SU1629950A1 - Linear inductor electric motor - Google Patents

Abstract

The invention relates to electrical engineering and can be used in a linear precision electric drive. The goal is to improve the accuracy of thrust control. The motor consists of a gear ferromagnetic stator and a movable element consisting of phase electromagnetic modules. Each module includes U-shaped magnetic cores, a control winding and a permanent excitation magnet. The magnetic cores of the electromagnetic modules and the magnetic core of the stator can be made in the form of sections. A positive effect is achieved due to the fact that at least two magnetically conducting elements belonging to one phase are displaced from one another along the direction of motion by an angle (n - + - + 1/4) 2n, where n is any integer. 6 hp f-ly, 3 ill. (O S /)

Description

The invention relates to electrical engineering and can be used in a linear precision electric drive.

The purpose of the invention is to improve the accuracy of power control.

FIG. 1-3 presents constructive options for the engine.

The motor comprises a ferromagnetic toothed stator 1 and a movable element consisting of phase electromagnetic modules 2-5. Each module includes U-shaped magnetic cores 6 and 7, a control winding 8 and a permanent excitation magnet 9. The magnetic cores 6 and 7, the magnetic core of the stator I can be made in the form of sections 10 and 11, 12 and 13, 14 and 15. At least two magnetically conducting elements belonging to the same phase are displaced relative to each other along the direction by an angle n + 1 / 4) 2, where n is any integer.

Magnetically conductive elements belonging to the same phase and shifted relative to each other by an angle (n ± 1/4) 2, where n is any integer, may be the magnetic cores 6 and 7 in the electromagnetic modules x 2 and 3 (Fig. 1), the electromagnetic modules 2 and 5, 3 and 4 (Fig. 2), sections 14 and 15 of the magnetic circuit of the stator 1, sections 10 and 11, 12 and 13 of the magnetic cores 6 and 7 of the electromagnetic modules 2 and 3 (Fig. 3).

The motor windings are powered by control currents.

The magnetic flux created by them will amplify the flux of permanent magnets under the corresponding teeth of the U-shaped magnetic circuits. As a result, the pulling force acting on the moving element of the engine will occur.

When powering the motor windings with sinusoidal currents

SE Yu

co

gA-gc-5sh (f + f0), i i0cos (),

where f 2l / t; - the angle determining the position of the moving element of the engine relative to the stator;

x is the linear position of the movable element;

i - pitch of the dents zone of the engine;

Ф - initial displacement; i0 is the amplitude of the control currents. It is possible to control the engine thrust power by adjusting the amplitude of the 10 control currents.

The control currents gd and i & are formed in accordance with the position information of the moving element of the engine at each time point.

With such control of a known linear inductor motor 1, the thrust force generated contains a main component proportional to the amplitude of the control currents and an additional parasitic component.

The proposed engine is characterized by a higher accuracy of thrust force control. This is achieved by consistently and cyclically one of the magnetic conductors creating a force opposite to the direction of motion, due to which compensation of the parasitic component of the thrust force is achieved.

In accordance with the well-known method of calculating electromagnetic modules 2, a module replacement circuit is constructed. The work force of a module is represented as the sum of the efforts developed by its poles. These components of the pull force are determined by the parameters of the module replacement circuit.

First, the thrust force developed by the first engine is determined (Fig. 1).

We obtain that phase modules 2 and 3 will develop traction efforts.

Ј ("HF-Ј)

J

"L

Hso $ 2f;

U,

"SHfc P-f- - $ Ј-

X so52f)

where.,) &

FA, FR and Fm are MDS windings 8 of control and permanent magnets 9 of excitation;

- constant component and amplitude of change of the magnetic conductivity of the gap; Ya.sh and K $ are the internal magnetic conductivity and the conductivity of the scattering of permanent magnets 9.

Kfr

0

0

five

0

five

0

When forming MDS

WITH

FA o) gd ((f-y). G-Fe - aii u ijcos (p-Ј-)

the engine will develop the power of gi

))

containing the main component proportional to the amplitude of the control currents and the additional parasitic component.

Next, the thrust force developed by the second engine is determined (Fig. 2).

Modules 2-5 will develop trade-off forces, respectively, equal to

(FmhmSiivp + F2-Ј-sin2 p); ntl

F3--4j-F3 (FmKmcos p-F3- $ jrSin2 (p);

HI%

(Fmb "s nq + F4-Ј-sin2q);

L,

F5 -9 $ - F5 (FmKmcos (p-Fs -% - sin2y). Nik

where F2, Fa, F and F $ are MDS control windings of modules 2-5.

Since the single-phase modules 2 and 5.3 and 4 are fed in pairs by identical currents, then, according to the obtained result, the engine will develop thrust force.

f F2 + F3 + F4 + fs -J | t- / r «A.m (F2-f4) X

t

(F3 + F5) cos (f). Consequently, when forming MDS

2 (f + y); / G3 / 4 Yug0S05 (f + -)

the engine will develop the power of gi

(2)

. VJJgir.

Г ОМ0 ft Г тАт

The pulling force is proportional to the amplitude of the control currents. The parasitic component in the engine thrust is absent.

Then the thrust force developed by the engine shown in FIG. 3

Imagine this motor as rigidly coupled motors with common control windings. The first engine contains, as U-shaped magnetic conductors, sections 10 and 12 of modules 3 and 2 and a stator section 15. The second engine, respectively, includes sections 11-14.

We obtain that the first and second engines will develop traction efforts equal to

Fi - fyj - FmXm (Fn sin (f - {- F & coscp) +

+ $ Ј (% - ®sin2 p, T2 - -RtKt (PA cos (f-Fe sirup) -

 L and FA - MDS control windings. Consequently, the full power of the engine gi will be equal to

 + (F sm (cp + Ј) +

(3)

+ Јcos (P + | -)).

MDS winding control

ЈЈ

Ј o) / 051Hf + y-); 4 w / 0cos (cp4-f-) Substituting these values of MDS in expression (3), we arrive at the fact that the engine will develop the thrust force described by expression (2). As in the previous case, the parasitic component in the engine thrust is absent.

A similar result occurs when offset relative to each other by an angle l / 2 of sections 10 and 11, 12 and 13 of the magnetic wires 6 and 7 in the electromagnetic modules 2 and 3.

Phase modules of a known engine develop traction forces.

FA - (FmKmsin (

F & (% -F0 (FmumCosy% f-F0sin2cf).

As a result, in the formation of MDS

FA OMO5Shf, F & Sh0CO5f,

the engine develops the power of ti Fr% + fc Mo-fy (Fmka-iM0-j -Sin44) (4)

The pull force contains the main component, which is proportional to the amplitude of the control currents, and the parasitic component.

The coefficient of instability, t, is introduced into consideration, which is equal to the ratio of the amplitude of the parasitic component to the main force. According to (4) get that

and -. "And of1.

6 4FmXm

The instability factors that characterize the considered variants of the proposed engine are determined. In accordance with (1) and (2) receive

AZ .9) А-т + АбТ1 | 7 / -GT -GGZG-L-. 1 4Л / 2Ј0 / g, Dt

0

The result obtained directly confirms mainly the second and third variants of the proposed engine, since their coefficient of instability is zero. The advantage of the first variant of the engine over the known engine is realized when

A ..

i.e., when the sum of the internal magnetic conductivity KT of the permanent magnet and the conductivity of its scattering Ab is less than the constant component of the magnetic conductivity of the working gap §0.

Nowadays, permanent magnets based on

barium ferrites, rare earth metals (REM). The magnetic permeability of the substance of such magnets is close to the permeability of air. Since it is characteristic of linear inductor motors that the gap in the dentate zone of the motor is much smaller than the thickness of the permanent magnets used, the required inequality (5) will always occur.

Thus, the proposed linear inductor motor has the advantage over the known motor, since it is characterized by a higher accuracy of thrust control. In this case, the first engine variant is the simplest structurally. The second variant of the engine has the distinctive feature that, if there is a restriction on the width of the engine, it allows one to achieve the greatest thrust force. The displacement of the sections of the magnetic cores makes it possible to obtain the accuracy of the adjustment of the force of gi achieved by doubling the number of modules

5 and their relative offset. The mixture of sections of the magnetic circuits of the electromagnets of the modules or sections of the stator is selected taking into account the design features of the developed equipment based on linear motors and ISO technology.

cooking.

Claims (7)

1. Linear inductor motor containing a ferromagnetic toothed stator and a movable element consisting of phase electromagnetic modules including U-shaped magnetic cores, control windings and permanent excitation magnets, characterized in that, in order to increase the accuracy of controlling the pull force, at least two magnetically conducting elements, belonging to the same phase are shifted relative to each other along the direction of motion. 2. The motor according to claim 1, characterized in that the offset is an angle (n ± ± 1/4) -2l, where n is any integer. 3. The engine for PP. 1 and 2, characterized in that said offset is made between the magnetic cores in the electromagnetic module. 4. The engine of PP. 1 and 2, characterized in that said displacement is made between two electromagnetic modules. 5. The engine for PP. 1 and 2, characterized in that the ferromagnetic gear stator and electromagnetic magnetic cores modules are divided into sections in a direction perpendicular to the direction of motion. 6. The motor according to claim 5, characterized in that said displacement is performed between the sections of the magnetic circuit. 7. The motor according to Claim 5, characterized in that said offset is made by sections of the magnetic cores. Phase A  (n-j) 2ff About 2nd btg Have Phase A Phase B Phase B (n-j) 2if .i TO ig. one Phase B Phase A CQ C3 I X | J Cem i 53 % Sj J J fe four  , nJ