RU2139622C1 - Inductor machine - Google Patents

Abstract

FIELD: electrical engineering; alternating-current machines. SUBSTANCE: according to first design version, inductor machine has rotor and stator with magnetic core made in the form of U-shaped toothed stacks uniformly arranged over circumference and forming teeth in air gap. Stator has ring winding; air gap ensures following proportion: σ_δ ≥ σ_steel,σ_steel ≤ σ_steel, where σ_δ is air-gap density; σ_steel is flux density of rotor and stator steel teeth; σ_steel is saturation flux density of steel. According to second design version, stator core of machine is made in the form of multiturn solenoid with insulated outer surface of its turns; each turn has teeth on inner surface and yokes on outer surface; stator core functions at the same time as winding. In such design of machine, areas of zero flux density are eliminated on outer surfaces of stator stacks. EFFECT: improved winding utilization factor; improved power characteristics, reduced size and mass of machine. 18 cl, 9 dwg

Description

 This proposal relates to the field of designs of AC electric machines with separated magnetic circuits.

 A device is known for an electric machine with separated phases, consisting of stator arc magnetic cores with teeth in a cylindrical gap, a rotor in the form of two symmetrically arranged hollow glasses entering cylindrical sides into the gap of the stator magnetic cores and having teeth, anchor windings covering each stator magnetic circuit and a single ring winding excitation located between the external and internal stator packets of each magnetic circuit (a.c. N 1814159 A1, M. class. H 02 K 19/06, 1993).

 The closest analogue of the claimed device is an induction electric machine containing a stator, consisting of a magnetic circuit made in the form of a burnt gear package, and at least one winding, and a rotor containing magnetic circuits. (RU, patent 2027285 C1, CL H 02 K 19/06, 1995).

 A disadvantage of the known machines is the low use of iron stator and rotor packages.

 The technical result provided by the invention is the exclusion of zones with zero induction on the outer surface of the stator and inner rotor packages and increasing the efficiency of use of the windings, thereby increasing the specific energy and weight parameters of the electric machine.

 The technical result is achieved due to two versions of the induction electric machine. The first option is an induction electric machine containing a stator, consisting of a magnetic circuit made in the form of several burnt gear packages, and at least one winding, and a rotor containing magnetic circuits, burnt gear packages are made U-shaped, evenly spaced around the circle with the formation of teeth in the air gap of the machine, and the winding is made annular in the form of an ordinary winding. The winding is located in the cavities of the U-shaped burnt packages.

 The magnetic circuits of the rotor are gear.

The air gap is
δ = (1/15 ÷ 1/22) τ,
where τ is tooth division.

The size of the air gap is made providing the following ratio:
σ _δ ≥ δ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ;
σ _steel ≤ σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ,
where σ _δ is the magnitude of the induction of the air gap,
σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ - the magnitude of the induction of saturation of steel,
σ _steel is the magnitude of the induction of the steel teeth of the rotor and stator.

 The machine is equipped with an excitation winding located on a common spool with said winding.

 The windings are made of aluminum.

 The magnetic circuit can be made single-phase or m-phase, and the U-shaped packets of adjacent phases are mounted with a shift relative to each other, and the excitation windings of all phases are connected in series.

 The rotor contains a short-circuited winding teak "squirrel cage" with straight rods.

 The rotor contains a squirrel cage winding "squirrel cage", the rods of which are transported along the length of four sections, and a pair of internal turns covers a pair of adjacent teeth of adjacent rotor cores.

 The second option is an induction electric machine containing a stator, consisting of a magnetic circuit made in the form of a lined gear package, and at least one winding, and a rotor containing magnetic circuits, in which the magnetic circuit is made of electrical steel in the form of a multi-turn solenoid, the outer surface of which turns isolated, each coil contains teeth on the inside, on the outside - a yoke, laden in the longitudinal plane, while the magnetic circuit serves as a winding at the same time.

The magnetic circuits of the rotor are gear. The air gap is
δ = (1/15 ÷ 1/22) τ,
where τ is the tooth division.

The size of the air gap is made providing the following ratio:
σ _δ ≥ σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ;
σ _steel ≤ σ $\genfrac{}{}{0ex}{}{\text{us}}{\text{become}}$ .
The rotor contains a squirrel cage winding with straight rods.

 The rotor contains a short-circuited squirrel cage type winding, the rods of which are transported over four sections in length, with a pair of internal turns covering a pair of adjacent teeth of adjacent rotor cores.

 The analysis did not reveal sources that discredit the novelty of the invention.

 When establishing the conformity of the proposal with the condition "inventive step", an induction electric machine (SU, AS 1815570 A1, class H 02 K 19/06, 1993) was identified in which the stator stacked packages are made U-shaped. However, due to the fact that in the proposed machine the U-shaped packets are installed in a different plane and, in conjunction with the ring winding, zones of zero induction on the outer surface of the stator packets and the inner rotor are excluded. Thus, the proposal meets the condition of "inventive step".

 The invention is illustrated by drawings, where in FIG. 1 shows a first embodiment of a machine with a three-phase stator (longitudinal section), FIG. 2 is a cross-sectional view A-A, in FIG. 3 is a general view of a rotor with two transported rods; FIG. 4 is a general view of a lined stator package; FIG. 5 is a connection diagram of windings; FIG. 6 is a second embodiment of a stator of an induction machine; FIG. 7 - teeth of the stator and rotor, in FIG. 8 - dependence of the limiting magnetizing force F on the angle of rotation of the rotor α, in FIG. 9 - saturation curve for steel.

 As follows from FIG. 1 motor comprises a housing 1 with stator magnetic circuits 2 and a rotor 3.

 The stator of the motor 2 includes a magnetic circuit from sets of gear packages 4-6. Each stator set consists of several U-shaped axially arranged packets (Fig. 4), forming teeth in the gap. The axes of the teeth of each stator magnetic circuit are axially located, the axes of the teeth of the phase packets are displaced relative to each other by 1/3 of the tooth division.

 Each stator package of the magnetic circuit contains an anchor winding 10-12, powered by an alternating current network or a converter, and a field winding 16-18 installed concentrically with it, all the stator field windings are connected in series and are supplied with direct current. The presence of these windings allows the machine to work in generator mode.

 The windings can be made of aluminum to reduce the weight and cost of the motor.

 The rotor 3 consists of three sets of magnetic cores 7-9, lined in radial planes, mounted on the sleeve 19 on the shaft of the rotor 20. A short-circuited squirrel cage winding is laid on the rotor, the rods 13 of which are short-circuited by rings 14 and 15 at the ends of the rotor 3.

 The rotor is made lined, round, and has a short-circuited squirrel cage winding with straight axial rods, and the teeth of adjacent packages of each magnetic circuit are shifted by half tooth division.

 The rotor winding rods (each adjacent pair of rods) can be transported along the length of 4 sections (partial turns) so that a pair of inner turns covers a pair of adjacent teeth of adjacent rotor phase magnetic circuits, while the polarity of the connection of the middle stator winding is reversed compared to the extreme ones.

 The machine can operate in motor and generator mode. Start and operation of the machine in asynchronous mode is carried out by connecting the windings to the network through closed contacts K1-K3 (Fig. 5a). To put the machine in synchronous mode, the contacts open, and it works with synchronous speed, like an inductor synchronous without excitation.

 To control the speed of the machine, the contacts K1-K3 can be replaced by controlled semiconductor devices, for example, thyristors T1-T3 (Fig. 5b), controlled from the control system unit - SU.

Сумма этих ЭДС в трех парах транспонированных витков представляет собой однофазную переменную ЭДС и ток. Взаимодействие этого тока с магнитными полями фазных магнитопроводов образует вращающий момент.In the synchronous motor mode, alternating magnetic fluxes shifted by 120 degrees are induced in each of the phase magnetic circuits. email Variable magnetic fluxes in each phase magnetic circuit induce in their pair of transported turns a variable EMF with a network frequency and amplitude, a variable angle of rotation, according to the law

The sum of these EMFs in three pairs of transposed turns represents a single-phase variable EMF and current. The interaction of this current with the magnetic fields of the phase magnetic circuits forms a torque.

 Transportation of the rods 13 along the length of the middle phase magnetic circuit requires a change in the phasing of the connection of the winding of the middle phase 11 to the network.

 To operate the machine in generator mode, it is driven by a third-party engine, the field windings are powered by direct current.

 When the rotor rotates, the magnetic flux in each phase magnetic circuit pulsates due to different magnetic resistance. The variable components of the magnetic flux induce in the armature windings a variable sinusoidal EMF shifted by 120 el. hail. in the windings of phase magnetic circuits at high rates of power quality with virtually no distortion of the harmonic voltage shape.

где τ - зубцовое деление.To improve overall dimensions, as shown by theoretical analysis, the air gap δ is selected from the condition

where τ is the tooth division.

 A second embodiment of the induction machine is shown in FIG. 6. The stator magnetic circuit in this embodiment simultaneously performs the function of a winding.

 The magnetic circuit is made of stamped plates of electrical steel in the form of a multi-turn cylindrical solenoid, each coil of which is isolated from each other, on the inside there are teeth, on the outside - back - yoke 21, the terminal turns of the magnetic circuit, lined in the longitudinal plane, connected to the network or converter.

 Combining the functions of the magnetic circuit and the winding in one device allows reducing sections by 30-32%. The stamped plates of the magnetic circuit are butt welded to form a coil.

Решение этого уравнения относительно F(α) дает кривую зависимости предельной намагничивающей силы F от угла поворота α ротора (далее ограничительной кривой). Для примера на фиг. 7 дана ограничительная кривая 1 для случая прямых зубцов машины в зазоре и индукций в стали B_ст = 1,7 Тл. График показывает, что использование этой кривой дает возможность увеличить ток двигателя и величину индукции в зазоре в 2,2 раза на участке 0^o - 30^o (зона B) (т. е. до 3,74 Тл).To improve the torque, as shown by theoretical analysis, it is advisable to have the maximum possible magnetic flux Φ = Φ _max or, more precisely, the highest possible induction in steel at the level of the knee of the saturation curve during the entire phase of the motor mode. To fulfill these requirements, it is necessary and sufficient to fulfill the condition

The solution of this equation with respect to F (α) gives a curve of the dependence of the limiting magnetizing force F on the angle of rotation α of the rotor (hereinafter the restrictive curve). For the example of FIG. 7, restrictive curve 1 is given for the case of straight teeth of the machine in the gap and inductions in steel B _st = 1.7 T. The graph shows that the use of this curve makes it possible to increase the motor current and the magnitude of induction in the gap by 2.2 times in the section 0 ^o - 30 ^o (zone B) (i.e., up to 3.74 T).

The use of chamfer A on the teeth with a leg size of ≈ 0.1 τ allows to significantly expand the zone of forced current (magnetizing force F) to 90 ^o and the amplitude of the current and induction in the gap to 8.6-fold (zone C) (t. e. up to 14.62 T).

 The use of a type 1 superconductor layer on the lateral sides of the teeth of the rotor and stator increases the amplitude of the current 1 (or F) to ≈15-17 times the magnitude of the current or induction in the gap.

Claims (17)

1. An inductor electric machine containing a stator, consisting of a magnetic circuit made in the form of several gear packets, and at least one winding, and a rotor containing magnetic circuits, gear packets are made U-shaped and evenly spaced around the circle with the formation of teeth in the air gap machine, and the winding is made annular, characterized in that the size of the air gap is made providing the following ratio:
σ _δ ≥ σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ,
σ _steel ≤ σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ,
where σ _δ is the magnitude of the induction of the air gap;
σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ - the magnitude of the induction of steel saturation;
σ _steel is the magnitude of the induction of the steel teeth of the rotor and stator.  2. The machine according to claim 1, characterized in that the winding is located in the cavities of the U-shaped charge packages.  3. The machine according to claim 1 or 2, characterized in that the magnetic circuits of the rotor are gear. 4. Machine according to any one of paragraphs.1 to 3, characterized in that the amount of air gap is
δ ≅ (1/15 ÷ 1/22) τ,
where τ is the tooth division.  5. Machine according to any one of paragraphs.1 to 4, characterized in that it is equipped with an excitation winding located on a common spool with the specified winding.  6. The machine according to claim 1 or 5, characterized in that the windings are made of aluminum.  7. The machine according to any one of claims 1 to 6, characterized in that the magnetic circuit is single-phase.  8. The machine according to any one of claims 1 to 6, characterized in that the magnetic circuit is m-phase, and the U-shaped packets of adjacent phases are mounted with a shift relative to each other by τ / m, and the excitation windings of all phases are connected in series.  9. Machine according to any one of claims 1 to 8, characterized in that the rotor contains a short-circuited squirrel cage type winding with straight rods.  10. Machine according to any one of paragraphs.1 to 8, characterized in that the rotor contains a short-circuited squirrel cage type winding, the rods of which are transported four sections in length, a pair of internal turns covering a pair of adjacent teeth of adjacent rotor cores.  11. An inductor electric machine containing a stator, consisting of a magnetic circuit made in the form of a gear package and at least one winding, and a rotor containing magnetic circuits, characterized in that the magnetic circuit is made of electrical steel in the form of a multi-turn solenoid, the outer surface of the turns of which is insulated , each coil contains teeth on the inner side, yoke on the outer side, while the magnetic core simultaneously serves as a winding.  12. The machine according to claim 11, characterized in that the magnetic circuits of the rotor are gear. 13. The machine according to claim 11 or 12, characterized in that the air gap is
δ = (1/15 ÷ 1/22) τ,
where τ is the tooth division. 14. The machine according to claim 11 or 12, characterized in that the size of the air gap is made providing the following ratio:
σ _δ ≥ δ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ ,
σ _steel ≤ σ $\genfrac{}{}{0ex}{}{\text{us.}}{\text{become}}$ .
15. Machine according to any one of paragraphs.11 to 13, characterized in that the rotor contains a short-circuited squirrel cage winding with straight rods.  16. Machine according to any one of paragraphs.11 to 13, characterized in that the rotor contains a short-circuited squirrel cage type winding, the rods of which are transported over four sections in length.  17. The machine according to any one of paragraphs.11 to 16, characterized in that the rotor contains a short-circuited squirrel cage type winding, the rods of which are transported four sections in length, with a pair of internal turns covering a pair of adjacent adjacent rotor cores.  18. Machine according to any one of paragraphs.11 to 17, characterized in that the yokes are made lined in the longitudinal plane.

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