RU2551125C2 - Method of compensation of centrifugal force of electrical machine rotor, and anti-centrifugal generator and anti-centrifugal electric motor for its implementation and their high-frequency power supply network - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to electrical equipment, to high-speed reversible rotating electrical machines in which due to compensation of centrifugal accelerations of the rotor its angular speed and power of the whole electrical machine significantly rises, and can be used as an electric drive for powerful high-performance centrifugal pumps and fans, for pumping of liquids and gases, in transport, especially water transport applications, and in closed power supply systems. The method of compensation of centrifugal force of rotor of the reversible electrical machine consists in control of magnetic field of rotor poles by constraining magnetic field induced by a co-directed parallel flow of currents in the rotor conductors located oppositely the values of which are proportional to the circumferential speed of the rotor. The device for compensation of centrifugal force of rotor contains a stator, a rotor, bearing and collector units. The stator has three alternating pairs of conductors connected parallel and hooked-up to a three-phase network. The rotor has minimum two conductors (poles) framing magnetically soft material of the rotor. The stator and the rotor have amount of conductors multiple to two, placed parallel. Grooves with conductors of the stator and the rotor are evenly distributed on their surfaces.

EFFECT: machine power increase.

4 cl, 27 dwg

Description

The invention relates to high-speed reversible rotating electric machines, in which due to the compensation of centrifugal accelerations of the rotor, its angular velocity and power of the entire electric machine are significantly increased. Such electric machines can produce a three-phase alternating current in generator mode and operate on a pulsating (rectified) current of the same three-phase alternating current as an electric motor. This, as well as the fact that the rotor of an electric machine (with a diameter of 0.5 m or more) is able to accelerate to high revolutions (30 thousand rpm and above) without mechanical damage and produce an increased frequency of alternating current (1 kHz and above) can serve the basis for creating a network of a new energy system is an anticentrifugal generator - a transformer - an anticentrifugal engine.

The invention can be used as an electric drive for powerful high-performance centrifugal pumps and fans, for pumping liquids and gases, in transport, especially water, and in closed power systems.

A device using the method of applying the restraining magnetic force of the North and South (NS) rotor magnet poles is an improved DC motor (German patent DE 3807377, H02K 25/00), in which the centrifugal force (tangential component) is restrained by the geometric arrangement of the magnet rotor sectors along the circumference of its radius, which allows these magnet sectors to be attracted to each other by the southern and northern sides and partially compensate for the centrifugal force during rotation rotor. This method of partial compensation of the centrifugal force acting on each sector of the rotor by attracting the N-S poles of these sectors is due to the use of magnetic force directed towards the centrifugal applied to each sector.

This known device or this electric motor has a number of disadvantages.

The method for compensating the centrifugal force of the rotor of a DC motor in Hanson Walter, H02K - 25/00, DE 3807377, 09.21.1989, Verbesserter Gleichstrom-Motor, consists in equidistant geometric arrangement of the rotor poles-magnets around its axis of rotation and the attraction of their opposite poles to each other, and the magnitude of the magnetic field of these permanent magnet poles is insignificant and is due to the limit of magnetization of materials, which leads to insignificant compensation of the centrifugal force acting on the rotor poles. This leads to a slight increase in centrifugally compensated peripheral speed and, as a consequence, to a slight increase in the specific power of the electric motor (W / kg).

The design of the rotor of the DC motor of the patent Hanson Walter, H02K - 25/00, DE 3807377, 09.21.1989, "Verbesserter Gleichstrom-Motor" allows only partially compensate for the centrifugal force acting on the rotor poles with counter magnetic force; those. The magnetic containment forces do not act on the entire cross section of the rotor, but only on the butt regions of the N-S poles of the rotor.

This device is the closest in technical essence and the achieved effect.

The objective of the invention is the creation of a reversible electric machine, which when operating in the generator or electric motor mode can have (i.e. output or convert), the specific power (W / kg) per lock is higher than that of modern asynchronous electric motors (generators). And as a result, the creation of a high-frequency, compact electrical system based on an anti-centrifugal generator - a transformer - an anti-centrifugal engine.

The problem is achieved in that in the proposed method for compensating the centrifugal force of the rotor of a reversible electric machine by restraining the magnetic field of the poles of the rotor by a restraining magnetic field, the restraining magnetic field of the rotor is caused by the co-directional current flow in the rotor conductors located diametrically opposite, and the magnitude of these currents is proportional to the peripheral speed of the rotor . The device for compensating the centrifugal force of the rotor of a reversible electric machine contains a stator, rotor, bearing and collector units, while it is equipped with a current regulator for the rotor of the electronic rectification unit, the stator has three alternating pairs of conductors connected in parallel and connected to a three-phase network, the rotor has no less than two conductors framing the soft magnetic material of the rotor, the stator and the rotor has a number of conductors multiple of two, laid in parallel. The grooves with the conductors of the stator and rotor are evenly distributed over their surfaces. The device measures the circumferential speed of the rotor with the transmission of a signal to the current regulator of the rotor of the electronic rectification unit.

As can be seen from the foregoing, the present invention has significant features that are different from the prototype, which allows us to conclude that this solution meets the criterion of "novelty."

Using co-directional parallel pulsating

(rectified) current to create a magnetic field of the rotor, the use of a device for measuring the peripheral speed of the rotor with the transmission of a signal to the current regulator of the rotor of the electronic rectification unit allows us to conclude that the proposed invention meets the criterion of "significant differences".

Further, the invention is illustrated by a detailed description of the principles underlying the method, and design options with reference to the accompanying drawings, which show:

in FIG. 1 diagram of an anti-centrifugal generator in a high-frequency electrical system;

in FIG. 2 diagram of an anti-centrifugal motor in a high-frequency electrical system;

in FIG. 3 rotor design of an anti-centrifugal electric machine;

in FIG. 4 image of forces acting on a body that moves in a circle;

in FIG. 5 image of the forces acting on conductors with a co-current flow of currents;

in FIG. 6 depicts the forces acting on the rotor conductors of an anticentrifugal electric machine, with one pair of conductors;

in FIG. 7 design of the rotor of an anti-centrifugal electric machine, with the image of forces acting on it;

in FIG. 8 varieties of rotor profiles;

in FIG. 9 depicts the forces acting on the rotor conductors of an anticentrifugal electric machine, with two pairs of conductors;

in FIG. 10 rotor design of an anticentrifugal electric machine with additional conductors, with the image of the forces acting on it;

in FIG. 11 depicts the forces acting on the rotor conductors of an anti-centrifugal electric machine with two pairs of conductors and the design of the rotor with six pairs of conductors;

in FIG. 12 rotor design inserted into the stator of an anticentrifugal electric machine (generator mode);

in FIG. 13 design of the rotor and stator of the anti-centrifugal electric machine with the image of the stator circuitry (generator mode);

in FIG. 14 cycle of operation of the anticentrifugal generator with 6 stator conductors at rotor angles of 0-45 °;

in FIG. 15 operation cycle of the anticentrifugal generator with 6 stator conductors at rotor rotation angles of 60-105 °;

in FIG. 16 cycle of operation of the anticentrifugal generator with 6 stator conductors at rotor rotation angles of 120-165 °;

in FIG. 17 cycle of operation of the anticentrifugal generator with 6 stator conductors at rotor rotation angles of 180-195 °;

in FIG. 18 current plots in phases of an anticentrifugal generator with 3 pairs of stator conductors (with a total resistance of one pair equal to X _total = 1 Ohm);

in FIG. 19 design of the rotor inserted into the stator of the anti-centrifugal electric machine (electric motor mode);

in FIG. 20 design of the rotor and stator of an anti-centrifugal electric motor with the image of limited and induced currents in an adjacent (next) pair of stator conductors;

in FIG. 21 design of the rotor and stator of the anti-centrifugal electric motor in operating mode with a partial image of the stator circuitry (electronic rectification unit is not shown);

in FIG. 22 cycle of operation of an anticentrifugal pulsating current electric motor with 6 stator conductors at rotor rotation angles 0-45 °;

in FIG. 23 operation cycle of an anticentrifugal pulsating current electric motor with 6 stator conductors at rotor rotation angles of 60-105 °;

in FIG. 24 cycle of operation of the ripple current anti-centrifugal electric motor with 6 stator conductors at rotor rotation angles of 120-165 °;

in FIG. 25 cycle of the anti-centrifugal generator with 6 stator conductors at rotor rotation angles of 180-195 °;

in FIG. 26 current graphs in phases of an anticentrifugal electric motor with 6 stator conductors (with 3 pairs), after conversion in the electronic rectification unit;

in FIG. 27 schematic of a high-frequency electrical system based on anti-centrifugal electric machines.

The anti-centrifugal electric machine contains a stator 1, a rotor 2, bearing 3 and collector 4 nodes, windings of the stator 5 and rotor 6 (Fig. 1, 2). A tachogenerator 7 connected to the thyristor rectification unit (rotor current regulator) 8 is installed on the rotor shaft.

The rotor 2 is made with a rectangular cross section or with a narrowing at the ends of soft magnetic material (ideally with a directly proportional, low-area hysteresis loop), the ends of which are framed by (copper) conductors 6 (Fig. 3). At the ends of the rotor conductors, its framing copper conductors end with hollow copper cylinders for collector contact. Moreover, the soft magnetic sector of the rotor 2 and the conductors 6 of the rotor 2 should be electrically insulated from each other. This is achievable, for example, when using insulating spray pads (with high compressive strength) or during other activities.

Ideally, the cross section of the conductors at the converging ends of the rotor should be equal to the cross section of the conductors in the middle part of the rotor (Fig. 3):

S ₁ = S ₂ = const (one)

The rotor (complete) is mounted on an axle or pulley, secured with axle dowels and nuts (on the sides).

The rotor section has a rectangular view (first section), or the compass needle (second section) (Fig. 3). The second section is specially designed for more convenient distribution of magnetic induction lines (to contain the rotor conductors).

The rotor currents I _2.1 , I _2.2 must be constant and equal to each other, they flow in parallel or parallel to the framing conductors (Fig. 3):

I _2.1 = I _2.2 = const, I _rot = I _2.1 (2)

In the operating mode (with the rotor electrically switched on), the rotor conductors inhibit centrifugal forces that affect the rotor sector during its rotation. Moreover, the forces of electromagnetic containment (Lorentz forces) caused by the current of the rotor conductors compress the rotor in proportion to the speed of rotation like a vice, provided that the current magnitude I _{rot is} proportionally changed.

To confirm the thesis of electromagnetic containment of the body and rotor conductors, we give some formulas.

Formula (3) determines the centrifugal force or tangential component applied to a point of a rotating body.

The centripetal force F _c makes the body move in a circle and does not allow the body to move inertia in a straight line (tangent to a circle). The inertia force that counteracts the centripetal force is called the centrifugal force and is denoted by F _cb (Fig. 4). Both forces are equal in magnitude and opposite in direction.

If F _cb is the centrifugal force, the inertia force acting along the radius from the center when moving in a circle, and _p is the radial acceleration of the rotor point, then the formulas for their determination are:

Or, taking into account the relationship of the angular velocity ω (rad / s = s ^-1 ) with the shaft speed

rotor n (r / s = s ^-1 ) we have:

Here:

υ - body speed (m / s),

ω is the angular velocity of the body (rad / s = 1 / s),

m - body weight (kg),

R is the radius of the circle (rotor) (m),

n is the number of rotor revolutions (r / s).

and _p is the radial acceleration of the rotor point (m / s ² ).

The formula for finding the electromagnetic force (Lorentz) of the interaction of two parallel conductors (stator) with co-currents has the form:

Here µ _c = µ µ ₀ is the magnetic permeability of the medium expressing the dependence of the force

the interaction of electric currents from the environment,

µ ₀ - magnetic constant (4π × 10 ^-7 N / A ² ),

µ is the relative magnetic permeability (p.u.),

a is the distance between the surfaces of the conductors (m),

D is the rotor diameter of the anti-centrifugal machine, taking into account the thickness of the conductors (m),

I ₂ - current conductor (part of the rotor) (A),

I _2.1 - current conductor (second part of the rotor) (A),

F _{Lor. 2} - force (N) acting on the left conductor and due to its current I ₂ ,

F _ENT.2.1 - force (N) acting on the right conductor and due to its current I _2.1 ,

l is the length of the long conductor (m), on which the force (s) F _{Lor. 2} , F _Lor . _{2.1 acts} .

In ₂ - magnetic induction of the field of the left conductor (current I ₂ ) (T).

The equilibrium condition of the centrifugal force F _cb force of electromagnetic containment (Lorentz) F _Lor.2 in a vector form ( _figure 5):

Where K ₁ and K ₂ are constant proportionality coefficients.

Obviously, when the coefficients K ₁ and K _{2 are} numerically equal, a change in the rotor containment current (s) I ₂ = I _2.1 will provide a directly proportional change in the rotor speed n (r / s) (Fig. 4, 5). Those. equalities (11) - (14) mathematically prove that it is possible to select such numerical values at which the centrifugal forces acting on the rotor will be fully compensated by the electromagnetic forces of the rotor, in a rather wide range.

For a more complete picture of the rotor of the anti-centrifugal machine, we present its design with two (Fig. 6, 7, 8a) conductors.

The calculation of the forces acting on the rotor during its rotation with a steady rotation speed (r / s) looks like this.

Here, I ₂ is the current flowing along the upper conductor of the rotor;

I _2.1 - current flowing along the lower conductor of the rotor;

F _cb.2 - centrifugal force acting on the upper conductor of the rotor and on the upper part of the centrifugally dangerous region of the rotor b ₂ ;

F _{C. b.2.1} - centrifugal force acting on the lower conductor of the rotor and on the lower part of the centrifugal hazardous area of the rotor b ₂ . _one

and - the centrifugally safe region of the rotor is limited by the hardness limit of the rotor material, at the projected rotor speed (r / s).

F _{Lor. 2} - electromagnetic containment force acting on the upper rotor conductor and due to the current strength I ₂ ;

F _Lor.2.1 - electromagnetic containment force acting on the lower conductor of the rotor and due to the current strength I _2.1

c = (D-2h ₀ ) is the distance between the two extreme conductors of the rotor;

D is the outer diameter of the rotor;

h ₀ is the height of the rotor conductor.

It must be said that in the case of the rotor design shown in FIG. 6, 7, 8, the anti-centrifugal effect of deterrence is not maximum since the distance c (m) is quite large (up to 0.5 m), and the relative magnetic permeability of the rotor material (µ) and the current density in the conductors (A / mm ² ) are limited.

The design of the rotor of the four-wire anti-centrifugal machine is shown in FIG. 9, 10, 11a.

In this case, the calculation of the forces acting on the rotor during its rotation with a steady rotation speed (r / s) looks like this (Fig. 9, 10, 11a).

Here, I ₂ is the current flowing along the extremely upper rotor conductor;

I _2.2 - current flowing along the upper conductor of the rotor;

I _2.1 - current flowing along the extremely-lower conductor of the rotor;

I _2.3 ^_ current flowing along the lower conductor of the rotor;

F _cb.2 - centrifugal force acting on the extremely upper conductor of the rotor and on the upper part of the centrifugal hazardous area of the rotor b ₂ ;

F _c.b.2.1 - centrifugal force acting on the extremely lower conductor of the rotor and on the lower part of the centrifugal hazardous area of the rotor b _2.1 ,

and - the centrifugally safe region of the rotor is limited by the hardness limit of the rotor material, at the projected rotor speed (r / s).

F _{Lor. 2} - electromagnetic containment force acting on the extreme upper conductor of the rotor and due to the current strength I ₂ ;

F _Лор2.2 - electromagnetic containment force acting on the upper conductor of the rotor and due to the current strength I _2.2 ;

F _{ENT 2.1} ^_ electromagnetic restraining force acting on the extreme lower conductor of the rotor and due to the current I _2.1

F _{ENT 2.1} - electromagnetic containment force acting on the lower conductor of the rotor and due to the current I _2.3 ;

c ₁ = (a-2h ₀ ) is the distance between the two closest rotor conductors;

a - centrifugally safe area of the rotor;

h ₀ is the height of the rotor conductor.

It should be noted that in the case of the rotor design of FIG. 9, 10, 11, the anti-centrifugal containment effect is significantly greater than in the case of two conductors of FIG. 7, 8a, because the distance c ₁ <s (m) decreases (from 0.5 m to 0.15 m), and the relative magnetic permeability of the rotor material (µ) and current density in the conductors (A / mm ² ) remain the same as in the first case.

Obviously, the rotor with additional (four) conductors of FIG. 9, 10, 11 is more effective for containing the centrifugal force in the centrifugally hazardous region of the rotor, although it is more complicated from the point of view of technological production.

The stator of the anti-centrifugal electric machine has a classical design (squirrel cage) and consists of three pairs of conductors (i.e. 6 pieces) embedded in the stator of soft magnetic material, for example, of transformer iron (Fig. 12).

The total number of conductors can be more than 6 × 2 = 12 pcs., 6 × 3 = 18 pcs., ..., depending on the diameter of the stator and its inner perimeter. Moreover, the number of stator conductors is 6 pieces - corresponds to a rotor with 2 conductors; 12 pieces - corresponds to a rotor with 4 conductors (cross); 18 pieces - corresponds to a rotor with 6 conductors (snowflake), etc.

The wiring diagram of the stator of an anti-centrifugal machine operating in generator mode is three alternating pairs of conductors connected in parallel. The ends of these conductors are brought out of the electric machine and can be connected to a three-phase network (Fig. 13), while the other ends can be connected together (into a star). In FIG. 14-17 show the operating cycles of the anticentrifugal generator, and FIG. 18 is a graph of current in its phases.

The anti-centrifugal machine operating in electric motor mode operates on the principle of repulsion of the rotor conductors from the stator (Figs. 19-25), on the rectified pulsating voltage (current) of Figs. 26 obtained by the electronic rectification unit (BEC) (Fig. 2, 27). Moreover, the starting acceleration mode of the rotor of the anti-centrifugal electric motor performs the “Electronic Acceleration Starting Block” (SBER) (Fig. 27).

The electronic rectification unit disconnects the upper half-wave of alternating current, breaking the circuit and leads the 3-phase alternating current (voltage) (Fig. 18) to the rectified ripple current (Fig. 26). Thus, it limits not only the phase current of the upper half-wave (i _Phase ), but also the induced currents in the adjacent (next) stator conductors (i _with induced) ”that arise due to the approach of the rotor conductors. Those. converts FIG. 23 in FIG. 24. The electronic rectification unit is also responsible for the rectification and proportional change of the rotor current from its rotation speed.

On the three-phase network of anti-centrifugal machines (Figs. 1, 2, 27), it must be emphasized: theoretically it works (is connected) like a modern three-phase power network, with the only difference that the frequency of such a network is greater than the traditional 50 Hz, it can be 500 Hz, 1 kHz, 10 kHz, etc. But then the peripheral speed of the anti-centrifugal electric machine with one pair of rotor conductors and 3 pairs of stator conductors will be 50 Hz = 1500 rpm; 500 Hz = 15000 rpm 1 kHz = 30000 rpm, 10 kHz = 300000 rpm. Obviously, the optimum operation of such a network lies in the range of 0.5-1 kHz.

The advantages of the new three-phase electrical system include:

1. Increased inductive resistance, which will make it possible to use the stator conductors of electric machines without extension, i.e. without additional coils and stator windings in the traditional sense.

1.1 The use of new materials with a nominally higher current density than copper.

2. All transformers and electric motors of such a network (1000 Hz and above), as well as other electrical equipment will be more compact and light at the same power.

3. When using a frequency of 1 kHz, the ability to connect conventional asynchronous motors with 8 pole pairs to such an electrical network will reduce the rotation speed from 7,500 rpm, which is quite applicable for modern electrical appliances (Figs. 1, 2, 12).

4. Applicable modern lighting load ie LED bulbs.

Also about the electric drive used in the high-frequency power network, we can say the following.

1. The anti-centrifugal motor runs on a mechanical load with a constant torque (powerful pumps, fans, etc.).

2. All other electric motors (asynchronous, DC motors) applicable in such a power supply network can operate on alternating, heavy and pulsating mechanical loads.

Claims (4)

1. The method of compensating the centrifugal force of the rotor of a reversible electric machine, which consists in restraining the magnetic field of the poles of the rotor by a restraining magnetic field, characterized in that the restraining magnetic field of the rotor is caused by the co-directional current flow in the rotor conductors located diametrically opposite, and the magnitudes of these currents are proportional to the peripheral speed of the rotor . 2. A device for compensating the centrifugal force of the rotor of a reversible electric machine, containing a stator, rotor, bearing and collector units, characterized in that it is equipped with a current regulator of the rotor of the electronic rectification unit, the stator has three alternating pairs of conductors connected in parallel and connected to a three-phase network , the rotor has at least two conductors framing the soft magnetic material of the rotor, the stator and the rotor have a number of conductors that is a multiple of two, laid in parallel. 3. The device according to p. 2, characterized in that the grooves with the conductors of the stator and rotor are evenly distributed over their surfaces. 4. The device according to p. 2, characterized in that it contains a device for measuring the peripheral speed of the rotor with a signal to the current regulator of the rotor of the electronic rectification unit.

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