RU2565384C2 - Dc electric machine - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention refers to electrical engineering, namely to direct-current electric machines, an armature winding of which is ring-type, whereas a magnetic core consists of laminated steel ring stacking closed to the external diameter by an outer magnetic core, provided with long non-magnetic insertions around the circumference and separated by non-magnetic annuli. An inductor magnetic core consists of laminated steel profile stacking displaced at an electric pulse angle equal to a quotient obtained when a pulse width is divided by a quantity of inductor stacking, and separated by non-magnetic annuli. Inductor winding generates a similarly polar magnetic field. An air gap with a periodically variable value is provided along the length of each polar pitch according to the law of magnetic flow transition inducing one-polar pulses of single-phase electromotive force at each polar pitch in the armature winding.

EFFECT: creating a slider-free direct-current electric machine.

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Description

The invention relates to electric DC machines and can be used both for generating direct current electric energy, and for electric drive mechanisms. Known DC collector-type machines containing an armature with a magnetic circuit and winding, an inductor with a magnetic circuit and winding and a switching device for winding the armature in the form of a collector and brush beam of a well-known design, published in monographs, such as: M.P. Kostenko, L.M. Piotrovsky. Electric cars, t.1. M .: Energy, 1964, p. 62-74; A.V. Ivanov-Smolensky. Electric cars. M .: Energy, 1980, pp. 716-717. The prototype of this technical solution adopted the design of the DC machine in the book of M.P. Kostenko, L.M. Piotrovsky. Electric cars, t.1. M .: Energy, 1964, p. 62-74. In the prototype, a direct current machine comprises an armature with a magnetic circuit and a winding, an inductor with pairwise pole divisions with a magnetic circuit and a winding, an air gap between the armature and the inductor, an armature switching device in the form of a collector with a brush beam. The disadvantage of the prototype is the presence of a sliding contact between the collector and the brush beam. The purpose of the invention is the elimination of sliding contact in a DC machine. This goal is achieved by the fact that, in contrast to the prototype, the armature winding is made of a ring type, the armature magnetic core is made of ring packages of lined steel, closed by an external diameter with an external magnetic circuit, provided with circumferential longitudinal non-magnetic inserts and separated by circular non-magnetic gaps, with an inductor magnetic circuit, made of annular steel packets, separated by annular non-magnetic gaps corresponding to the packages of the armature magnetic circuit, and with As a inductor, creating the same pole magnetic field, the air gap is made with a periodically variable value on the length of each pole division according to the law of magnetic flux variation, which ensures that unipolar pairwise impulses of a half wave emf of a sinusoidal shape are induced in the armature winding on each paired pole division, the switching device is shifted of the inductor relative to each other by the electric angle of one pulse equal to the quotient of dividing the width of one pulse by number of inductor packets.

Distinctive features of the invention are: the execution of the winding of the annular anchor; supply of the armature magnetic circuit with longitudinal non-magnetic inserts; the implementation of the inductor magnetic circuit from ring steel packets separated by annular non-magnetic gaps with the shape of its cylindrical surface, creating a change in the air gap along each pole division of the magnetic circuit, providing a law of magnetic flux change over the double pole division length, inducing unipolar pairwise pulses in the armature winding sinusoidal half-wave emf; the presence of an additional external magnetic circuit; the implementation of the packages of the magnetic circuit of the inductor with a shift relative to each other by the electric angle of one pulse equal to the quotient of dividing the width of one pulse by the number of packets of the inductor.

The proposal meets the criterion of “significant differences”, since from the well-known list of information established by the regulatory document (p. 127, E3-1-74), technical solutions with signs similar to those declared were not found. Figure 1 schematically shows a DC machine with the number of paired pole divisions equal to three (p = 3), a longitudinal section; figure 2 shows a cross section. The DC machine includes, FIG. 1 and FIG. 2, an armature with a winding 1 of ring type with a magnetic circuit, anchors from ring packages 2 of laden steel, an external magnetic circuit 3, longitudinal non-magnetic inserts 4, FIG. 2, ring non-magnetic spaces 5, inductor, FIG. .1 and FIG. 2, with a magnetic circuit made of ring packets of steel 6, with annular non-magnetic gaps 7, with a winding 8, air gap 9, FIG. 2, inductor shaft 10. The device operates in the generator mode as follows. When a current is supplied to the winding 8 of the inductor, the same-pole magnetic flux is excited in the magnetic circuits of the armature and inductor. The distribution of the magnetic flux density, Ф _α , (its induction) along the length of the pole division is practically determined by the specific value of the air gap defined by the shape of the cylindrical surface of the annular steel packs 6 of the inductor steel, i.e., the distribution of the magnetic flux along the double pole division will correspond to the inversely proportional value of the air gap

$$F_{\alpha }=F_o\frac{{\delta }_o}{{\delta }_{\alpha }}$$

where: δ _o , δ _α - the minimum and current values of the air gap along the length of the double pole arc, respectively, Ф _o - the value of the magnetic flux at the minimum value of the air gap.

When the inductor rotates, the magnetic flux in the air gap will rotate with the inductor speed and will induce the emf in the armature winding according to the expression

$${\epsilon }_{\alpha }=-C\frac{d{F}_{\alpha }}{d\alpha }$$

where Ф _α is the current value of the magnetic flux, α is the current value of the angle of the pole arc, C is a constant coefficient of proportionality. According to the expressions (Bronstein K.A., Semendyaev I.N. Handbook of mathematics, p. 555-557; Lazarev Yu. Modeling of processes and systems in MATLAB. 2005, p. 187) a general expression for the emf in the form of periodic double unidirectional sinusoidal pulses, Fig. 3, can be written in a Fourier series, which allows integration of the above expression for ε _α to obtain the desired shape and value of the flow with a given distribution along the length of the double pole arc, providing a double of the same directional sinusoidal pulse. The inductor magnetic circuit is made of ring packets shifted relative to each other by the electric angle of one pulse equal to the quotient of dividing the width of one pulse by the number of packets of the inductor. In this case, the emf will be induced along the length of one turn along the length of the armature package with a shift by the electric angle of shift of the inductor packets, and the total value of the emf over the length of one turn will be written as

$$E=\{\epsilon \max \cdot Sin{\alpha }_o+\epsilon \max \cdot Sin({\alpha }_o+\Delta \alpha )+\epsilon \max \cdot Sin({\alpha }_o+i\cdot \Delta \alpha )+\cdots +\epsilon \max \cdot Sin[{\alpha }_o+(n-i)\cdot \Delta \alpha ]\},$$

where: εmax is the amplitude of the emf along the length of one package of the anchor; α _o - the initial position of the first package of the inductor; Δα is the angle of shift between adjacent packages of the inductor; i is the number of the current inductor package; n is the number of packets of the inductor. The value of the emf in the turns of each groove of the armature winding will be almost the same. Figure 4 shows the shape of the shifted EMF pulses along the length of one turn of the armature winding.

The current has one direction in all turns of the winding around the circumference of the armature, as a result of which there is an annular magnetic flux of the armature reaction, which closes along the armature’s back, increasing saturation of the magnetic circuit of the armature’s back. To reduce the flow of the reaction of the anchor, the back of the armature is divided by longitudinal non-magnetic inserts 4, Fig.2.

The advantage of the invention in comparison with the prototype is the absence of sliding contacts.

Claims (1)

A direct current machine comprising an armature with a magnetic circuit and a winding, an inductor with pairwise pole divisions with a magnetic circuit and a winding and an air gap between them, an armature switching device of the armature, characterized in that the armature winding is made of a ring type, the armature magnetic circuit is made of ring steel packages, closed along the outer diameter by an external magnetic circuit, provided with circumferential longitudinal non-magnetic inserts and separated by annular non-magnetic gaps, with a magneto an inductor wire made of profiled ring steel packets separated by annular non-magnetic gaps corresponding to the anchor packets and to the inductor winding creating the same pole magnetic field, the air gap is made with a periodically variable value along the length of each pole division according to the law of magnetic flux change, providing induction in the winding of the armature of unipolar pulses of a single-period emf at each pole division, the switching device is made with sdv gom inductor packets relative to each other in electrical angle of one pulse is equal to the quotient of the width of one pulse to the number of packets inductor.

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