RU2541427C1 - Terminal electric machine (versions) - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: terminal electrical machine contains a stator with a toroidal magnetic conductor and a coil winding, a disk rotor with permanent magnets with axial magnetisation and alternating polarity (or ferromagnetic rotor cores), bearings and a shaft. The rotor is rigidly fixed on a shaft and rotates thanks to the bearing with reference to the stator. Number of couples of rotor poles p, number of stator teeth Z are related by equations for three-phase winding (m=3) for Z=y·m·k: p=y·k, (y+1)·k, where y=1; p=(y+1)·k, (y+2)·k, where y=3, 4; p=(y+2)·k, (y+3)·k, where y=5; p=(y+3)·k, (y+4)·k, where y=7; p=(y+3)·k, (y+5)·k, where y=8; p=(y+4)·k, (y+5)·k, where y=9; p=(y+5)·k, (y+6)·k, where y=11, and y, k - integer positive values.

EFFECT: obtaining of low rotating terminal electrical machine with the maximum capacity at the pre-set dimensions.

19 cl, 2 dwg

Description

The invention relates to electrical engineering, in particular to electric machines, and can be used in special electric drives as low-speed electric motors and electric generators.

Known Electromechanical converter (Patent RU 2441308 C1, author Zakharenko AB IPC H02K 19/10), containing at least one stator-rotor pair, in which the stator consists of cores of material with high magnetic permeability, the ends attached to the supporting stator ring and oriented parallel to the main magnetic flux, and between which the multiphase winding conductors are located, the rotor is made in the form of two coaxially located external and internal inductors - magnetic cores made of a material with high magnetic permeability in the form of hollow cylinders, rotatably fixed relative to the stator, bearing alternating poles located around the circumferences of the pole, facing the stator through working gaps and covering it, while the polarity of the poles located on the inner and outer inductors is opposite to each other, characterized in that the number of pole pairs p, the number of stator cores Z are related by:

- for a two-phase winding (m = 2):

for Z = y · m · k p = (y-1) · k, (y + 1) · k, where y is an even number, y≥4; k is a positive integer;

- for a three-phase winding (m = 3) for Z = y · m · k:

p = y · k, (y + 1) · k, where y = 1;

p = (y + 1) · k, (y + 2) · k, where y = 3,4;

p = (y + 2) · k, (y + 3) · k, where y = 5;

p = (y + 3) · k, (y + 4) · k, where y = 7, 8 *;

p = (y + 4) · k, (y + 5) · k, where y = 9;

p = (y + 5) · k, (y + 6) · k, where y = 11,

moreover, y, k are positive integers.

A disadvantage of the analogue of the Electromechanical converter is the cantilever mounting of the rotor inductors, which, due to the presence of magnetic attraction between the stator and the rotor, does not allow to increase the diameter of the machine. An increase in diameter would have a beneficial effect on the increase in electromagnetic power. In addition, based on the choice of the MDS with the maximum amplitude as the main harmonic, the best options for m = 3, Z = 24, y = 8, k = 1 are the options with 2p = 22, and 2p = 24. The coincidence of Z and 2p is unacceptable due to the undesirably stable position of the stator teeth opposite the rotor magnets. Thus, the ratio marked with "*" is not true, it should be clarified.

The closest in technical essence to the present invention is the end magnetoelectric machine (options) (Patent RU 2337458 C1, authors Zakharenko AB, Chernukhin VM, IPC H02K 26/00), containing a stator with a toroidal magnetic circuit and coil winding, disk rotor with permanent magnets with axial magnetization and alternating polarity, bearings and shaft, characterized in that the stator is rigidly mounted on the shaft, and the rotor rotates in bearings relative to the shaft axis, the number of coils in the stator coil group b = 2, 3, 4, 5 ... - the whole ozhitelnoe number greater than or equal to 2 and the number of d-phase coil groups, the number Z of the stator teeth and the number p of pairs of poles of the rotor are related by:

1 <Z / p <4,

moreover, Z / p ≠ 2, and

p / d = k,

where k = 1, 1.5, 2, 2.5, 3, 3.5 ... is a positive integer, or a number different from it by 0.5, if k is an integer, the windings of the coil groups in each phase are connected according to, and when k is different from integer by 0.5, the windings of the coil groups in each phase are connected in opposite directions.

The disadvantage of the prototype is that the dependencies proposed in it do not give exactly the best relations between the number z of stator teeth and the number 2p of rotor poles. So, for example, in table 1 of patent RU 2337458 C1 the following best ratios are given for m = 3, Z = 24, 2p = 16, 20, 22, 26, 28, 32. It is not clear which (or which) of the ratios is the best, based on the choice of the MDS with the maximum amplitude as the main harmonic (usually there are two higher harmonics with maximum amplitudes). In addition, the prototype did not consider the possibility of obtaining an end electric machine without permanent magnets.

The aim of the present invention (according to option 1) is to clarify the most optimal ratios between the number Z of stator teeth and the number 2p of rotor poles for an end electric machine, as well as to obtain an end electric machine with the best properties without permanent magnets (according to option 2).

The technical result of the present invention (for both options) is to obtain a low-speed end-face electric machine with maximum power for a given size.

Based on the maximization of the amplitudes of the two higher harmonics of the MDS for m = 3, z = 24, y = 8, k = 1, the following relations are necessary for p = (y + 3) · k, (y + 5) · k, i.e., 2p = 22, and 2p = 26, in other words, p = (y + 3) · k, (y + 5) · k, where y = 8. Other ratios, according to the authors, are correct and should be left unchanged as in the analogue. That is, the number of pairs of poles of the rotor p, the number of teeth Ζ of the stator should be related by the relations:

- for a two-phase winding (m = 2):

for Z = y · m · k p = (y-1) · k, (y + 1) · k, where y is an even number, y · 4; k is a positive integer;

- for a three-phase winding (m = 3) for Z = y · m · k: p = y · k, (y + 1) · k, where y = 1;

p = (y + 1) · k, (y + 2) · k, where y = 3, 4;

p = (y + 2) · k, (y + 3) · k, where y = 5;

p = (y + 3) · k, (y + 4) · k, where y = 7;

p = (y + 3) · k, (y + 5) · k, where y = 8;

p = (y + 4) · k, (y + 5) · k, where y = 9;

p = (y + 5) k, (y + 6) k, where y = 11,

while y, k are positive integers.

Both variants of the present invention are illustrated by figures 1 and 2.

FIG. 1. The design of the end electric machine.

FIG. 2. The stator winding circuit of the end electric machine with m = 3, Ζ = 12, k = 1. Dots indicate the beginning of the coils.

The design of the end electric machine (according to option 1)

The teeth 1 of the stator (anchor) are attached to the housing 2 of the stator. The teeth 1 and the housing 2 are made of soft magnetic material. The teeth of the stator 1 can be laced with their electrical steel, the housing 2 of the stator can be made of structural steel with high magnetic permeability. On the teeth of stator 1 there is a three-phase (m = 3) winding 3, where the letters A, B, C indicate the beginning of the corresponding phases, Χ, Υ, Ζ their ends. The winding may also have a different number of phases, for example m = 2. The stator winding coils 3 are wound from a winding wire, for example, copper enamel wire. The stator winding coils 3 are connected into coil groups (in FIG. 2, there are 4 coils in each phase of the coil group). To increase reliability, the coil group, or the phase as a whole, can be wound with a continuous wire. It should be noted that the coil groups can be connected to each other not only sequentially, but also in parallel (for k≥1), and also form parallel branches (connected in series-parallel) over several series-connected coil groups in case k = 4, 6 , 8, 10 an even number is greater than two. The three-phase stator winding 3 (m = 3) can be connected to a star, as well as to a triangle. Permanent magnets 5 magnetized in the axial direction are fixed on the non-magnetic base 4 of the rotor, the polarity of the magnets in the tangential direction alternates. The rotor (base 4 with permanent magnets 5 fixed to it) is rigidly fixed to the shaft 6 and rotates thanks to the bearing 7 relative to the housing 2 of the stator. The bearing 7 can be made, for example, ball bulk to reduce the axial length of the machine.

The principle of operation of the end electric machine (according to option 1)

The magnetic flux of each permanent magnet 5 passes through the air gaps between the stator and the rotor, the teeth 1 and the housing 2 of the stator.

In the motor mode, alternating voltage is applied to the clamps of each phase of the stator winding 3 of the synchronous electric machine, current flows through the winding, causing the stator to rotate MDS. Typically, the two harmonics of the MDS stator have the largest amplitude. The rotor is made with the number of poles equal to the number of poles of one of these harmonics. When electric current flows in the stator winding 3, the magnetic flux of the winding 3 interacts with the magnetic flux of permanent magnets 5. Moving, the MDS stator wave creates a torque acting on the rotor, the magnetic flux of permanent magnets 5 moves from one coil to the next, while inducing electromotive force (EMF) in the winding 3. The magnitude of the EMF is due to the magnitude of the magnetic flux of the poles and the rotational speed of the rotor. When the rotor rotates, the end-face electric machine will give mechanical power to the load.

The stator winding 3 is powered by an alternating current main or from an inverter. In the case of power from the inverter, for the most efficient operation of the machine in motor mode, feedback on the position of the rotor is introduced. The position of the rotor is determined by the readings of the position sensor. As a position sensor, a sine-cosine rotary transformer or a sensor based on the Hall effect (Hall sensor) can be used. When using the Hall sensor as a sensitive element of the rotor position sensor, it can be placed between the stator and the rotor on the side of the stator facing the permanent magnets of the rotor, directly in the main working air gap.

In the generator mode, the rotor of the end electric machine is driven into rotation by an external source of mechanical energy (engine), while the torque is applied to the rotor. The field of permanent magnets 5, moving with the rotor, crosses the stator winding 3, in which the emf is induced. If the load circuit is closed, current flows through winding 3. The resulting electrical energy is transferred to the load.

The design of the end electric machine (option 2)

The teeth 1 of the stator (anchor) are attached to the housing 2 of the stator. The teeth 1 and the housing 2 are made of soft magnetic material. On the teeth of stator 1 (armature) there is a three-phase (m = 3) winding 3, where the letters A, B, C indicate the beginning of the corresponding phases,,, Υ, Ζ are their ends. The winding may also have a different number of phases, for example, m = 2. The stator winding coils 3 are wound from a winding wire, for example, copper enamel wire. Coils are connected in coil groups. To increase reliability, the coil group, or the phase as a whole, can be wound with a continuous wire. It should be noted that the coil groups can be connected to each other not only sequentially, but also in parallel (for k≥1), and also form parallel branches (connected in series-parallel) over several series-connected coil groups in case k = 4, 6 , 8, 10 an even number is greater than two. The three-phase stator winding 3 (m = 3) can be connected to a star, as well as to a triangle. On the non-magnetic base 4 of the rotor, ferromagnetic cores 5 are fixed, made in the form of parallelepipeds made of soft magnetic material, for example, lined from electrical steel. The rotor (base 4 with cores 5) is rigidly fixed to the shaft 6 and rotates due to the bearing 7 relative to the housing 2 of the stator. The bearing 7 can be made, for example, ball bulk to reduce the axial length of the machine.

The principle of operation of the end electric machine (according to option 2) The magnetic flux generated by the stator winding 3 passes through the air gaps between the stator and the rotor, teeth 1 and cores 5, and the stator housing 2.

The end electric machine according to option 2 is essentially synchronous reactive and works only in motor mode. At the same time, alternating voltage is applied to the clamps of each phase of the stator winding 3 of the synchronous electric machine, current flows through the winding, causing the stator to rotate MDS. Usually the two harmonics of the stator MDS have the largest amplitude. The rotor is made with the number of poles equal to the number of poles of one of these harmonics. When an electric current flows in the stator winding 3, the magnetic flux of the winding 3 interacts forcefully with the ferromagnetic cores 5 of the rotor. Moving, the MDS wave of the stator creates a torque acting on the rotor. When the rotor rotates, the end electric machine will give mechanical power to the load.

The stator winding 3 is powered by an alternating current main or from an inverter. In the case of power from the inverter, for the most efficient operation of the machine, feedback on the position of the rotor is introduced. The position of the rotor is determined by the readings of the position sensor. A sine-cosine rotary transformer can be used as a position sensor.

Claims (19)

1. End-face electric machine (option 1), comprising a stator with a toroidal magnetic circuit and coil winding, a disk rotor with permanent magnets with axial magnetization and alternating polarity, bearings and a shaft, characterized in that the rotor is rigidly mounted on the shaft and rotates thanks to the bearing relative to the stator , the number of pairs of poles of the rotor p, the number of teeth Z of the stator are related by the relations for a three-phase winding (m = 3) for Z = y · m · k:
p = y · k, (y + 1) · k, where y = 1;
p = (y + 1) · k, (y + 2) · k, where y = 3, 4;
p = (y + 2) · k, (y + 3) · k, where y = 5;
p = (y + 3) · k, (y + 4) · k, where y = 7;
p = (y + 3) · k, (y + 5) · k, where y = 8;
p = (y + 4) · k, (y + 5) · k, where y = 9;
p = (y + 5) k, (y + 6) k, where y = 11,
while y, k are positive integers. 2. The end electric machine according to claim 1, characterized in that k≥1. 3. The end electric machine according to claim 1, characterized in that for even k, the coil groups of the same phase of the stator winding are connected in parallel. 4. The end electric machine according to claim 1, characterized in that the coil groups of the same phase of the stator winding are connected in series. 5. The end electric machine according to claim 1, characterized in that for even k> 2 coil groups of the same phase of the stator winding are connected in series-parallel. 6. The end electric machine according to claim 1, characterized in that the rotor disk is made of non-magnetic material. 7. The end electric machine according to claim 1, characterized in that the stator winding is powered by an alternating current network. 8. The end electric machine according to claim 1, characterized in that the stator winding is powered by a controlled inverter that allows the synchronous electric machine to operate in motor and generator modes. 9. The end electric machine according to claim 1, characterized in the presence of a rotor angular position sensor. 10. End electric machine (option 2), containing a stator with a toroidal magnetic circuit and coil winding, a disk rotor, bearings and a shaft, characterized in that the rotor is rigidly mounted on the shaft and rotates thanks to the bearing relative to the stator, ferromagnetic cores are placed on the disk rotor, number pairs of poles of the rotor p, the number of teeth Z of the stator are related by the relations for a three-phase winding (m = 3) for Z = y · m · k:
p = y · k, (y + 1) · k, where y = 1;
p = (y + 1) · k, (y + 2) · k, where y = 3, 4;
p = (y + 2) · k, (y + 3) · k, where y = 5;
p = (y + 3) · k, (y + 4) · k, where y = 7;
p = (y + 3) · k, (y + 5) · k, where y = 8;
p = (y + 4) · k, (y + 5) · k, where y = 9;
p = (y + 5) k, (y + 6) k, where y = 11,
while y, k are positive integers. 11. End electrical machine according to claim 10, characterized in that k≥1. 12. The end electric machine of claim 10, characterized in that for even k, the coil groups of the same phase of the stator winding are connected in parallel. 13. The electrical end machine of claim 10, wherein the coil groups of the same phase of the stator winding are connected in series. 14. The end electric machine of claim 10, characterized in that for even k> 2, the coil groups of the same phase of the stator winding are connected in series-parallel. 15. The electrical end machine of claim 10, wherein the rotor disk is made of non-magnetic material. 16. The end electric machine of claim 10, wherein the stator winding is powered by an alternating current network. 17. End electric machine according to claim 10, characterized in that the stator winding is powered by a controlled inverter that allows the synchronous electric machine to operate in motor mode. 18. The end electric machine according to claim 10, characterized by the presence of a rotor angular position sensor. 19. The end electric machine of claim 10, wherein the ferromagnetic rotor cores are made in the form of parallelepipeds of soft magnetic material.

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