WO2009132479A1

WO2009132479A1 - A dual-layer rotor wind mill generator

Info

Publication number: WO2009132479A1
Application number: PCT/CN2008/000976
Authority: WO
Inventors: 曹江
Original assignee: 许军; 刘宏; 刘沛棋
Priority date: 2008-04-28
Filing date: 2008-05-20
Publication date: 2009-11-05
Also published as: CN201207588Y

Abstract

A dual-layer rotor wind mill generator includes a crankshaft (5), a rotor (1) fixed to the crankshaft (5) and a stator (3) installed surround the crankshaft (5). The rotor (1) comprises an inner layer (12) and an outer layer (14) which are molded integrally. The inner layer (12) and the outer layer (14) form U-shape slot, and outer layer magnetic plates (20) and inner layer magnetic plates (40) are located on the inner wall of the U-shape slot. The outer layer magnetic plates (20) and the inner layer magnetic plates (40) mount in pairs and their polarities are opposite. Coils (30) fixed to the stator (3) are sandwiched between the outer layer magnetic plates (20) and the inner layer magnetic plates (40) in the U-shape slot.

Description

Double-layer rotor wind turbine

The present invention relates to a wind power generator, and more particularly to a novel double layer rotor structure for a wind power generator. Background technique

A conventional wind turbine is usually composed of a set of rotors and a set of stators. The rotor rotates under the force of the wind, and the coil cuts the magnetic lines of force to generate electric current. The magnetic field generated by this single-layer rotor magnet structure consists of a number of similarly distributed circular lines of magnetic force. When the coil moves in such a magnetic field, its efficiency is relatively low.

Summary of the invention

The technical problem to be solved by the present invention is to improve the structure of the rotor of the generator and optimize the magnetic field distribution on the trajectory of the coil to greatly increase the magnetic flux passing through the coil, thereby improving the efficiency of the generator.

In order to solve the above technical problem, the technical solution adopted by the present invention is a two-layer rotor wind power generator comprising a crankshaft, a rotor fixed on the crankshaft, a stator mounted around the crankshaft, the rotor including an integrally formed outer layer And an inner layer, the outer layer and the inner layer constitute a u-shaped groove, and an outer layer magnetic piece and an inner layer magnetic piece are respectively mounted on the inner wall surface of the U-shaped groove, and the outer layer magnetic piece and the inner layer magnetic piece are matched in pairs and The polarity is reversed; the coil fixed to the stator is sandwiched between the outer magnetic sheet and the inner magnetic sheet in the u-shaped groove.

Wherein, the outer layer of the rotor and the inner layer of the rotor are provided with uniformly distributed protrusions.

Wherein, the outer and outer magnetic sheets mounted on the outer layer of the rotor and the inner layer of the rotor have the same opening angle with respect to the center of the crankshaft. Wherein, the same number of outer magnetic sheets and inner magnetic sheets are uniformly distributed in a ring shape around the generator shaft.

Wherein, the radial spacing of the paired outer layer magnetic sheet and the inner layer magnetic sheet is the smallest in the middle of the magnetic sheet, and the closer to the lateral sides of the magnetic sheet, the larger.

Wherein, the edge of the radial section of the outer magnetic sheet facing the inner layer magnetic sheet is a part of an elliptical polarization deformation.

Wherein, the edge of the radial section of the inner layer magnetic sheet facing the outer layer of the magnetic sheet is a part of an ellipse.

Wherein, the edge of the radial section of the inner layer magnetic sheet facing the outer layer of the magnetic sheet is a part of an elliptical polarization.

Wherein, the edge of the radial section of the outer magnetic sheet facing the inner layer magnetic sheet is a part of an elliptical polarization deformation, and the radial section of the inner layer magnetic sheet faces the outer layer of the magnetic sheet. The edge is part of another elliptical polarization that is proportional to the length of their respective axes to the axis of the generator shaft.

Wherein, the eccentricity of the two ellipse is the same.

By comparing Fig. 1 and Fig. 2, the difference in the magnetic fields generated by the two rotor structures can be clearly seen. In Fig. 2, although the magnetic field on the outer side of the inner and outer magnetic sheets is similar to the magnetic field of the single-layer rotor, the magnetic field between the inner and outer layers, that is, the partial magnetic field actually passed by the coil, the magnetic field lines are substantially the same as the coil The trajectory of the movement is vertical. Due to the use of a paired inner and outer magnetic plate structure, the magnetic flux is significantly larger in the magnetic field than in the magnetic field of Fig. 1 when the coil is moved in such a magnetic field. The beneficial effects of the present invention are positive It is based on the optimization of the magnetic field brought about by the double-layer rotor structure, which can effectively improve the power generation efficiency of the wind power generator.

DRAWINGS

Figure 1 is a schematic diagram showing the magnetic field lines of a single-layer rotor.

Figure 2 is a schematic diagram showing the magnetic field lines of the double-layer rotor.

3 is a schematic view showing the internal structure of the double-layer rotor wind power generator of the present invention.

Figure 4 is a cross-sectional view taken along line A-A of Figure 3;

Fig. 5 is a schematic view showing the relationship between the dimensions of the inner and outer magnetic sheets.

Figure 6 is a schematic diagram of the spacing between the inner and outer magnetic sheets.

Fig. 7 is a view showing a situation in which the pitches of the inner and outer magnetic sheets are inconsistent.

Fig. 8 is a schematic view showing the distribution of magnetic field strength between the inner and outer magnetic sheets on the relative movement trajectory of the coil. Figure 9 is a schematic view showing the internal structure of a generator using unequal inner and outer magnetic sheets.

Fig. 10 is a schematic view showing the curved bending deformation of the curve.

Fig. 11 is a schematic view showing the curve L of the outer bend polarization.

Figures 12, 13 and 14 are three embodiments of improved magnetic disk spacing.

In the figure: 1. rotor; 12. outer layer of rotor; 14. inner layer of rotor; 20. outer magnetic sheet; 40. inner layer magnetic sheet; 3. stator; 30. coil; 5. crankshaft; A protrusion on the layer.

The symbols in the figure mean: Θ is the opening angle of the inner and outer magnetic sheets with respect to the axis of the crankshaft; d0, dl, d2 are the radial distances between different positions of the inner and outer magnetic sheets; P (a, b) is in the plane Any point on the curve L in the coordinate system (x, y); P' (a, ω ) is the point on the curve L' in the polar coordinate system, which exists with the point Ρ Corresponding relationship before and after polarization deformation; point 0 is the center of the crankshaft.

detailed description

Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

In Fig. 3, the rotor 1 is coupled to the crankshaft of the generator, and the rotor 1 includes an annular two-layer structure spaced apart from each other: a rotor outer layer 12 and a rotor inner layer 14, which form a concave U-shaped ring groove. An outer magnetic sheet 20 and an inner magnetic sheet 40 are attached to the surfaces facing each other. The coil 30 fixed to the stator 3 is sandwiched in the recessed ring groove; a certain gap is left between the coil 30 and the inner and outer magnetic sheets on the rotor to ensure free rotation of the rotor. The stator 3 is fixedly connected to the casing, and the casing is omitted in FIG.

When the rotor is rotated by the blades connected to the crankshaft 5, the coil 30 is moved relative to the magnetic field between the inner and outer magnetic sheets. The coil cuts the magnetic lines of force to generate a current.

Figure 4 is a cross-sectional view showing the internal structure of the generator in the A-A direction perpendicular to the crankshaft. The rotor outer layer 12 and the outer layer magnetic sheet 20 constitute a large ring of the outer layer; the inner rotor layer 14 and the inner layer magnetic sheet 40 constitute a small ring of the inner layer; and the coil 30 is sandwiched between the inner and outer rings.

In order to facilitate the uniform distribution of the magnetic sheets on the rotor, the projections 11 are evenly distributed on the outer layer 12 of the rotor. Similarly, a similar structure can be found on the inner layer of the rotor.

Figure 5 shows the optimized inner and outer magnetic plate size ratios. With respect to the axis of the crankshaft 5, the outer magnetic sheet 20 and the inner magnetic sheet 40 have the same opening angle Θ, that is, their respective arc lengths along the circumference are proportional to their distance from the axis.

Figure 12 shows an embodiment in which the inner and outer magnet pieces are improved in pitch, wherein the inner side of the outer magnetic sheet 20 The surface is a plane, as a radial section, a straight line is shown in the figure; and the outer surface of the inner layer magnet 40 is a curved surface, and a curve is shown in the figure, which is centered on the center of the crankshaft 5. The arc.

Figure 13 is a further improvement on the basis of Figure 12. A small arc treatment is performed on both ends of the outer surface of the inner layer magnetic sheet 40 so that the two edges are farther from the relative movement trajectory of the coil.

Figure 14 is another modified embodiment. The inner surface of the outer magnetic sheet 20 is a curved surface, and a curve is shown in the figure, which is an arc centered on the center of the crankshaft 5; and the outer surface of the inner magnetic sheet 40 is also a curved surface. Shown in the other curve, this curve is not an arc centered on the center of the crankshaft 5, it is part of an elliptical arc.

By adjusting the axial length and eccentricity of the ellipse, the spacing between the two magnetic sheets can be adjusted. As an optimized structure, the circumferential width of the inner and outer magnetic sheets of the double-layered rotor is proportional to the distance from the magnet to the generator shaft, or is close to proportional. Or the opening and closing angles of the inner and outer magnetic sheets with respect to the axis of the crankshaft are nearly the same. In Fig. 5, with respect to the axis of the crankshaft 5, the outer magnetic sheet 20 and the inner magnetic sheet 40 have the same opening angle Θ, that is, their respective arc lengths along the circumference and their distance from the axis In direct proportion. .

Further, by improving the distance distribution relationship between the inner and outer magnetic sheets on the rotor of the generator, the magnetic field intensity distribution on the trajectory of the coil can be optimized to obtain a current output closer to the sinusoid. The specific improvement features are: The radial distance between each pair of inner and outer magnet pieces on the double-layer rotor of the wind power generator is larger at the position closer to both sides of the magnetic sheet.

Figures 3 and 4 show the internal mechanism of a two-layer rotor wind turbine; Figure 2 shows this The magnetic field between the magnetic sheets on the double-layered rotor shows that the change in the magnetic field strength from the center of the magnetic sheet to the two sides does not form a desired gradient. This is because the center of each pair of magnetic sheets is not caused by the difference in the radial distance between the two sides, and this situation is more clearly shown in Fig. 6, in which the respective positions between the outer magnetic sheet 20 and the inner magnetic sheet 40 are The radial distance centered on the crankshaft 5 has the following relationship

D0 = dl = d2

Fig. 7 shows a modification in which the radial distance between the outer magnetic sheet 20 and the inner magnetic sheet 40 at the respective positions with respect to the crankshaft 5 has the following relationship.

D0 ^ dl ^ d2, d0 > d2

Figure 8 shows the improved magnetic field strength distribution. The circular dotted line in the figure represents the relative motion trajectory of the coil. Comparing Figure 2, we can see that the density of the magnetic lines of force, that is, the strength of the magnetic field, has a significant gradient change in the relative motion trajectory along the coil: the strength of the magnetic field near the center of the disk is strengthened, two adjacent The small magnetic field lines at the edges of the layered magnetic sheets are further away from the relative motion trajectories of the coils, as are the small magnetic field lines at the edges of the adjacent two inner magnetic sheets.

Figure 9 shows the internal structure of the generator with improved disk spacing.

There are many ways to achieve different spacing between the various positions of the magnetic sheets. A combination of a circular arc shape, a planar shape, and an elliptical surface is introduced in the following embodiments.

Further optimization requires a curve function to describe the cross-sectional shape of the magnetic sheet.

The curve L in the plane coordinate system (X, y) of the upper half of Fig. 10 is half of the left side of the long axis V of the ellipse, and the coordinate of the point P on L is (a, b).

When the coil is moved in a straight line, the curve L here is an ideal cross-sectional shape of the magnet piece. However, the coil actually does the relative movement of the circumference. Therefore, it is necessary to perform polarization deformation processing on the curve L. The polarization deformation here is a deformation in which the center of the crankshaft of the generator is a circle and the distance between the long axis of the ellipse and the center of the crankshaft is a radius. The lower part of Fig. 10 shows the situation after the deformation, the center 0 is the center of the crankshaft, the long axis V of the ellipse is deformed into the arc V', the curve L is deformed into L', and the point P on the L corresponds to the point P (a, b) To the point P' (a, ω ) in the polar coordinate system, where _a is the distance from point P' to point 0, which is equal to a in point P (a, b); ω is the angle, satisfying the following relationship formula

ω = b / a

The curve L' is the optimized curve of the deformed inner bend. When the magnetic sheet is actually processed, it is not necessary to use the complete curve L'. It is possible to use only a part of the curve L', and the left and right sides of the z-axis can be symmetric. It is.

Figure 11 shows the corresponding situation before and after the same polarization deformation of the half of the long axis V of the ellipse. The curve L in the plane coordinate system (x, y) is transformed into L' in the polar coordinate system, and the point P (a, b) corresponds to the point P' (a, ω ), and their coordinate values still satisfy the relation

ω = b / a

For a specific outer magnetic sheet, the edge of the radial section facing the inner magnetic sheet is the curve L' in Fig. 10, or a part thereof; and for the inner magnetic sheet, its radial direction The side line of the section facing the outer magnetic sheet is the curve L' in Fig. 11, or a part thereof. Part of what is said here is that both sides are symmetric about the axis z.

Claims

Claim

A two-layer rotor wind turbine comprising a crankshaft (5), a rotor (1) fixed to the crankshaft (5), and a stator (3) mounted around the crankshaft (5), characterized in that: The rotor (1) includes an integrally formed outer layer (12) and an inner layer (14), and the outer layer (12) and the inner layer (14) constitute a ϋ-shaped groove; the outer wall surface of the U-shaped groove is respectively installed a layer magnetic sheet (20) and an inner layer magnetic sheet (40), the outer magnetic sheet (20) and the inner magnetic sheet (40) are matched in pairs and opposite in polarity; a coil fixed on the stator (3) (30) ) is sandwiched between the outer magnetic sheet (20) and the inner magnetic sheet (40) in the U-shaped groove.

The two-layer rotor wind power generator according to claim 1, characterized in that: the outer layer (12) of the rotor and the inner layer (14) of the rotor are provided with uniformly distributed protrusions (11).

3. A two-layer rotor phoenix generator according to claim 1, characterized by: an outer magnetic piece (20) and an inner layer mounted on the outer layer (12) of the rotor and the inner layer (14) of the rotor The magnetic piece (40) has the same opening angle with respect to the center of the crankshaft.

The double-layer rotor wind power generator according to claim 1, characterized in that: the same number of outer magnetic sheets (20) and inner magnetic sheets (40) are uniformly distributed in a ring shape around the generator shaft (5) status.

The double-layer rotor wind power generator according to any one of claims 1 to 4, characterized in that: the radial spacing of the paired outer layer magnetic piece (20) and the inner layer magnetic piece (40) The middle of the magnet is the smallest, and the closer to the lateral sides of the magnet, the larger.

The double-layer rotor wind power generator according to claim 5, wherein: the edge of the radially outer section of the outer magnetic piece (20) facing the inner magnetic piece is an elliptical polarization deformation a part of.

7. A two-layer rotor wind power generator according to claim 5, wherein: said inner layer The edge of the radial section of the magnet piece (40) facing the outer disk piece (20)' is an elliptical portion.

The double-layer rotor wind power generator according to claim 5, wherein: the edge of the radial section of the inner layer magnetic sheet (40) facing the outer layer magnetic sheet (20) is an elliptical pole Part of the deformation.

The double-layer rotor wind power generator according to claim 5, wherein: the edge of the radially outer section of the outer magnetic piece (20) facing the inner magnetic piece (40) is an elliptical pole After the deformation, a portion of the radial section of the inner magnetic sheet (40) facing the outer magnetic sheet (20) is a part of another elliptical polarization deformation, and the long axes of the two ellipse The lengths are proportional to their respective distances from the axis of the generator shaft.

10. A two-layer rotor wind turbine according to claim 9, wherein: said two ellipse have the same eccentricity.