WO2010051691A1

WO2010051691A1 - Direct-drive permanent magnet synchronous small wind generator

Info

Publication number: WO2010051691A1
Application number: PCT/CN2009/070462
Authority: WO
Inventors: 徐继鸿; 吴金华; 赵少俊
Original assignee: 鹤山市鹤龙机电有限公司
Priority date: 2008-11-05
Filing date: 2009-02-18
Publication date: 2010-05-14

Abstract

A direct-drive permanent magnet synchronous small wind generator includes: a housing(1), a shaft(2) mounted in the housing(1) via bearings, the generator mounted with stators(7,8) and rotors(3,4) which have small number of slots and poles, each pole of the rotor (3,4) equipped correspondingly with a permanent magnet(5). The wind power generation system also includes an electric power storage device, a DC power supply adjusting control unit and a controller. The generator can keep the wind power generation system stable with the method of power adjustment and the energy compensation, and improve the efficiency of the power generation system.

Description

Small direct-drive permanent magnet synchronous wind generator and small wind power generation system thereof

[1] Technical field

[2] The present invention relates to a wind power generator and a wind power generation system, and more particularly to a small wind power generator and a wind power generation system thereof.

[3] Background Art

[4] Wind power is one of the fastest growing technologies in renewable energy. Commonly used are AC asynchronous generators and doubly-fed asynchronous generators. In wind power systems, gears are required to increase speed. For doubly-fed asynchronous generators, carbon is required. Brushes and slip rings, which are costly to manufacture, have low reliability, and are very noisy.

[5] No gearbox, direct drive, and brushless have attracted people's attention. The new wind power system solution is variable speed operation, variable pitch adjustment, low speed, high efficiency, high power factor direct drive multi-pole permanent magnet synchronization. Generators have become a hot spot in current research and development.

[6] Among them, the small wind power generation system is not suitable for the variable pitch adjustment mechanism because of its small size and low unit price. Therefore, the prior art generally adopts a fixed pitch mode. However, due to the ever-changing wind speed, existing small-scale wind power generation systems are not suitable, and their work is unstable, unreliable, and low in wind energy utilization.

[7] In addition, the current multi-slot multi-pole motor for wind turbines has a corresponding number of stator slots. To meet the process requirements, the stator and rotor dimensions must be made large to obtain the required frequency. Due to the large moment of inertia, potential fluctuations due to wind changes can be suppressed. However, the multi-groove multi-pole structure is complicated in structure and unstable in performance, so that the best use effect cannot be achieved, and the motor has the disadvantages of large volume and high cost, and the same needs for the use of a reduction box. Therefore, the cost of the small wind turbine cannot be further reduced. Traditionally, there are technical prejudices. It is believed that the relatively simple structure of the small-slot and low-pole structure causes the problems of excessive radial electromagnetic force, severe vibration and high noise, and has been used only in small or micro-generators. Low-speed, high-torque generators are often used in relatively complex multi-slot multi-pole configurations, while relatively simple structures with less slots and fewer poles are not used and attempted in low-speed, high-torque generators.

[8] In addition, in the patent document with the publication number CN101017998A and the publication date of August 15, 2007 A direct-drive excitation wind turbine with a double stator structure is adopted, which realizes the power density through the double stator structure and captures the maximum wind energy. Although a certain use effect is achieved, the fan using the structure only The power density can be simply increased, the operation is unstable under a wide range of wind speeds, and the manufacturing cost is too high when the power density is simply increased.

Summary of the invention

The technical problem to be solved by the present invention is to provide a small direct-drive permanent magnet synchronous wind power generator with simple structure, high efficiency and stable operation, and to provide a simple structure, low cost, reliable use, high utilization rate of wind energy, and operation. Smooth small wind power system. .

In order to solve the above technical problem, a small direct-drive permanent magnet synchronous wind power generator of the present invention includes a casing, and the casing is mounted with a rotating shaft through a bearing, the generator has a stator and a rotor with a small groove and a small pole structure, and a corresponding rotor Each pole is provided with a permanent magnet.

The stator has a 9-slot structure, and the rotor is provided with 8 or 10 poles. The permanent magnets are magnetic steel and are disposed on each pole of the rotor.

As an improvement of the above technical solution, a main motor and an auxiliary motor having the stator and the rotor are disposed in a casing of the generator, and the stator is divided into a main motor stator and an auxiliary motor stator, a main motor stator and an auxiliary motor stator. The main motor stator winding and the auxiliary motor stator winding are respectively arranged, and one set of windings in the auxiliary motor stator winding is connected with a DC power supply regulation control end.

A small wind power generation system, comprising a wind turbine, a generator and an electric energy storage, the wind turbine is directly connected with a generator, the generator is a direct drive permanent magnet synchronous generator, and the generator has a stator with a small groove and a small pole structure And the rotor, each pole of the corresponding rotor is provided with a permanent magnet.

A main motor and an auxiliary motor having the stator and the rotor are disposed in a casing of the generator, and the stator is divided into a main motor stator and an auxiliary motor stator, and a main motor stator is respectively disposed on the main motor stator and the auxiliary motor stator Winding and auxiliary motor stator windings, main motor stator windings and auxiliary motor stator winding output terminals are connected to electrical energy storage and electrical equipment through cables, auxiliary motor stator windings are connected with DC power supply regulator, DC power supply regulator connection controller The input end of the controller is connected to the wind turbine to perform speed detection on the wind turbine. [17] The beneficial effects of the present invention are: Due to the above structure, the small direct-drive permanent magnet synchronous wind power generator can realize low-speed and high-torque input, has high power density, can cancel the gear transmission mechanism, and reduces The overall volume of the wind power generation system can avoid the failure of the gear transmission mechanism, improve the working efficiency of the entire power generation system, and the generator of the power generation system can operate stably over a wide wind speed range, and utilize wind energy more efficiently. The process is simple. Moreover, the motor includes a main motor and an auxiliary motor, a double stator and a double rotor structure, and the power regulation and energy compensation can be used to maintain the stability of the wind power generation system, and the torque adjustment by the auxiliary motor realizes the torque damping speed adjustment. Maintain constant speed, power compensation in case of insufficient wind power, run at rated speed, main motor directly supplies power to generator, auxiliary motor idles, the working efficiency of the whole power generation system can be effectively improved, and the generator of power generation system can be compared Stable operation over a wide range of wind speeds, more efficient use of wind energy, and simple operation. Further, the stator and the rotor are small-slot and low-pole structures to achieve low-speed and high-torque input, have high power density, can cancel the gear transmission mechanism, reduce the overall volume of the wind power generation system, and avoid gear transmission. Institutional wear and tear causes failures, improves the efficiency of the entire power generation system, and its cost can be greatly effectively reduced, which has great economic benefits.

[18] BRIEF DESCRIPTION OF THE DRAWINGS

[19] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

1 is a cross-sectional view showing the internal structure of a generator having a rotor of 8 poles according to the present invention;

Figure 2 is a cross-sectional view showing the internal structure of a generator having a 10-pole rotor according to the present invention;

[22] FIG. 3 is a schematic structural view of a generator of the present invention;

[23] FIG. 4 is another schematic structural view of the generator of the present invention;

Fig. 5 is a schematic structural view of a power generation system of the present invention.

[25] Specific implementation

Referring to FIG. 1 and FIG. 2, a small direct-drive permanent magnet synchronous wind power generator of the present invention comprises a casing 1 , and a casing 1 is mounted with a rotating shaft 2 through a bearing, and the generator has a small groove and a small pole structure. The stator and the rotor are provided with permanent magnets 5, 6 corresponding to each pole of the rotor. The stator and rotor of the motor are simple in structure, and the number of poles and the number of slots are optimally matched, and the pole has a very high power density. Specifically, the stator is a 9-slot structure, and the rotor is provided with 8 poles or 10 poles. It is magnetic steel and is placed on each pole of the rotor.

[27] a main motor and an auxiliary motor having the stator and the rotor are provided in a casing of the generator, and the stator The main motor stator 7 and the auxiliary motor stator 8, the main motor stator 7 and the auxiliary motor stator 8 are respectively provided with a main motor stator winding 9 and an auxiliary motor stator winding 10, and a set of windings in the auxiliary motor stator winding 10 are connected with a direct current. Power supply regulation control terminal.

Referring to FIG. 3, as an embodiment of the above technical solution, the rotor is a main motor rotor 3 and an auxiliary motor rotor 4, and the main motor rotor 3 and the auxiliary motor rotor 4 are respectively coupled to the main motor stator 7 and The auxiliary motor stator 8 is correspondingly arranged.

Referring to FIG. 4, as another embodiment of the above technical solution, the main motor stator 7 is sleeved on the periphery of the auxiliary motor stator 8, and the rotor is disposed between the main motor stator 7 and the auxiliary motor stator 8. The permanent magnets are disposed on the outer and inner sides of the rotor corresponding to the main motor stator 7 and the auxiliary motor stator ₈ , respectively.

[30] The magnetic steel is rectangular, embedded in the rotor, and arranged in a tangential direction. The slots of the stator are straight grooves, and the grooves are the same and evenly distributed.

[31] The main motor stator winding and the auxiliary motor stator winding are three-phase, three-phase three-group winding 120° concentrated embedded

[32] Referring to FIG. 5, a small wind power generation system of the present invention includes a wind turbine, a generator and an electric energy storage, the wind turbine is directly connected to a generator, and the generator is a direct drive permanent magnet synchronous generator, The generator has a stator and a rotor with a small groove and a small pole structure, and permanent magnets 5, 6 are provided for each pole of the corresponding rotor. The stator is a 9-slot structure, and the rotor is provided with 8 or 10 poles. The permanent magnets are magnetic steel and are disposed on each pole of the rotor.

[33] As an embodiment of the above technical solution, a main motor and an auxiliary motor having the stator and the rotor are disposed in a casing of the generator, and the stator is divided into a main motor stator 7 and an auxiliary motor stator 8 The main motor stator 7 and the auxiliary motor stator 8 are respectively provided with a main motor stator winding 9 and an auxiliary motor stator 10 winding, and the output ends of the main motor stator winding 9 and the auxiliary motor stator winding 10 are connected to the electric energy storage device and the electric equipment through a cable. The auxiliary motor stator winding 10 is connected with a DC power supply regulator, the DC power supply regulator is connected to the controller, and the input end of the controller is connected to the wind turbine to perform speed detection on the wind turbine.

[34] As another embodiment of the above technical solution, the rotor is a main motor rotor 3 and an auxiliary motor rotor 4, and the main motor rotor 3 and the auxiliary motor rotor 4 are respectively coupled to the main motor stator 7 and the auxiliary motor stator. 8 corresponds to the setting.

[35] The main motor stator 7 is sleeved on the periphery of the auxiliary motor stator 8, and the rotor is disposed on the main motor stator 7 Between the stator 8 and the auxiliary motor stator, the permanent magnets are disposed on the outer and inner sides of the rotor corresponding to the main motor stator 7 and the auxiliary machine stator 8, respectively.

[36] The magnetic steel is rectangular, embedded in the rotor, and arranged in a tangential direction. The slots of the stator are straight grooves, and the grooves are the same and evenly distributed. Preferably, the stator windings are three-phase, three-phase three-group windings 120. Concentrated embedded.

[37] Further, the generator belongs to a small-slot and low-pole structure, which is a high-density magnetic circuit. The stator winding turns multi-pole permanent magnet synchronous generator is ten times more than the multi-pole permanent-magnet synchronous generator, making full use of the slot space to increase the winding turns to obtain The low back-speed operation produces a high back-EM voltage. Under low-speed conditions, it can directly output 220V. The system is designed for constant speed, constant frequency, fixed pitch, dual-stator dual-rotor structure, control mode, power regulation and energy. The method of compensation keeps the system stable, so the present invention is a novel wind power generation system.

[38] 双Using a double motor structure, when the wind speed is appropriate, at the rated speed, the main motor is directly powered by the generator, and the auxiliary motor is idling;

[39] When the wind speed is large, run 在 above the rated speed, DC is supplied to one of the auxiliary motor stator windings. The current is determined by the fan speed feedback. The current and torque relationship curve is the test curve measured by the auxiliary motor. The operation is torque damping speed adjustment;

[40] When the wind speed is small, running below the rated speed, the auxiliary motor is put into power generation operation, and its electric energy is connected to the cable of the main motor. This operation is power adjustment compensation.

[41] The following is a further description of an embodiment of the generator of the present invention:

[42] Technical parameters of small direct drive permanent magnet wind turbines,

[43] 1. Rated power P=5000W

[44] 2. Rated wind speed VW=9m/s

[45] 3. Ratio of tip speed to wind speed λ=7.94

[46] 4. Wind energy utilization coefficient ω=0.294

[47] 5, blade radius Y = 3.5m diameter = 7m

[48] 6, rated number of revolutions of wind turbines n=295r/min

[49] 7, tower height H = 10m

[50] 8, output voltage three-phase 220V

[51] The control scheme is as follows:

[52] 1, constant speed, constant frequency, rated speed 195r / min, frequency 13HZ, frequency variation error ± 20%; [53] 2. When the wind speed VW exceeds 10.8m/s吋, the auxiliary generator is started, and one of the winding wires is supplied with DC current. For the speed feedback, the current is determined by the analysis, and the damping torque is generated to keep the wind turbine speed not maintained. change.

[54] 3. When the wind speed VW is lower than 7.2m/s吋, start the auxiliary generator power generation function to supplement the power supply to the grid. Because the characteristics of the main motor and the auxiliary motor are the same, no intermediate control is needed.

[55] 4. When the wind speed is too high, stop supplying power.

In addition, the generator of the present invention and its system use 吋, and the power device with frequency requirement can increase the power supply frequency by the frequency predetermined device, and can be directly used for power without the requirement of frequency.

[57] In addition, the starting resistance torque is caused by the cogging effect. In the test of the present invention, the influence is extremely small, and the rotating stator does not need a chute, and the winding turns are several times higher than the multi-pole generator, and The back-emistence voltage is also very high. The current through the wire is smaller than that of the multi-pole motor. The current is the main factor of heat generation. The current is small and the heat is there. The generator is a low-frequency generator, and the motor has little iron loss. Therefore, it does not generate heat, and the physical properties of the magnetic steel can be prevented from being affected and affected.

[58] In terms of control technology, wind speed has random volatility, resulting in large and small wind energy utilization. Therefore, there must be a control method to maximize wind energy capture by controlling the same quality of power. The wind power system of the present invention has Higher efficiency.

[59] In terms of economy, the generator has a simple structure and low manufacturing cost. Because there is no gearbox and blade torque converter, the operational reliability is improved and maintenance is not required during the design life.

[60] The system can be applied to decentralized power supply, independent power supply, small-scale water utilization of farmland, and reduced engineering investment in centralized power supply. The unit cost of small wind power generation system is lower than that of centralized power supply.

[61] Due to the use of the generators of the above-mentioned stator and rotor, power conditioning and energy compensation can be used to maintain the stability of the wind power generation system, torque adjustment by the auxiliary motor, constant speed, and insufficient wind power. Power generation for power compensation, running at rated speed, the main motor is directly powered by the generator, the auxiliary motor is idling, the working efficiency of the whole power generation system can be effectively improved, and the generator of the power generation system can stably operate in a wide wind speed range, more efficient The use of wind energy in the ground, the operation process is simple.

Claims

Claim

[1] A small direct-drive permanent magnet synchronous wind turbine, comprising a casing, the casing being mounted with a shaft through a bearing

The generator is characterized in that the generator has a stator and a rotor having a small groove and a small pole structure, and a permanent magnet is provided for each pole of the corresponding rotor.

[2] The miniature direct-drive permanent magnet synchronous wind power generator according to claim 1, wherein the stator is a 9-slot structure, the rotor is provided with 8 poles or 10 poles, and the permanent magnet is a magnetic steel Set on each pole of the rotor.

[3] The miniature direct-drive permanent magnet synchronous wind power generator according to claim 1 or 2, wherein a main motor and an auxiliary motor having the stator and the rotor are disposed in a casing of the generator, The stator is divided into a main motor stator and an auxiliary motor stator. The main motor stator and the auxiliary motor stator are respectively provided with a main motor stator winding and an auxiliary motor stator winding, and a set of windings in the auxiliary motor stator winding are connected with a DC power supply regulation control end.

[4] The miniature direct-drive permanent magnet synchronous wind power generator according to claim 3, wherein the rotor is a main motor rotor and an auxiliary motor rotor distributed front and rear, and the main motor rotor and the auxiliary motor rotor are respectively coupled to the main motor stator Corresponding to the auxiliary motor stator.

[5] The miniature direct drive permanent magnet synchronous wind power generator according to claim 3, wherein the main motor stator is sleeved on a periphery of the auxiliary motor stator, and the rotor is disposed between the main motor stator and the auxiliary motor stator. The permanent magnets are disposed on the outer and inner sides of the rotor corresponding to the main motor stator and the auxiliary motor stator respectively.

[6] The small direct-drive permanent magnet synchronous wind power generator according to claim 2, wherein the magnetic steel is rectangular, embedded in the rotor, and arranged in a tangential direction, and the slot of the stator is a straight groove, a slot The shape is the same, evenly distributed.

[7] The miniature direct-drive permanent magnet synchronous wind power generator according to claim 3, wherein the stator windings of the main motor and the stator windings of the auxiliary motor are three-phase, and the three-phase three-group windings are 120° concentrated.

[8] A small wind power generation system comprising a wind turbine, a generator and an electrical energy storage, the wind turbine being directly connected to the generator, characterized in that the generator is a direct drive permanent magnet synchronous generator, and the generator has less The stator and the rotor of the slot-and-pole structure are provided with permanent magnets corresponding to each pole of the rotor.

[9] The small-scale wind power generation system according to claim 8, wherein the stator is a 9-slot structure The rotor is provided with 8 poles or 10 poles, and the permanent magnets are magnetic steel and are disposed on each pole of the rotor.

[10] The small-scale wind power generation system according to claim 8 or 9, wherein a main motor and an auxiliary motor having the stator and the rotor are provided in a casing of the generator, and the stator is divided into a main motor The stator and the auxiliary motor stator, the main motor stator and the auxiliary motor stator are respectively provided with a main motor stator winding and an auxiliary motor stator winding, and an output end of the main motor stator winding and the auxiliary motor stator winding is connected to the electric energy storage device and the electric equipment through a cable. The auxiliary motor stator winding is connected with a DC power supply regulator, the DC power supply regulator is connected to the controller, and the input end of the controller is connected to the wind turbine to perform speed detection on the wind turbine.

[11] The small-scale wind power generation system according to claim 10, wherein the rotor is a main motor rotor and an auxiliary motor rotor distributed front and rear, and the main motor rotor and the auxiliary motor rotor respectively correspond to the main motor stator and the auxiliary motor stator Settings.

[12] The small-scale wind power generation system according to claim 10, wherein the main motor stator is sleeved on a periphery of the auxiliary motor stator, and the rotor is disposed between the main motor stator and the auxiliary motor stator, the permanent magnet It is disposed on the outer and inner sides of the rotor corresponding to the main motor stator and the auxiliary machine stator respectively.