CN201013531Y

CN201013531Y - Electric infinite variable speed double power stream wind generating set

Info

Publication number: CN201013531Y
Application number: CNU2007200331917U
Authority: CN
Inventors: 程明; 花为
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2007-01-05
Filing date: 2007-01-05
Publication date: 2008-01-30
Anticipated expiration: 2017-01-05

Abstract

The utility model is an electric nonpolar speed-adjusting double-power wind generator unit, which can adjust the rotating speed of the generator nonpolarly, make the rotating speed of the wind generator not changed with the change of the wind speed and realize the function of constant-frequency output with the changing wind speed. The electric nonpolar speed-adjustor (2) of the system comprises a stator (2.1), an external rotor (2.2), an inner rotor (2.3) and a slide ring (2.4). A wind power machine (1) is connected with the inner rotor (2.3) through an input axis (6); the slide ring (2.4) is arranged on the input axis; the external rotor (2.2) is arranged on the outer side of the inner rotor (2.3); the stator (2.1) is arranged on the outer side of the external rotor (2.2); the external rotor (2.2) is connected with a generator (3) through an output axis (7); a multi-phase wiring unit is arranged on the inner rotor (2.3), which is combined with an electrical brush to be connected on a first power convertor (5) through the slide ring (2.4). The stator (2.1) is also arranged on the multi-phase wiring unit, which is also connected with a second power convertor (4). The second power convertor (4) and the first power convertor (5) are connected with the same direct current power supply.

Description

Electric stepless speed change double power flow wind power generating set

Technical field

The utility model is a kind of rotating speed that can the step-less adjustment generator, and the rotating speed of wind-driven generator is not changed with change of wind velocity, realizes becoming the function of wind speed constant frequency output, belongs to the technical field that wind-driven generator is made.

Background technique

Along with the whole society to the giving more sustained attention of the energy and environmental problem, the development and use of renewable energy sources are just presenting the trend of accelerated development, wind energy extensively exists on earth and is to be one of the most ripe renewable energy sources of technology that people grasped at present.Wind power generating set is the device that in the wind-power generating system mechanical energy is converted into electric energy, it is the instrument that motive force is connected with the output electric energy, it not only directly has influence on the quality and the efficient of output electric energy, also has influence on the performance of whole wind power conversion system and the structure of device.Because wind energy is the lower a kind of energy of energy density, the wind energy conversion system that is driven by wind energy is operated in lower rotating speed (tens rev/mins), traditional synchronous or induction generator is because the number of poles restriction, rotating speed is all higher usually, therefore, the wind-power generating system of main flow all adopts mechanical overdrive gear between wind energy conversion system and generator at present.But overdrive gear not only volume is big and heavy, and needs often to safeguard, is link the weakest in the wind-power generating system.In recent years, direct driving wind-driven generator occurs, cancelled overdrive gear, therefore had advantages such as efficient height, dynamic response is fast, maintenance cost is low.Yet, because directly driving generator works under the low speed that per minute tens changes, for guaranteeing its output voltage (30-80Hz) in the scope of normal frequency, generator need adopt bigger rotor diameter and more number of pole-pairs, has increased difficulty for the design and the manufacturing of generator.On the other hand, wind energy has randomness, suddenly big or suddenly small, present wind-power generating system, when wind speed during less than rated wind speed, wind wheel can absorb wind energy to greatest extent, and when wind speed is higher than a certain limit value, in order to keep generator output frequency substantially constant, adopt adjusting fan blade pitch to make wind wheel stall, to wind energy can not be fully utilized.Therefore, develop and to be suitable for wind energy effective conversion, reliable, efficient is high, control is convenient and power supply performance is good new-generation system, be the long-term pursuits of these those skilled in the art always.

Summary of the invention

Technical problem: the purpose of this utility model is to propose a kind of electric stepless speed change double power flow wind power generating set, this wind power generating set had both been cancelled step-up gear, can adopt conventional generator again, and make generator be operated in constant speed, realize real variable speed constant frequency operation.

Technological scheme: electric stepless speed change double power flow wind power generating set of the present utility model comprises wind energy conversion system, electric stepless gear, generator, second power inverter, five parts of first power inverter; Wherein electric stepless gear comprises stator, external rotor, internal rotor and slip ring; Wind energy conversion system connects internal rotor by input shaft, is provided with slip ring on input shaft; Periphery at internal rotor is provided with external rotor, is provided with stator in the periphery of external rotor; External rotor connects with generator by output shaft; Place polyphase windings on the internal rotor, be connected to first power inverter through slip ring and brush; Also place polyphase windings on the stator, and link to each other with second power inverter; Second power inverter and first power inverter are received same DC electrical source.The power of wind energy conversion system input is divided into mechanical output and two passages of electric power are delivered to output terminal, promptly so-called double power flow.Outer-rotor structure can be a cage-type rotor according to the difference of employing motor type, also can be p-m rotor or other patterns.

During work, wind energy conversion system drives internal rotor with angular velocity omega _wRotation when feeding electric current in internal rotor winding and the staor winding, by the electromagnetic coupling effect, will produce electromagnetic torque on the external rotor, drive external rotor with angular velocity omega _gRotation, thus drive the generator amature rotary electrification.Mechanical output by wind energy conversion system converts will be divided into two parts, and a part is that media is directly delivered to external rotor by internal rotor with the form of mechanical output with the electromagnetic field, be called mechanical output stream; Another part is with the form of electric power, by internal rotor winding, slip ring and brush, first power inverter, DC electrical source, second power inverter, is delivered to the mechanical output that staor winding is converted on the outer rotor shaft and removes to drive main generator, is called electrical power flow.The ratio of two kinds of power circuits can be controlled by two power inverters.

As ignore various losses and disregard, then the input power of speed changer (wind energy conversion system power) should equate with output power (being that generator changes power over to).But, if DC electrical source is made up of energy-storage units (battery, capacitor etc.), then the form of part input power with electric energy can be stored, in case of necessity, again the energy in the energy-storage units is delivered to staor winding through first power inverter 4, is converted to mechanical output and drives generator.So, when the mechanical output of wind energy conversion system and generator power balance each other, the then form transmission that all power can mechanical output, the electric power passage is transmitted power not; When wind energy conversion system power during, can be electrical power storage with unnecessary transformation of energy greater than the power of generator; Otherwise,, then the energy in the energy-storage units can be discharged the deficiency of replenishing input power when wind energy conversion system power during less than generator power.

Be added to size of current, frequency on electrical variable speed device staor winding and the internal rotor winding by control, rotating speed that can the step-less adjustment generator does not change the rotating speed of generator with change of wind velocity, realize becoming the output of wind speed constant frequency.Owing in this system mechanical output and two passages of electric power (double power flow) are arranged, when fluctuations in wind speed, unnecessary energy temporarily can be stored by the electric power passage, and when wind-force is not enough, again the electric energy that stores is discharged the driving generator, thereby improved the utilization ratio of wind energy greatly.

Beneficial effect:

1, removed mechanical step-up gear, simplified wind generating set structure, improved reliability, control flexibly.

2, no matter how wind speed changes, and by electric stepless speed change, can make generator be operated in rated speed, realizes the variable speed constant frequency operation.

3, electric energy is produced by conventional generator, without power electronic equipment, and no harmonic wave, the quality of power supply is good.

4, have mechanical output and electric power double power flow, unnecessary wind energy can be stored, discharge the driving generator in case of necessity again, Wind Power Utilization efficient height.

5, the electrical variable speed device can be used as starting motor, also can brake wind wheel.

Description of drawings

Fig. 1 is the constitutional diagram of the utility model electric stepless speed change double power flow wind power generating set, wherein have: wind energy conversion system 1, electric stepless gear 2, stator 2.1, external rotor 2.2, internal rotor 2.3, slip ring 2.4, generator 3, second power inverter 4, first power inverter 5, input shaft 6, output shaft 7.

Fig. 2 is the structural representation of the utility model electric stepless speed change double power flow wind power generating set.

Embodiment

Fig. 1 is the theory of constitution figure of this generator set, mainly is made up of five parts: wind energy conversion system 1, electric stepless gear (in the frame of broken lines) 2, generator 3, second power inverter, 4, the first power inverters 5; Wherein electric stepless gear 2 is critical components of this system, it is the motor of two arranged concentric in essence, this part comprises parts such as stator 2.1, external rotor 2.2, internal rotor 2.3 and slip ring 2.4, place heterogeneous (being 3 phases among the figure) winding on the internal rotor, be connected to first power inverter 5 through slip ring and brush; Also place polyphase windings (being 3 phases among the figure) on the stator, and link to each other with second power inverter 4; Outer-rotor structure can be a cage-type rotor according to the difference of employing motor type, also can be p-m rotor or other patterns; Speed changer has two axles, and left-hand axis is an input shaft among Fig. 1, connects wind energy conversion system and speed changer internal rotor, and right-hand axis is an output shaft, connects speed changer external rotor and generator; Second power inverter 4 and first power inverter 5 are received same DC electrical source, and this DC electrical source can be formations such as battery, electric capacity.

Sending out unit with a stylobate in the wind-force that electric stepless gear was constituted of induction machine is example, as shown in Figure 2, the internal rotor of speed changer directly links to each other with the wind-force arbor, internal rotor is installed on the input shaft, its surface embeds three-phase symmetric winding, links by slip ring and brush and first power inverter 5, and external rotor is installed on the hollow skeleton, hollow skeleton then through Bearing Installation on input shaft, output shaft links to each other with hollow skeleton.The inside and outside surface of external rotor embeds the cage modle winding respectively, embeds three-phase symmetric winding on the stator, and links with second power inverter 4, and output shaft directly links to each other with generator shaft, and main generator adopts three-phase synchronous generator.

The utility model adopts electric stepless gear to replace the mechanical speed-increasing gear-box, can realize stepless change on the one hand, make the generator constant-speed operation, on the other hand, because the electrical variable speed device has two power circuits, unnecessary wind energy can be stored in the energy-storage travelling wave tubes such as electric capacity or battery, discharge the deficiency of replenishing wind energy where necessary again, thereby can obviously improve the utilization ratio of wind energy.

Claims

1. an electric stepless speed change double power flow wind power generating set is characterized in that this generator set comprises wind energy conversion system (1), electric stepless gear (2), generator (3), second power inverter (4), (5) five parts of first power inverter; Wherein electric stepless gear (2) comprises stator (2.1), external rotor (2.2), internal rotor (2.3) and slip ring (2.4); Wind energy conversion system (1) connects internal rotor (2.3) by input shaft (6), is provided with slip ring (2.4) on input shaft (6); Periphery at internal rotor (2.3) is provided with external rotor (2.2), is provided with stator (2.1) in the periphery of external rotor (2.2); External rotor (2.2) connects with generator (3) by output shaft (7); Internal rotor (2.3) is gone up and is placed polyphase windings, is connected to first power inverter (5) through slip ring (2.4) and brush; Stator is also placed polyphase windings on (2.1), and links to each other with second power inverter (4); Second power inverter (4) and first power inverter (5) are received same DC electrical source.

2. the two power wind power generating set of electric stepless speed change according to claim 1, the power that it is characterized in that wind energy conversion system (1) input is divided into mechanical output and two passages of electric power are delivered to output terminal, promptly so-called double power flow.

3. electric stepless speed change double power flow wind power generating set according to claim 1 is characterized in that the difference of external rotor (2.2) structure according to the employing motor type, can be cage-type rotor, also can be p-m rotor.

4. electric stepless speed change double power flow wind power generating set according to claim 1, it is characterized in that the external rotor (2.2) of electric stepless gear (2), the inboard that internal rotor (2.3) both can be placed on stator (2.1), also can be placed on stator (2.1) outside, can also respectively put one in the medial and lateral of stator (2.1).