RU197319U1 - THREE-PHASE 12-ZONE ONE-TWO-LAYER STATOR WINDING - Google Patents

Abstract

The utility model relates to the field of electrical engineering, in particular, to the stator windings of three-phase AC electric machines, and can be used in their design and repair. The purpose of the utility model is to simplify manufacturing for stators with 24 slots per pair of poles (z / p = 24), 3-phase 12-zone windings with a shortened pitch y = (11/12) τ while maintaining their electromagnetic properties. The essence of the utility model: the goal is achieved in that each coil group of the 12-zone winding is made of three ontsentricheskih coils, the central coil occupies a groove and has a pitch in the grooves of y = 12, and the two outermost coils in the group occupying half of the groove are formed with steps y = 10 and 14 respectively.

Description

The utility model relates to the field of electrical engineering, in particular to the stator windings of electrical AC machines, and can be used in their design and repair.

Electric currents flowing through the three-phase stator winding of an alternating current machine create a common magnetomotive force (MDS), which in addition to the main harmonic contains a wide range of higher spatial harmonics [1, p. 441]. Higher spatial harmonics have a negative effect on the operation of the machine: braking electromagnetic moments are created, dips appear on the general characteristic of the electromagnetic moment of the induction motor, the winding inductance and power loss increase, and vibrations and noise are created [1, p. 524-531]. Therefore, when designing stator windings, they strive to reduce their manifestation.

Known two-layer m = 3-phase m'-12-zone windings with an integer q of grooves per pole and phase [2]. Three-phase 12-zone windings consist of two 3-phase windings, one of which is connected according to the "star" scheme, the other according to the "triangle" scheme. Between themselves, the parts of the winding are connected either in parallel or in series. The number of turns in the phases of the "star" w _fY and the phases of the "triangle" w _fΔ are performed according to the equality:

where k _obY and k _obΔ are winding coefficients of the “star” and “triangle”.

а сечения обмоточных проводов (S_п):

With an equal distribution of the windings of the "star" and "triangle" in the grooves, the number of turns in their phases satisfies the equality

and the cross section of the winding wires (S _p ):

As a prototype, we consider a two-layer m = 3-phase m'-12-zone winding with the number of grooves z = 48, the number of pairs of poles p = 2, pole division m = 12, a shortened pitch y = (11/12) τ and with equal the distribution of the phases of the "star" and "triangle" in the grooves. This design of the winding provides effective suppression of higher spatial harmonics. However, the implementation of a two-layer winding leads to difficulty in completing the laying of the winding in the grooves [3, p. 69-70].

The purpose of the utility model is to simplify the manufacture for stators with 24 grooves per each pair of poles (z / p = 24) of 3-phase 12-zone windings with a shortened pitch y = (11/12) τ while maintaining their electromagnetic properties.

Achieving this goal is achieved by the fact that the 12-zone stator winding has a one-two-layer design with coil groups consisting of three concentric coils, with the central coil occupying a whole groove and having a groove pitch of _k = 12, and two extreme coils in the group occupying half the groove are made with steps y _k = 10 and 14, respectively.

The essence of the utility model is illustrated in FIG. 1, FIG. 2 and FIG. 3, where:

FIG. 1a - phase distribution in the grooves of a 12-zone two-layer winding with a shortened pitch y = (11/12) τ [2] of the stator with 2p = 4, z = 48;

FIG. 1b - phase distribution in the grooves of the proposed 12-zone one-two-layer stator winding with 2p = 4, z = 48;

FIG. 2a - parallel connection of the phases of the "star" and "triangle" of the 12-zone winding;

FIG. 2b - serial connection of the phases of the "star" and "triangle" of the 12-zone winding;

FIG. 3 is a diagram of the proposed 12-zone one-two-layer stator winding with 2p = 4, z = 48.

The use of the proposed one-two-layer scheme of a 12-zone winding instead of a similar two-layer winding with a shortened pitch y = (11/12) τ improves the manufacturability by simplifying the laying of the coils in the grooves, while maintaining the electromagnetic properties, since the phase distribution in the grooves and the windings created in the gap of the MDS remain the same.

Literature:

1. Voldek A.I. Electric cars. Textbook for students of higher technical educational institutions, 2nd edition, revised. and supplemented / A.I. Voldek. - L .: Energy, 1974.- 840 p.

2. Auinger, N. Dreiphasige Wicklung in Stern-Dreieck-Mischschaltung fur eine elektrische Maschine // Patent DE 3202958. 1986.

3. Gervais G.K. Windings of electrical machines / G.K. Gervais. - L .: Energoatomizdat, 1989 .-- 400 p.

Claims (1)

Three-phase 12-zone one-two-layer stator winding of AC machines with the number of grooves per each pair of poles equal to 24 (z / p = 24), consisting of two three-phase windings offset by 30 electrical degrees, one of which is connected according to the scheme “Star”, another according to the “triangle” scheme, while the number of turns in the phases of the “star” w _fY and the phases of the “triangle” w _fΔ satisfies the equality

, and the cross section of the winding wires (S _p ):

characterized in that its coil group made of three concentric coils, the central coil occupies a groove and has slots step at _k = 12 and the two end coils in the group occupying a half of the groove are formed with steps y _k = 10 and 14 respectively.

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