WO2022035355A1

WO2022035355A1 - Single-phase alternator

Info

Publication number: WO2022035355A1
Application number: PCT/RU2021/050218
Authority: WO
Inventors: Леонид Борисович ЛИСТКОВ
Original assignee: Леонид Борисович ЛИСТКОВ
Priority date: 2020-08-10
Filing date: 2021-07-16
Publication date: 2022-02-17
Also published as: RU2742393C1

Abstract

The invention relates to electrical engineering. The technical result is an increase in efficiency. The claimed single-phase alternator comprises an annular stator with ring windings, a rotor being arranged in the internal cavity of said stator, with magnets being mounted on the shaft of said rotor in such a manner that the radial magnetic orientation of the poles alternates. Moreover, the alternator comprises at least four identical screens that are arcuate in plan view, are rigidly mounted on the stator in pairs so as to fit tightly against said stator on either side thereof in the gaps between the ring windings of the stator, which are arranged evenly spaced around the circumference of the stator and are connected in antiparallel. The stator has at least four internal teeth, between which at least two ring windings are arranged evenly spaced around the circumference. The surface area of each screen is greater than the area of the surface thereof that makes contact with the stator.

Description

Single phase alternator

The invention relates to electrical engineering, namely to means for converting mechanical energy into AC electrical energy and can be used in mechanical engineering to create alternating current generators using a rotating magnetic field.

The main problem in creating alternators is their low efficiency, as well as the complexity of their designs.

So the generator of electric energy is known according to the patent of the Russian Federation for IM No. 195975, H02K 1/12, which includes a shaft installed with the possibility of rotation, basic and corrective inductors located coaxially and fixedly fixed on the shaft, as well as coaxially located basic and corrective anchors, each of which has an annular magnetic circuit with annular winding coils, which transversely cover the magnetic circuit of the base armature, while the winding coils of the corrective armature are made annular.

The disadvantages of the named electric power generator are the complexity of its design, as well as the low efficiency of this generator, due to the guidance of the base stator by the annular windings, under the influence of the load, the counter-torque, directed in the opposite direction of the rotation of the salient-pole base inductor.

Closest to the claimed invention is a single-phase alternator with an annular stator winding (patent for IZ RF No. 2513986, H02K 21/16), which is selected as a prototype. This generator contains a rotor, on the shaft of which two permanent magnets with the same concave poles of the same name are installed, and a stator made in the form of half-rings connected by means of non-magnetic inserts with two annular windings connected in series.

The disadvantage of the prototype is that the EMF in the windings is created through the air gap with the direct interaction of the magnetic poles of the rotor with the windings, and the currents flowing in the stator windings form magnetic lines of force on their surface, directed in the opposite direction of rotation of the magnetic poles of the rotor, which ultimately reduces the efficiency of the generator. When the machine is operating in the generator mode, the electromagnetic torque acts against the rotation of the armature, i.e. is braking (see article "Electromagnetism", 06.10.2014, posted online access on the Internet at: http://electromagnetizm.blogspot.com/2014/10/blog-post.html).

Also, a significant disadvantage of the prototype is the presence in the rotor of two permanent magnets with the same concave poles, which limits the possibility of efficient execution of the rotor with electromagnetic excitation of its poles.

In addition, in the presence of multi-turn rows of windings, the stator magnetic circuit moves away from the magnetic poles of the rotor, adversely affecting the generator power.

The objective of the invention is to create a single-phase alternator with high efficiency due to the removal of magnetic fluxes created by the currents of the annular windings from the stator teeth, while ensuring the simplicity of the design of the generator.

The invention is aimed at achieving a technical result, which consists in increasing the efficiency of a single-phase alternator by reducing the effect of magnetic fluxes in the stator, which cause braking of the rotation of the magnetic poles of the rotor.

The specified technical result is achieved by the fact that the single-phase alternator contains the same screens in the form of arc-shaped plates rigidly mounted on the stator on its two sides with a tight fit in the gaps between the annular stator windings, which are evenly spaced around the circumference in the amount , at least two and are connected in parallel opposite, while these screens are made with the possibility of diverting magnetic fluxes created by the currents of the annular windings from the stator teeth and the area of each screen exceeds the area of contact with the stator, while the stator has an annular shape, at least , with four internal teeth, and the rotor is provided with at least four magnetic poles mounted on the shaft c. order of alternating radial magnetic orientation of the poles.

In the proposed stator generator with teeth, the interaction of the poles of the rotor magnets with the annular stator windings is carried out not directly through the air gap, but through intermediate elements - teeth, with a minimum gap, while the magnetic fluxes created by the winding currents are closed around the stator perimeter and shunted by screens, thanks to which reduces the degree flow direction to the stator teeth, which as a result increases the efficiency of a single-phase alternator.

It is preferable that the single-phase alternating current generator be configured to control the magnetic resistance of the screens by changing their radial and axial dimensions.

It is advisable that in a single-phase alternator the magnetic poles of the rotor are made in the form of permanent magnets or with electromagnetic excitation.

It is necessary that in a single-phase alternator the number of installed annular stator windings be two times less than the number of magnetic poles of the rotor and at least two times less than the number of stator teeth.

These features are essential and are interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result.

The present invention is illustrated by a specific example of execution, which, however, is not the only possible one, but clearly demonstrates the possibility of achieving the desired technical result.

1 is a front view of a single-phase alternator according to the invention of FIG. 2 is a left side view of FIG. one; fig. 3 is a right side view of FIG. one; fig. 4 - front view of the stator; fig. 5 is a side view of FIG. 4; fig. 6- front view of the screen; fig. 7 is a side view of FIG. 6; fig. 8 - phase of rotation of the rotor from the initial position, which forms the output electrical signal; fig. 9 - phase of rotation of the rotor, during which an electrical signal appears at the output of the generator, opposite in sign to the previous phase.

According to the present invention, the design of a single-phase alternator is considered, in which the influence of magnetic fluxes that occur in the stator windings and operate in the mode of braking the rotation of the magnetic poles of the rotor is reduced. The essence of the invention is based on a change in direction magnetic fluxes created by winding currents, their closure around the stator perimeter and shunting by screens, thereby reducing the degree of flux direction to the stator teeth, which as a result increases the efficiency of a single-phase alternator.

In the general case, a single-phase alternator contains a stator with ring windings, a rotor mounted for rotation inside the stator with magnetic poles-inductors located on its shaft. The generator is equipped with identical arc-shaped screens in plan, rigidly mounted on the stator on its two sides with a tight fit to it in the gaps between the annular stator windings, which are evenly spaced around the circumference in the amount of at least two and are connected in parallel opposite.

The screens are made with the possibility of diverting the magnetic fluxes created by the currents of the annular windings from the stator teeth. The area of each screen in the plan exceeds the area of the contact surface with the stator. Each screen may consist of one plate or a set of plates.

The ring-shaped stator is made with at least four internal teeth, and the rotor is equipped with at least four magnets mounted on the shaft in the order of alternating alternation of the radial magnetic orientation of the poles.

The closure of the stator windings created by the currents, magnetic fluxes between themselves along the stator perimeter and their (magnetic fluxes) shunting by screens leads to a decrease in the level of magnetic induction on the stator teeth, thereby reducing the degree of braking of the magnetic poles of the rotor during its rotation and mechanical costs, which leads to to increase the efficiency of a single-phase alternator.

Below is a specific example of the invention (Fig. 1-9).

The single-phase alternator contains a rotor 1, on the shaft of which at least four magnetic poles are installed in the form of permanent magnets 2 or magnets with electromagnetic excitation. These magnets are evenly located in the plane of rotation on the shaft of the rotor 1 in the order of alternating alternation of the radial magnetic orientation of the poles. The rotor with magnetic poles is mounted for rotation inside the stator 3, made of an annular form of electrical steel and with at least four internal teeth 4 on the inner wall, facing radially and between which nests are formed for placing annular windings 5 and 6 (Fig. 1, 4). The teeth are protrusions radially directed to the axis of rotation of the rotor with concave wall surfaces facing the rotor. This design of the teeth is used to minimize air gaps between the projections and the annular windings located between them.

The stator 3 contains evenly spaced along its circumference between the teeth 4 (Fig. 4) and connected in parallel oppositely annular windings 5 and 6 in an amount two times less than the number of poles of the magnets 2 of the rotor 1 and at least two times less than the number teeth 4 of the stator 3.

The uniform arrangement of the windings 5 and 6 around the circumference, as well as the ratio of their number of 1: 2 to the number of poles of the magnets 2 of the rotor, during the operation of the generator, the same direction of the magnetic fluxes created by the windings 5 and 6 along the circumferential perimeter of the stator 3. This is due to the symmetry of the interaction during operation generator with windings 5 and 6 through the teeth 4 of the stator 3 of the same magnetic poles of the magnets 2 of the rotor 1 at any angular moments of rotation of the rotor 1, since the same poles of the magnets 2 diametrically opposite each other (during the rotation of the rotor) simultaneously pass in the same time intervals the same angular sections of the teeth 4 of the stator 3, between which the windings 5 and 6 are located. Accordingly, the currents of these windings 5 and 6, when the load is connected, will create magnetic fluxes of the same direction, closing among themselves along the perimeter of the stator 3.

The sections of the stator 3 with windings 5 and 6, as a rule, have a smaller cross-sectional area than the sections of the stator between the teeth without winding (Fig. 1 and 4). With a larger cross-sectional area of the sections of the stator 3 between the teeth without winding, their magnetic resistance will be less than the sections of the stator 3 with windings. In this case, the magnetic fluxes created by the windings 5 and 6 under the influence of the load will be removed from the teeth to a greater extent, closing along the perimeter of the stator 3.

It is known from the prior art that when an inductor is placed in a casing made of a ferromagnet, the lines of induction of the external magnetic field will go along the walls of the protective screen, since it has a lower magnetic resistance in relation to the space inside it. Those lines of force which are induced by the coil itself in the same way, almost all will close on the casing wall. For protection, choose materials that have high magnetic permeability, such as electrical steel or ferromagnets. To increase the reliability of the screen and its efficiency, this screen should be made of thick-walled or prefabricated from several elements of the same type such as plates. At the same time, it was found that the effectiveness of the screen drops sharply if there are seams or cuts in the screen. The screen must be monolithically uniform in its structure and homogeneous, since it is the cuts, cutouts and seams that cut the magnetic flux and violate the lines of its distribution. In addition, it is also established that the contact fit or fastening of the screen should be as tight as possible and not have air gaps or sinuses (Art. "Shielding of the magnetic field: principles and materials. Relative magnetic permeability of materials", https://fb.m/ article/458007/ekranirovanie-magnitnogo-polya-printsipyi-i-materialyi-otnositelnaya-magnitnaya-pronitsaemost-materialov).

In this regard, the claimed generator contains four identical arcuate shapes in terms of the screen 7-10 in the form of flat steel plates (each made from one plate or a set of plates) made of electrical steel (Fig. 1, 3, 6 and 7). These screens are made with teeth 11, repeating the shape of the teeth on the stator. The screens are rigidly mounted on the stator 3 in the areas between the windings 5 and 6 on both sides of the stator 3 and are tightly attached to the end surface of the stator 3. The screens are designed to divert the magnetic fluxes created by the currents of the windings 5 and 6 from the teeth 4 of the stator 3 in the direction sections between the teeth without windings, along the stator perimeter encyclopedia" at: https://bigenc.ru/phvsics/text/2153044).

Screens 7-10 are made with a flat surface area (in plan), exceeding the surface area of their contact with the end wall of the stator 3 (Fig. 1). This is done in order to reduce their magnetic resistance, which makes it possible to more shunt the magnetic fluxes created by the currents of the windings 5 and 6 along the perimeter of the stator 3, in the direction of the sections of the stator 3 between the teeth without winding. This reduces the magnetic induction on its teeth. Decrease The magnetic resistance of screens 7-10 (except for increasing their area) can also be achieved by increasing their thickness.

In FIG. 2, 3 and 7 show screens consisting of a set of electrical steel plates tightly adjacent to each other. Thus, the regulation of the magnetic resistance of the screens can be carried out by changing the radial and axial dimensions of the screens.

Magnetostatic shielding is based on the closure of the magnetic field in the thickness of the shield, which has an increased magnetic permeability. The screen material must have a magnetic permeability significantly greater than the magnetic permeability of the environment (see "Materials for magnetic alloys" Educational and methodological manual for laboratory work on the discipline "Materials Science and Technology of Structural Materials", State Educational Institution of Higher Professional Education Tomsk Polytechnic University, Tomsk , 2005, TPU publishing house, pp. 4, 5).

A single-phase alternator with an annular stator winding operates as follows.

In a single-phase alternator connected to the load, during the rotation of the rotor shaft 1, the magnetic poles interact with the teeth of the stator 3 (Fig. 8 and 9). In FIG. 8 and 9 show the main phases of the operating state of the generator, explaining its performance.

In the phase of rotation of the rotor shaft 1 shown in Fig. 8, the magnetic induction of the poles of the magnets 2 of the rotor creates magnetic fluxes F1 and F2 through the minimum air gap with the teeth of the stator 3, penetrating windings 5 and 6. At the same time, the currents of these windings 5 and 6 under the influence of the connected load 12 form magnetic fluxes FZ and F4, having the same direction and which are interconnected along the perimeter of the stator 3, through the screens 7-10, thereby reducing the level of magnetic induction created by the windings 5 and 6 on the teeth of the stator 3.

Similarly, in the next phase of rotation shown in FIG. 9, when the rotor shaft is rotated by 90°, the same processes of closing magnetic fluxes will occur, but only their direction will change to the opposite. In this case, the polarity of the electrical signal will change at the output of the generator. Due to the periodicity of the phase change (Fig. 8, 9), when the rotor 1 rotates, a continuous alternating current is formed at the output of the generator. The closure of the windings 5 and 6 created by the currents of the magnetic fluxes FZ and F4 between themselves along the perimeter of the stator 3 and their shunting by screens 7-10 reduces the level of magnetic induction on the teeth of the stator 3, thereby reducing the degree of braking of the magnetic poles of the rotor during the rotation of the rotor shaft 1 and mechanical costs, which leads to an increase in the efficiency of a single-phase alternator.

Thus, the use of the invention makes it possible to increase the efficiency in single-phase alternating current generators while simplifying the design of the generator itself.

Claims

Claim

1. A single-phase alternator containing a stator with ring windings, a rotor placed inside the stator with magnetic poles mounted on it, located in the order of alternating alternation of the radial magnetic orientation of the poles, characterized in that it contains four identical arcuate shapes in terms of a screen made of electrical steel to divert magnetic fluxes generated by the currents of the annular windings from the stator teeth, which are made in the form of flat steel plates with a surface area in terms of each screen greater than the contact area of each screen with the end wall of the stator, having an annular shape, on the inner surface of which at least four internal teeth in the form of radially directed protrusions, a rotor equipped with at least four magnetic poles, while the screens are rigidly attached to the stator from its two end sides with a tight fit between the annular stator windings, which which are evenly spaced between the teeth along the circumference in the amount of at least two and are connected in parallel oppositely.

2. The generator according to claim. 1, characterized in that it is made with the ability to control the magnetic resistance of the screens by changing their radial and axial dimensions or surface area in plan.

3. The generator according to claim 1, characterized in that the magnetic poles of the rotor are made in the form of permanent magnets or with electromagnetic excitation.

4. Generator according to claim 1, characterized in that the number of installed annular stator windings is two times less than the number of magnetic poles of the rotor and at least two times less than the number of stator teeth.

5. The generator according to claim 1, characterized in that each screen consists of one plate or a set of plates.

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