the electrical network be attached thereto to;
Standard sine wave field power supply, its input is connected with DC bus, its output is connected with excitation winding by AC excitation wind power generator rotor three-phase slip-ring.
2. wide speed range directly-driving wind power generation system according to claim 1, is characterized in that, wind-driven generator is AC excitation wind-driven generator, and its number of poles is more than or equal to 8 poles, and rotor-side has three phase excitation winding.
3. wide speed range directly-driving wind power generation system according to claim 2, it is characterized in that, described controlled rectification unit is the rectification unit be made up of power device IGBT or thyristor topological structure, and the input of this unit is connected with described AC excitation wind-driven generator three-phase output end, its output is connected with DC bus.
4. wide speed range directly-driving wind power generation system according to claim 1, is characterized in that, described standard sine wave field power supply comprises SPWM frequency converter, broadband LC filter.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420425322.6U CN204089213U (en) | 2014-07-30 | 2014-07-30 | Wide speed range directly-driving wind power generation system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420425322.6U CN204089213U (en) | 2014-07-30 | 2014-07-30 | Wide speed range directly-driving wind power generation system |
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| CN204089213U true CN204089213U (en) | 2015-01-07 |
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| CN201420425322.6U Expired - Fee Related CN204089213U (en) | 2014-07-30 | 2014-07-30 | Wide speed range directly-driving wind power generation system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112152526A (en) * | 2020-09-27 | 2020-12-29 | 张明芬 | Pre-excitation current rotating speed response energy-saving control method for intelligent automobile generator |
| CN116404924A (en) * | 2023-06-09 | 2023-07-07 | 南方电网调峰调频发电有限公司检修试验分公司 | Control parameter adjusting device, method, device and medium of excitation system |
-
2014
- 2014-07-30 CN CN201420425322.6U patent/CN204089213U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112152526A (en) * | 2020-09-27 | 2020-12-29 | 张明芬 | Pre-excitation current rotating speed response energy-saving control method for intelligent automobile generator |
| CN112152526B (en) * | 2020-09-27 | 2022-11-29 | 浙江德宏汽车电子电器股份有限公司 | Pre-excitation current rotating speed response energy-saving control method for intelligent automobile generator |
| CN116404924A (en) * | 2023-06-09 | 2023-07-07 | 南方电网调峰调频发电有限公司检修试验分公司 | Control parameter adjusting device, method, device and medium of excitation system |
| CN116404924B (en) * | 2023-06-09 | 2023-09-08 | 南方电网调峰调频发电有限公司检修试验分公司 | Control parameter adjusting device, method, device and medium of excitation system |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150107 Termination date: 20160730 |
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| CF01 | Termination of patent right due to non-payment of annual fee |