RU2110879C1 - High-speed electric motor - Google Patents

Abstract

FIELD: miscellaneous electric drives. SUBSTANCE: rotor is prefabricated and pre-balanced part that has permanent magnets whose central end portions are joined by means of laminations with hub. EFFECT: simplified design, reduced mass. 2 dwg

Description

 The invention relates to electrical engineering, in particular to drives with an electric motor.

 The brushless asynchronous three-phase squirrel-cage electric motors are widely known and most common. An asynchronous electric motor is excited by alternating current, which, as a rule, is supplied to the electric motor from an alternating current network having an industrial frequency of 50 Hz [1].

 Known AC electric motor containing a stator with a winding, a rotor with a short-circuited winding, made in the form of a squirrel cage, and a shaft with bearing bearings (see ed. St. USSR N 1053229, class. H 02 K 17/00, 1983).

 To control the rotational speed of an induction motor with a phase rotor, devices containing a frequency converter with direct coupling in the rotor circuit can be used [2]. These devices have significant dimensions and weight.

 The closest analogue of the invention is an electric motor comprising a rotor rotating around an axis and a stator mounted coaxially with the rotor. Around the circumference of the rotor and stator are several bipolar poles. The rotor poles are located inside, and the stator - outside the circle, the concentric axis of the rotor and lying in a plane perpendicular to this axis. A block connected to one of the groups of poles controls the supply of power to it to selectively magnetize the poles and create a rotating magnetic field. Each of the poles of the rotor has a magnetic core of an E-shaped cross section, and the plane of the cross section is perpendicular to the plane of the circle on which the poles are placed. The open part of the cores faces this circle and has one central and two external protrusions. At each pole of the rotor around the central protrusion is wound at least one coil connected to the control unit to create a rotating magnetic field [3]. This electric motor does not allow to obtain high speeds and is difficult to manufacture, since it is difficult to balance it and perform an electronic device of the control unit to create a rotating magnetic field.

 The aim of the invention is the creation of a high-speed engine with speeds up to 50,000 per minute, having a simple design and low weight.

 The specified technical result is achieved in that the rotor is made in the form of a pre-mounted and balanced assembly that includes a sleeve and at least two permanent magnets uniformly spaced across the cross section, the central parts of the ends of which are connected via plates to the sleeve, the latter being pressed onto the power take-off shaft, at In this case, the adjacent magnets are oppositely magnetized and their longitudinal size is larger than the inner radius of the stator, and the electronic device is made in the form of of the connections between a diode bridge, a filter and a thyristor converter.

 Figure 1 schematically shows a longitudinal section of a high-speed electric motor; figure 2 is a cross section aa in figure 1.

 The high-speed electric motor contains: a stator 1 having windings 2, a rotor 3 mounted in bearing bearings 4, a power take-off shaft 5 with a sleeve 6 pressed on it, connected by means of plates 7 to the central parts of the ends of the permanent magnets 8 located with a gap relative to the stator 1, moreover, the adjacent magnets are oppositely magnetized and their longitudinal size is larger than the inner radius of the stator, and the electronic device for creating a rotating magnetic field (not shown) is made in the form of a series connection ennyh between a diode bridge (type D-245 or D-246), a filter (RC type) and a thyristor converter. The gap between the stator 1 and rotor 3 is of the order of 2 mm, an increase in the gap leads to a loss of power. It is desirable to use magnets 8 on a ceramic basis, which avoids the appearance of dust and will increase the working life. Magnets 8 can be made in the form of strips curved along cylindrical generators (as shown in Fig. 2), and the cross section can be round or rectangular.

 To ensure the operability of the electric motor at revolutions of 50,000 per minute, the rotor 3 is pre-assembled and balanced by drilling its elements or by installing balancing weights (not shown), which avoids vibration during operation and destruction of bearing bearings 4, as well as ensures a constant gap between the stator 1 and rotor 3.

 The proposed high-speed electric motor operates as follows. The current in the windings 2 of the stator 1 is supplied from the AC network through a diode bridge, a filter and a thyristor converter connected in series, which allows you to create a rotating magnetic field and adjust the angular speed (revolutions) of the rotor 3 of the electric motor due to the interaction of the magnetic fields of stator 1 and magnets 8 rotor 3, while the adjacent magnets 8 are oppositely magnetized in the rotor 3.

Claims (1)

 A high-speed electric motor, comprising a rotor rotating around an axis and a stator mounted coaxially with the rotor, an electronic device for creating a rotating magnetic field connected to a current source, and a power take-off shaft installed in the bearing supports of the stator housing, characterized in that the rotor is preformed a mounted and balanced assembly comprising a sleeve and at least two permanent magnets uniformly spaced across the cross section, the central parts of the ends of which are are united by plates with a sleeve, the latter is pressed onto the power take-off shaft, while the adjacent magnets are oppositely magnetized and their longitudinal size is larger than the stator's inner radius, and the electronic device is made in the form of a diode bridge, a filter, and a thyristor converter connected in series.

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