RU216039U1 - Electric Axial Flow Machine - Google Patents

Abstract

The utility model relates to the field of electrical engineering. The technical result is an increase in the fill factor of the stator winding with a winding wire. The magnetic system of an axial flow synchronous electric machine consists of a two-layer stator winding and a rotor consisting of two coaxial disks located on both sides of the stator winding and containing permanent magnets. The winding coils have clearly defined frontal parts, bent relative to the plane of the turn at an angle as close as possible to 90 degrees, the thickness of the coil sections, forming a non-magnetic gap, decreases when moving along the radius from the axis of the magnetic system to the edge, the section of the coil by a plane transverse to the winding wire, by any section of the coil remains unchanged, on the rotor there are pole and interpole permanent magnets, the thickness of which increases with the radius. 9 ill.

Description

The proposed utility model relates to electromechanical energy converters, in particular, it is applicable in traction electric motors, for example, built into a vehicle wheel, in torque motors, for driving various actuators, as alternators in power supply systems, including in the field distributed and renewable energy and other applications.

Known utility model RU 152538 U1, which proposes the design of an axial flow electric machine with a two-layer distributed winding. Such a winding involves the overlapping of the planes of the coils located in different layers, therefore, in order to assemble the coils in the utility model, it is proposed that the frontal parts of each coil be bent at a certain angle to the plane of the coil. From the diagram proposed in utility model RU 152538 U1 of the stator winding of an axial flow electric machine, it can be seen that at the base of the coils, the filling of the winding area with wire is maximum (sections of adjacent coils are tightly adjacent to each other), however, with an increase in the radius, a space free from the winding wire appears ( voids), which is filled with the compound. The presence of these voids is a disadvantage of the proposed scheme, and reduces the efficiency of the electric machine.

Known patents US 20130002066 A1, US 20160365755 A1, US 8823238, US 10141822, which also proposes the design of an axial flow electric machine. The authors of the patents pay due attention to the issue of increasing the stator fill factor of such machines. The technical solutions proposed in US 20130002066 A1, US 20160365755 A1, US 8823238, US 10141822 provide a very high fill factor of the stator with a winding wire, however, two important drawbacks should be noted that the authors of the corresponding patents miss:

1) a high fill factor is actually ensured by the use of a large number of coils, which leads to the fact that these electrical machines are fundamentally multi-pole;

2) the proposed geometry of the coils of the two-layer winding is such that the sections of each coil are located in different planes (one section in the upper layer of the two-layer winding, the second section, respectively, in the lower layer), this leads to the fact that the non-magnetic gap is determined by the size of the double thickness of one section coils, which reduces the magnetic field in the working gap of the machine.

This application proposes a magnetic system of an axial flow synchronous electric machine, which consists of a two-layer stator winding 1 and a rotor consisting of two coaxial discs 2 located on both sides of the stator winding and containing permanent magnets 3. This magnetic system is characterized in that winding coils have clearly defined frontal parts, bent relative to the plane of the coil at an angle as close as possible to 90 degrees, while the thickness of the coil sections, forming a non-magnetic gap, decreases when moving along the radius from the axis of the magnetic system to the edge, the section of the coil by a plane transverse to the center line coil, on any section of the coil is kept unchanged. This coil geometry makes it possible to achieve the maximum possible fill factor of the stator winding with winding wire and, as a result, to provide the winding geometry with a non-magnetic gap that is uneven along the radius. Also on the rotor are pole and interpole permanent magnets, the thickness of which increases with the radius, thereby providing a non-magnetic gap that is uneven along the radius.

On FIG. 2 shows the appearance of a two-layer stator winding of an axial flow electric machine with the highest possible fill factor of the stator winding with a winding wire. This stator winding refers to an electric machine with four pairs of poles, and consists of twelve coils, six coils in each layer. The winding is three-phase, each phase has four coils. The utility model assumes that the number of pole pairs can be: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. Accordingly, the coils in the winding can be: 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, etc.

On FIG. 3 shows the appearance of the stator winding coil. Coil thickness decreases with radius. In this case, the geometry of the coil is such that the cross section by a plane perpendicular to the center line of the coil remains unchanged at any point.

On FIG. 4 and 5 show sections of the coil in different planes. Sections of the same size are marked with the symbol S.

On FIG. 6 shows a sketch of the coil. The geometry of the coil is such that the following equality holds:

On FIG. 7 shows the rotor disk of an axial flow electric machine with permanent magnets mounted on it for the case when the number of pole pairs is four. The rotor consists of two identical discs located coaxially on both sides of the stator. The rotor contains pole and interpole permanent magnets. So for an eight-pole rotor, the number of pole magnets (magnetized parallel to the axis of rotation of the rotor) is eight, the number of interpole magnets is also eight. On FIG. 7 shows the directions of the magnetization of the magnets on the disk with arrows.

, верхнее основание -

, зазор между магнитами на расстоянии от оси ротора равном внутреннему радиусу магнитов через

, тогда зазор на расстоянии от оси ротора, равном наружному радиусу магнитов будет равен

.On FIG. 8 shows a sketch of the magnetic system of an axial flow electric machine. It can be seen that the permanent magnets have a variable thickness. Thus, the gap between the magnets is not uniform along the radius. If the lower base of the magnet section is denoted

, upper base -

, the gap between the magnets at a distance from the rotor axis equal to the inner radius of the magnets through

, then the gap at a distance from the rotor axis equal to the outer radius of the magnets will be equal to

.

The essential features of the claimed utility model include the magnetic system of an axial flow electric machine, which consists of a three-phase stator winding and a rotor in the form of coaxial disks with permanent magnets, the geometry of which is such that the non-magnetic gap decreases with radius, and the fill factor of the stator winding with winding wire is maximum for round wires.

As shown in FIG. 9, the magnetic field in the working gap of the axial flow electric machine in the case of an uneven gap increases almost throughout the working gap and becomes more uniform. The field increases especially strongly in the region of the outer radius of the permanent magnets.

Claims (1)

The magnetic system of an axial flow synchronous electric machine, which includes a two-layer stator winding, consisting of coils, the geometry of which is such that their frontal parts are bent relative to the coil plane at an angle as close as possible to 90 degrees, the thickness of the coil sections, forming a non-magnetic gap, decreases with moving along the radius from the axis of the magnetic system to the edge, the section of the coil by a plane transverse to the middle line of the coil, in any section of the coil remains unchanged and the rotor, consisting of two coaxial disks located on both sides of the stator winding and containing pole and interpole permanent magnets with increasing with a radius of thickness, forming a non-magnetic gap decreasing with the radius.

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