RU2359392C1 - Commutator machine with polar armature - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: present invention relates to electrical engineering and design of dc and ac commutator machines, as well as universal commutator motors. The commutator machine with a polar armature contains a field pole, an armature with uniformly spaced out poles, commutator, brush-connector assembly unit mechanism with brushes, closed drum winding of the armature made from coils, each of which is on the corresponding pole of the armature and contains one or several sections, consisting of one or several windings. This electric machine can be used as a generator and dc motor with independent excitation by permanent magnets and from independent excitation winding, with parallel, series and compound excitation, as universal commutator motors and as ac motors with series excitation. It is necessary to meet defined ratios between the number of field poles and number of armature poles, as well as field poles and armature poles with defined width of polar arc, and brushes and commutator bars with defined width.

EFFECT: provision for improved energy characteristics and improved commutation of commutator machines with a polar armature with simplification of the design as the same time and high reliability, as well as possibility of using the electric machine at low and high voltages.

12 cl, 6 dwg

Description

The invention relates to the field of electrical engineering and for the design of collector electric DC machines, universal collector electric motors, collector electric machines of alternating current and can be used in all sectors of the economy.

Known collector electric machines with closed drum windings of the anchor (Petrov GN Electric machines. In 3 hours. Part 3. Collector machines of direct and alternating current. Ed. 2 nd, revised, and add. - M., " Energy ”, 1968. Pages 9, 15-35, 194-202), formed from series-connected sections, each of which is connected to the corresponding collector plate. A section consists of one or more turns. One or more sections having common insulation form a coil of the winding, which fits into the grooves and covers several teeth of the armature. The total number of collector plates is equal to the total number of winding sections. Depending on the method of connecting the sections to the collector plates, the anchor windings are divided into loop, wave and combined. A disadvantage of the described electrical machines is the structural complexity of the armature winding, which is performed by coils distributed over the surface of the armature, covering several teeth of the armature and intersecting each other in the frontal parts, which reduces the reliability of these windings. In addition, medium and large collector electric machines are made with additional poles, which also complicates their design.

Known designs of collector electric DC machines manufactured by Thomson-Gusten, having three-section ring windings, winding sections are connected to a star like a multiphase (three-phase) winding and are connected to three collector plates (DC machines. Volume 1. E. Arnold, prof. and I.L. La-Kur. State Technical Publishing House. M., 1931. P. 21-23). The disadvantage of such electric machines is the difficulty of performing an annular armature and an annular winding, low energy performance, and due to the fact that the armature winding is open, sparking is inevitable during switching due to the large self-induction of the sections.

The design of an electric Gerard machine with a pole anchor (DC Machines. Volume 1. E. Arnold, prof. And I.L. La-Cour. State Technical Publishing House. M., 1931. Pages 22-23), having an inductor with four poles, an anchor with four poles, each of which has its own coil of the winding, four collector plates connected in pairs through one, and two brushes located between the poles of the inductor and at an angle of 90 ° relative to each other, the coil of the armature winding are interconnected according to the beginning of the first and The end of the fourth coil is connected to two corresponding plates located along the axis of the poles of the armature. The disadvantage of such electric machines is the large ripple of the moment when working as an electric motor and the large ripple of the output voltage when working as an electric generator, low energy performance, and due to the fact that the armature winding is open, sparking during switching due to the large self-induction of the coils is inevitable .

The design of an electric machine for feeding arc lamps of an electric company Westinghouse is known, having 6 excitation poles, two collectors, four brushes, 8 armature poles, each pole of which has its own section of the winding (DC machines. Volume 1. E. Arnold, prof. And I.L. La-Chur. State Technical Publishing House. M., 1931. P. 23). The armature winding is made in the form of odd and even sections, forming two independent winding systems, each of which is connected to its collector. The second and third brushes are shorted to each other, connecting both winding systems in series. The first and second brushes are used to relieve voltage in generator mode. The disadvantage of such electric machines is the design complexity due to the presence of two collectors, a large output voltage ripple when operating with an electric generator, and due to the fact that the armature winding is open, sparking is inevitable during switching due to the large self-induction of the sections.

Known for the prototype design of a collector electric machine with a pole anchor from Schuckert and Co., the winding of the armature of which is similar to a three-phase winding and made by coils located on a triple T-shaped armature, the poles of which are shifted relative to each other by 120 °, the ends of the winding are connected into a “star”, and the beginning of the winding is connected to three collector plates, on which two brushes slide (DC machines. Volume 1. E. Arnold, prof. and I. L. La-Kur. State Technical Publishing House. M., 1931 . Pp. 22-23). The disadvantage of the prototype is the poor use of the useful volume of the electric machine, which negatively affects energy performance, and due to the fact that the armature winding is open and each armature winding coil consists of only one section, sparking is inevitable during switching due to the large self-induction of the coils, and for this reason, the use of these electrical machines is only possible at low voltages.

The aim of the present invention is to improve the energy performance of a collector electric machine with a pole armature, improve switching, the possibility of using both low and high voltages. This goal in accordance with the present invention is achieved through a more rational use of the useful volume of the electric machine, the use of a closed winding of the armature, consisting of coils, each of which is located on the corresponding pole of the armature and contains one or more sections consisting of one or more turns, and connected in a certain way to the collector.

It should be noted that in the electric machines proposed in the present invention, as in most classical collector electric machines for direct and alternating current, the magnetic flux of the excitation is created by the winding or permanent magnets of the inductor, and the armature winding is placed in the grooves of the armature core. Most often, the inductor is a stator, and the anchor is a rotor. However, for a number of applications it is possible to use an inductor as a rotor, and anchors as a stator, or an anchor and inductor as rotors rotating relative to each other.

The invention consists in the following. A collector electric machine with a pole anchor (Fig. 1, Fig. 2) consists of the following main parts: a stator, an armature with a mechanical collector, a brush-contact assembly, and bearing shields. The stator consists of a metal housing 1 made of soft magnetic material (steel), to which the excitation poles are attached 2. For DC electric machines, the excitation poles 2 can be formed directly by permanent magnets 3, magnetized in the radial direction and attached to the housing 1 (Fig. 3), can be made by metal processing of solid pieces of steel with high magnetic permeability, can be made of steel with high magnetic permeability and have pole cores and the pole pieces attached to them, for the purpose of manufacturability, can be made from batches of electrical steel sheets and attached directly to the housing 1. For low-power electric DC machines, for the purpose of manufacturability, the stator can be made in the form of a burst bag 4, assembled from sheets of electrical steel, having an excitation pole 2, and to be unpacked, as well as a burnt package 4 can be fixed inside the housing 1 (figure 4). For universal collector motors and AC collector machines, in order to reduce hysteresis and eddy current losses, the stator should be in the form of a charge package 4, composed of sheets of electrical steel having excitation poles 2, and can be unpacked, as well as a charge package 4 can be fixed inside the housing 1 (figure 4).

In accordance with the present invention, the number of excitation poles z _B must always be an even natural number, the width of the pole arc b _{ZB of the} excitation pole is associated with the pole division t _ZB of the excitation poles and is determined in accordance with the expression

where b _ZB and t _ZB = 360 ° / z _B are measured in geometric degrees. For better utilization of the net volume of an electric machine, it is desirable to select b _ZB close to t _ZB .

At the poles of the excitation of an electric machine (except electric machines with permanent magnets) is an excitation winding, consisting of coils 5 made of insulated copper wires or insulated copper busbars. The field winding coils 5 are interconnected so that, when current flows through them, the field poles form an alternating magnetic polarity “N” and “S” in the air gap. When performing DC collector electric machines with permanent magnets, the alternating polarity “N” and “S” of the excitation poles must also be observed in the air gap.

The core of the armature in order to reduce losses on hysteresis and "eddy" currents is made in the form of a burnt bag 6, composed of sheets of electrical steel having grooves into which the armature winding is laid, and the pole of the armature 7 (figure 4). The width of the pole arc b _{Z Z of the} pole of the armature is related to the pole division t _{ZB of the} pole of the armature by the expression

where b _ZЯ and t _ZЯ = 360 ° / z _I are measured in degrees. For the best use of the useful volume of the electric machine, it is desirable to choose b _ZЯ close to t _ZЯ .

In accordance with the present invention, between the number of poles of the armature z _I and the number of poles of excitation z _B a connection is established

where R = 1, 2, 3, 4 ... is a natural number.

A closed winding of the armature, consisting of coils 8, each of which is located on the corresponding pole of the armature 7 and contains one or more sections 9 (figure 5), made of insulated copper wires or insulated copper busbars. The total number of sections of the armature winding of an electric machine is equal to the product of all coils of the armature winding by the number of sections in one coil. Sections 9 consist of one or several turns and are connected to each other in a sequential closed circuit so that the ends of the previous sections are connected, together with the beginnings of subsequent sections, to the corresponding collector plates 10 of the collector 11. The collector plates when making the coil windings of the multi-section armature can have different widths (wide and narrow plates). The total number of collector plates (wide and narrow) is equal to the total number of sections of the armature winding. With the aim of manufacturability of the collector, wide plates can be formed using copper jumpers 12, which are conveniently made from the same wires as the sections, while performing all the collector plates of the same width (Fig.6).

The charge package 6 of the core of the armature, the collector 11 and bearings 13 are pressed onto the shaft 14, which is made of steel, and using the bearing shields 15 the armature is positioned relative to the stator.

The mechanism of the brush-contact assembly is most often attached to the bearing shield from the side of the collector and may be able to move the brushes 16 along the collector in the tangential direction to install the brushes in the area with the best commutation. The brushes should be installed along the axis of the excitation poles in the axial direction or close to it. The number of traverse brush bolts on which the brush holders with brushes are mounted is equal to the number of machine excitation poles. Several brushes may be located on the brush bolt, but the number of brushes on each brush bolt should be the same. Switching in the switched section should take place at that time when the change in the magnetic flux created by the excitation poles and penetrating the pole of the armature on which the switched section is located is minimal and is caused only by the action of the "reaction" of the armature. The width of the switching zone b _KZ should not exceed the difference between the width of the pole arc of the excitation pole and the width of the pole arc of the pole of the armature, i.e.:

where b _SC , b _ZB , b _ZЯ are measured in geometric degrees. The width of the collector plates depends on the total number of sections of the armature winding, the width of the switching zone and the width of the brush.

A DC collector electric machine with a pole armature can be made with independent excitation from permanent magnets, with independent excitation when supplying the field winding from an independent DC voltage source, with series excitation when the field winding is connected in series with the armature winding, with parallel excitation when the winding is connected in parallel excitation with armature winding, with mixed excitation in the presence of two field windings, one of which is connected and with the armature winding in series, and the other - in parallel.

A DC collector electric machine with a pole armature can be designed as a universal collector electric motor with a pole armature, the field winding of which is a winding with a different number of turns for power supply from a DC voltage source and from an AC voltage source. When the electric motor is supplied with constant voltage with the armature winding, the excitation winding with the total number of turns is connected in series through the brushes of the same name and sliding contacts, and when the electric motor is supplied with alternating voltage with the armature winding, the excitation winding with a small number of turns is connected in series through the brushes and sliding contacts.

An alternating current collector electric machine with a pole armature can be used as a series excitation motor, while the field winding is connected at one end to an alternating voltage source and the other end is connected in series with the armature winding through the same brush and sliding contacts.

DC collector electric machines with pole anchors are reversible and can operate both as electric motors and as electric generators.

Let us consider the operation of the proposed electric machines using the example of a DC electric motor with two excitation poles, three armature poles, an independent field coil, four sections in a coil of a closed armature winding, with two brushes and with a collector containing thirty collector plates of the same width (Fig. .6). For clarity, the field poles with the field coil and the bed are shown in the expanded form in the axial direction, and the pole of the armature with the coil of the armature and the collector plates are shown in the expanded form in the radial direction. The direction of the current flowing through the excitation coils is shown "from us" by a cross, "to us" by a dot. The direction of the currents flowing through the sections of the armature is shown by arrows. The plus and minus brushes are shown with plus and minus signs. The direction of the electromagnetic moment acting on the armature of the electric motor is shown by an arrow with the letter M.

A voltage is supplied from the independent DC voltage source to the field coils 5, a direct current flows through the coil, as a result of which the field poles 2 are magnetized, forming "north" poles "N" and "south" poles "S" with alternating magnetic polarity. A voltage is applied to the brushes 16 from another independent source of constant voltage, under the influence of which direct current flows through the sliding contacts and collector plates 10 through sections P of the closed armature winding, magnetizing the poles of the armature 7 either as “north” poles “N”, then as “south” "S" poles, depending on the position of the poles of the armature relative to the brushes. In sections of the winding of the armature, shorted by brushes, switching occurs. The "north" poles of the "N" anchor tend to push out from under the "north" poles of the "N" excitation and get pulled under the "south" poles of the "S" excitation, while the "south" poles of the "S" anchor tend to push out from under "South" poles of the "S" field and get drawn under the "north" poles of the "N" field, thereby creating an electromagnetic moment acting on the stator and the armature of the electric motor. When moving the anchor one pole, the picture repeats.

The technical result of the present invention is improved energy performance of a collector electric machine with a pole armature, improved switching, the use of electric machines at both low and high voltages, simplicity of design, high reliability.

Prototypes of collector electric machines with pole anchors and a closed drum winding of the armature were made and investigated by the author on the basis of classical collector electric machines of direct and alternating current. For this purpose, the windings of the anchors were rewound and studies of an electric motor of direct current with independent excitation of type 2PB 100 MUH L4 were carried out while feeding the excitation winding from a source of constant voltage 220 V and the armature winding from a source of constant voltage 60 V, electric motor of direct current with parallel excitation of the type SL-621 when powered by a 110 V DC source, DTA-40 universal collector electric motor when powered by a 85 V DC source and from a source of alternating voltage of 95 V, electric motors of alternating current with series excitation used in domestic vacuum cleaners, when powered from an alternating current network with a frequency of 50 Hz and a voltage of 220 V at various ratios of excitation poles and armature poles, as well as for different numbers of sections of the armature winding . Compared to the basic design, prototypes showed rather high energy parameters, good switching and very high reliability of the armature windings, the current density in which reached up to 15 A / mm ² during research.

Claims (12)

1. A collector electric machine with a pole anchor, comprising excitation poles, an armature with poles uniformly shifted relative to each other, a collector with collector plates of the same width and adjacent brushes, the armature winding of which is made by coils, each of which is located on the corresponding pole of the armature, and the beginning of each coil of the armature winding is connected to the corresponding collector plate, characterized in that, in order to better use the usable volume and improve energy performance of the electric machine, the width of the pole arc b _{ZB of the} excitation pole is related to the pole division of t _ZB of the excitation poles and is determined by the expression 2 / 3t _ZB ≤b _ZB <t _ZB , where b _ZB and t _ZB = 360 ° / z _B are measured in geometric degrees, the width of the pole arc b _{ZЯ of the} armature pole is related to the pole division t _ZЯ of the armature poles by the expression b _ZЯ <t _ZЯ , where b _ZЯ and t _ZЯ = 360 ° / z _I are measured in geometric degrees, while the number of excitation poles z _{B is} always an even natural number and between the number of poles of the armature z _I and the number of poles of excitation z _B the connection is established z _I = z _B + R, where R = 1,2, 3.4 ... is a natural number, in order to improve switching and use of electric machines at both low and high voltages, the armature winding is closed and consists of coils, each of which is located on the corresponding pole of the armature and contains one or more sections, the total the number of sections of the armature winding of an electric machine is equal to the product of all coils of the armature winding by the number of sections in one coil, the sections consist of one or more turns and are connected to each other in a series closed circuit in this way that the ends of the previous sections are connected together with the beginnings of subsequent sections to the respective collector plates of the collector, the number of collector plates is equal to the total number of sections of the armature winding, the brushes are installed along the axis of the excitation poles in the axial direction or close to it, the number of brush bolts of the traverse is equal to the number of electric excitation poles machines, the width of the switching zone b _KZ is subject to the expression b _KZ <b _ZB -b _ZЯ , where b _KZ , b _ZB , b _ZЯ are measured in geometric degrees. 2. A collector electric machine with a pole anchor according to claim 1, characterized in that the excitation of the electric machine is carried out using an independent field winding, which is located on the field poles and connected to an independent source of constant voltage. 3. A collector electric machine with a pole anchor according to claim 1, characterized in that the excitation of the electric machine is carried out using permanent magnets. 4. A collector electric machine with a pole anchor according to claim 1, characterized in that the excitation of the electric motor is carried out using a series excitation winding, which is located on the excitation poles and connected at one end to a constant voltage source, and the other end through brushes and sliding contacts of the same name connected in series with the armature winding. 5. A collector electric machine with a pole anchor according to claim 1, characterized in that the excitation of the electric machine is carried out using a parallel excitation winding, which is located on the excitation poles and connected in parallel to a constant voltage source and connected through unlike brushes and sliding contacts in parallel with the winding anchors. 6. A collector electric machine with a pole anchor according to claim 1, characterized in that the excitation of the electric machine is carried out using a mixed field winding, which is located on the field poles and consists of series and parallel windings, a series winding through the same brush and sliding contacts at one end connected in series with the armature winding, and the other end connected to a constant voltage source, parallel winding through unlike brushes and sliding contacts It is connected in parallel with the armature winding and is connected in parallel to a constant voltage source. 7. A collector electric machine with a pole anchor according to claim 1, characterized in that it is designed to operate as a universal collector electric motor, the excitation of which is carried out using an excitation winding, the excitation winding is located on the excitation poles and is a winding with a different number of turns for power from a constant voltage source and from an alternating voltage source, when feeding an electric motor with constant voltage with an armature winding in series Res same name and the brush sliding contacts connected to the excitation winding with a complete number of turns, and for feeding the electric motor with the AC voltage across the armature winding in series with the same name and the brush sliding contacts connected to the excitation winding with a small number of turns. 8. A collector electric machine with a pole anchor according to claim 1, characterized in that it is designed to operate as an alternating current electric motor, the excitation of which is carried out using a series excitation winding, the excitation winding is located on the excitation poles and is connected at one end to an alternating source voltage, and the other end through the same brush and sliding contacts connected in series with the armature winding. 9. A collector electric machine with a pole anchor according to claim 1, characterized in that the armature is located outside and rotates, the inductor is located inside and stationary. 10. A collector electric machine with a pole anchor according to claim 1, characterized in that the anchor is located inside and stationary, the inductor is located outside and rotates together. 11. A collector electric machine with a pole anchor according to claim 1, characterized in that the armature is located inside, the inductor is located outside, the armature and inductor rotate relative to each other and relative to the stator. 12. A collector electric machine with a pole anchor according to claim 1, characterized in that the armature is located outside, the inductor is located inside, the armature and inductor rotate relative to each other and relative to the stator.

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