RU1774436C - Alternating-current electric drive - Google Patents

Abstract

Usage: electrical engineering, electric drive for starting asynchronous single-phase electric motors without phase-shifting element. SUMMARY OF THE INVENTION: An AC electric drive comprises an asynchronous single-phase electric motor and a switching device 5 with three terminals 1.3.4. The stator of the motor has a distributed winding. At least two sections of the winding are connected in series, their ends are connected to the terminals of the switch. Upon start-up, a short-circuited section is formed. The cross section of the conductors of all sections of the winding is the same. 2 ill.

Description

FIG. 1

The invention relates to electrical engineering and can be mainly used as a single-phase asynchronous electric drive of devices and mechanisms with a fan-like nature of the load.

A known AC electric drive 1 based on an asynchronous single-phase motor containing a stator with a distributed working winding and with a high active resistance starting winding offset from it in space.

Also known is an AC electric drive 2, consisting of an asynchronous single-phase motor and a starting device. An asynchronous single-phase motor comprises a stator with a distributed winding, in which there is a shunt part, and the starting device is a switch. This device is the closest to the invention in technical essence and achieved positive effect. Its disadvantage is the relative complexity of the design.

An object of the invention is to simplify the design of an electric drive.

For this, at least two sections of the distributed stator winding of the motor are interconnected in series, their ends are connected to the extreme ends of the switching device, and the conductors of these sections have a cross section equal to the cross section of the conductors of the remaining winding sections.

Figure 1 shows the electric circuit of the stator winding of an asynchronous single-phase motor connected to a switching device, which shows a winding distributed in 2/3 of the grooves, occupying grooves 1 ... 4. 9 ... 16,

21 ... 24 and having the main conclusions 1 and 2; 3 and 4 are additional leads from sections whose magnetic axes comprise different angles with the axis of the winding (from the end of the sections located in grooves 1.9 and 2.10, respectively); 5 - switching device having contacts K1 and K2.

The structural diagram of the stator of the motor is shown in figure 2 (grooves 5 ... 8, 17 ... 20 are not stamped), where 6 is the magnetic axis of the stator winding; 7.8 - magnetic axis of the sections lying in the grooves of 2.10 and 1.9, respectively. Axes 7 and 8 form with the axis 6 spatial angles cpr1 and Opr2.

Claims (1)

The claims AC electric drive, including an asynchronous single-phase electric motor, in the grooves of which a distributed winding is placed, made of connected electric and sections shifted in space, and a switching device having three terminals to which at least two sections of the winding are connected, characterized in that which, in order to simplify the design, the latter are interconnected in series, their ends are connected to the extreme terminals of the switching device, and the middle point is connected to the middle terminal of the switching device, and the conductors of these sections have a cross section equal to the cross section of the conductors of the remaining sections of the winding. Fig, 2.