RU174686U1 - THREE-PHASE MAGNETOELECTRIC GENERATOR - Google Patents

Abstract

The utility model relates to the field of electrical engineering, namely to low-speed three-phase electric generators, and can be used, in particular, in wind power plants. In a three-phase magnetoelectric generator, which includes three independent modules, each of which contains a rotor mounted on the shaft, on the outer surface of which permanent magnets of alternating polarity are equidistantly installed, and a stator made in the form of an annular magnetic circuit with radially spaced teeth with windings, Rich stators are rotated relative to each other by a third period of the sinusoidal current, according to the utility model the distance between the stator teeth is twice the width of the teeth, and the rotor permanent magnet in the circumferential length equal to the distance between the stator teeth. The ring-shaped magnetic circuit can be made of lined from thin ring-shaped plates or of a composite ferromagnetic material. Due to the equality of the number of magnets and windings, all windings are simultaneously involved in the induction of EMF, as a result of which high efficiency is maintained. The same force of magnetic attraction between the magnets and the ferromagnetic material of the stator teeth is always ensured. at any angle of rotation of the rotor relative to the stator, two teeth are located in the area of magnet attraction over the area, which eliminates the effect of “sticking of the rotor”.

Description

The utility model relates to the field of electrical engineering, namely to low-speed three-phase electric generators, and can be used, in particular, in wind power plants.

A low-speed three-phase magnetoelectric generator is known, comprising a stator with an annular magnetic circuit with radially spaced teeth with windings and a disk rotor with permanent magnets with axial magnetization and alternating polarity mounted on the shaft, and each tooth has a magnet equal in area to it (Calculation of parameters of a low-speed 196-pole electric generator with a rotor with a diameter of 1 meter with permanent magnets, “Laboratory of Independent Research (website of I.A. Mukhin)”, 09/03/2007 (http: //imlab.narod. com / Energy / Gen_196 / Gen_196.htm) (copy attached)).

When the permanent magnets coincide with the teeth of the stator magnetic circuit (Fig. 5.1) due to the attractive forces, a large moment of resistance to rotation of the rotor with the shaft appears (“sticking of the rotor”). To overcome the "sticking of the rotor" it is necessary to significantly increase the starting torque on the generator shaft.

A three-phase synchronous motor is known, containing a stator with the number of slots Z = 3K (where K = 1, 2, 3, ...), in which its winding coils are located, covering one stator tooth, and an active rotor with poles of alternating polarity, the number of which is 2p = 2K (where p = the number of pairs of poles); the rotor is made with the length of the pole arc corresponding to the central angle α = 120 ° / K, and in the phase of the stator windings are switched on in series or parallel to K of the windings offset from each other by three grooves; the ratio of the number of magnets to the number of windings is 2: 3 (BY 9044 C1, publ. 30.04.2007).

The sticking effect is somewhat smoothed out due to the inequality of the number of windings to the number of magnets. However, the efficiency of the generator is significantly reduced, because not all windings are simultaneously involved in the induction of electromotive force (EMF).

Known low-speed three-phase generator, which includes three independent modules, each of which contains a rotor mounted on the shaft, on the outer surface of which are equidistant permanent magnets of alternating polarity, and a stator made in the form of an annular magnetic circuit with radially spaced teeth with windings, and the stators are rotated relative to each other friend for a third of the period of the sinusoidal current, 120 °, (CN No. 2745268 Y, publ. 07.12.2005).

This generator is adopted as a prototype of this utility model.

The generator contains the same number of magnets and teeth with windings, which causes the effect of “sticking of the rotor”. Due to the fact that the stators are rotated relative to each other by a third of the period of the sinusoidal current, the total effect of "sticking" is reduced. The disadvantage of the prototype is the presence of the residual effect of “sticking of the rotor”, due to the absence of a decrease in the magnetic interaction of the ferromagnetic material of the tooth and magnets.

The objective of this utility model is to eliminate the effect of “sticking of the rotor” while maintaining high generator efficiency,

The problem is solved due to the fact that in a three-phase magnetoelectric generator, which includes three independent modules, each of which contains a rotor mounted on the shaft, on the outer surface of which permanent magnets of alternating polarity are equidistantly mounted, and a stator made in the form of an annular magnetic circuit with radially spaced teeth with windings, and the stators are rotated relative to each other by a third of the period of the sinusoidal current, according to a utility model, the distance between the teeth of the stat ra twice the width of the teeth, and a permanent magnet rotor circumferential length equal to the distance between the stator teeth.

The ring-shaped magnetic circuit can be made of lined from thin ring-shaped plates or of a composite ferromagnetic material.

Thanks to the implementation of the restrictive and distinctive features of the utility model, a new technical result is achieved:

a sharp decrease in the effect of “sticking of the rotor”: due to the distance between the stator teeth being twice the width of the tooth, and the length of the permanent magnet of the rotor in a circle equal to the distance between the stator teeth, the same force of magnetic attraction between the magnets and the ferromagnetic material of the stator teeth is provided, t. to. for any angle of rotation of the rotor relative to the stator in the magnet attraction zone, there is a total area from all teeth equal to the area of two teeth, which eliminates the effect of “sticking of the rotor”;

maintaining high generator efficiency: due to the equality of the number of magnets and windings, all windings are involved in the induction of EMF, which ensures high generator efficiency;

additional increase in generator efficiency: due to the implementation of the ring-shaped magnetic circuit burdened from thin ring-shaped plates from electrical steel or from composite ferromagnetic material, for example iron powders (http://pandia.ru/text/78/187/10536.php), losses are reduced by heating by eliminating the influence of Foucault currents, which further increases the efficiency of the generator.

The essence of the utility model is illustrated by drawings, which depict

in FIG. 1 - General view of the generator assembly with a partial breakout;

in FIG. 2 - assembly units of the generator of FIG. one;

in FIG. 3 is a side view of the structure of a separate module;

in FIG. 4 is a diagram showing a relative arrangement of stator teeth and magnets during rotor rotation.

Three-phase magnetoelectric generator includes three independent modules 1, 2, 3 (Fig. 1). Each module contains a rotor 4 mounted on the shaft (Fig. 2), on the outer surface of which permanent magnets 5 of alternating polarity are equidistantly mounted. Each rotor 4 has its own stator 6. Each stator 6 is made in the form of an annular magnetic core 7 with radially spaced teeth 8 with windings 9, and the stators 6 are rotated relative to each other by a third of the sinusoidal current period, i.e. 120 ° (Fig. 1). The distance "b" between the teeth 8 of the stator 6 is twice the width "a" of the tooth 8 (Fig. 3). The length "c" of the permanent magnet 5 of the rotor 4 around the circumference is equal to the distance "b" between the teeth 8 of the stator 6. The distance "d" between the permanent magnets 5 is equal to the width "a" of the tooth 8:

b = 2a, a = d, b = c.

The ring-shaped magnetic core 7 can be made of baked from thin ferromagnetic ring-shaped plates or from a composite ferromagnetic material made by powder metallurgy, for example, iron powders (http://pandia.ru/text/78/187/10536.php).

A three-phase magnetoelectric generator operates as follows. When the rotor 4 rotates, the magnets 5, passing over the teeth 8, cause a change in the magnetic field in the teeth 8, which, in turn, according to the law of electromagnetic induction, induces in the windings 9 located on the teeth 8, an EMF proportional to the rate of change of the magnetic flux. Since the magnets 5 of the rotor 4 have alternating polarity, as the rotor 4 rotates in each tooth 8, the direction of the magnetic field also changes to the opposite, and, consequently, the polarity of the EMF in the winding 9 also changes to the opposite, forming a section of a sinusoid of opposite polarity. Since the stators 6 of all three modules 1, 2, 3 are rotated relative to the axis of rotation of the rotor 4 by 120 electrical degrees of the full sine wave period, one of the three phases necessary for three-phase switching is formed on each of the stators 6. The windings 9 of all three phases are independent and can be switched on by a "star" or "triangle" depending on the need.

Since at any angle of rotation of the rotor 4 in the zone of the magnet 5 there are two teeth 8 in area (Fig. 4 (a, b, c), the "parasitic" force of attraction of the teeth 8 to the magnets 5 is constant, therefore there is no "sticking of the rotor". the fact that the number of teeth 8 and magnets 5 in each module 1, 2, 3 of the stator 6 is the same, a completely synchronous generation of EMF is provided, which means maximum efficiency.

The generator can also operate as an electric motor.

For the manufacture of a three-phase magnetoelectric generator, conventional structural materials and factory equipment were used. This circumstance, according to the applicant, allows us to conclude that this utility model meets the patentability condition “Industrial Applicability”.

Claims (3)

1. A three-phase magnetoelectric generator, including three independent modules, each of which contains a rotor mounted on the shaft, on the outer surface of which permanent magnets of alternating polarity are equidistantly mounted, and a stator made in the form of an annular magnetic circuit with radially spaced teeth with windings, and the stators are rotated relative to each other for a third of the period of the sinusoidal current, characterized in that the distance between the teeth of the stator is two times the width of the tooth, and the length of the stand of the rotor magnet around the circumference is equal to the distance between the stator teeth. 2. The generator according to claim 1, characterized in that the ring-shaped magnetic circuit consists of thin ring-shaped plates. 3. The generator according to claim 1, characterized in that the annular magnetic core is made of composite ferromagnetic material.

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