SU1377972A1 - Arrangement for starting induction motor with phase-wound rotor - Google Patents

Abstract

The invention relates to electrical engineering, namely, devices for starting induction motors with a phase rotor. The object of the invention is to reduce the overall dimensions of a device for starting an asynchronous motor with a phase-rotor. The device contains a massive ferromagnetic magnetic core, made in the form of a six-core core 1 with a symmetrical arrangement of the rods and an annular frame 2, connecting all the rods from the ends. Windings 3-8 are located on the rods. Additional windings 9-14 are located on ring yoke 2. Series-connected windings 9,3,6,12} 11,5, 8,14; 13,7,4,10 are groups of windings, forming phases A, B, C, respectively. Conclusions 15,16,17 of these groups are intended for connection to the rotor windings of the engine. The starting device is placed on the shaft 18. 1 Il. Q 9 (L

Description

with

with

The invention relates to electrical engineering, namely to devices for starting induction motors with a phase-rotor,

The purpose of the invention is to reduce the size of the device.

The drawing shows the design of the device.

The device contains a massive ferromagnetic magnetic core, made in the form of a six-core tsiderka 1, an annular frame 2 connecting the rods from the ends, windings 3-8, located on the cores of the core 1, additional windings 9-14, located on the ring frame 2 The series-connected windings 9,3,6,12,11,5,8,14 ", 13,7,4, 10 are groups of windings that form phases A, B, C, respectively. The terminals 15-17 of the group are intended for connection to the rotor windings of the engine and are connected to a common point. The device can be placed on the shaft 18 of the induction motor. The beginning of each winding is indicated by a dot in the drawing.

The device works in the following way.

At the time of starting the AC motor, three-phase rotor voltage is applied to the outputs of 15-17 groups of the rotor and current flows through them. In the drawing, solid arrows show the direction of flow during the flow of a linear current, dashed r arrows, the direction of flow during the flow of a linear current

The magnetic system of the device is symmetrical. When an alternating current flows through any winding, an alternating magnetic flux will flow through the magnet wire on which this winding is located, closing through the corresponding cores of core 1 and part of the ring rail 2.

Loss due to hysteresis and eddy currents occur in the massive ferromagnetic magnet topow. During engine acceleration, the voltage decreases, the current and frequency in the rotor decrease, the magnetic flux and eddy current in the device magnetic circuit decrease, the resistance of the device decreases, which ensures a smooth start of the engine.

In this device, the magnetic circuit is composed of ferromagnetic elements with windings through which alternating current flows. The absence of sections of a large magnetic circuit with large magnetic co - f. Resistance without windings with a current allows to reduce the scattered fluxes, to increase the magnetic induction value elements of a massive ferromagnetic magnetic core and, as a result, reduce the size of the device for a given resistance of its windings.

Claims (1)

Invention Formula A device for starting an asynchronous motor with a phase rotor, containing a massive ferromagnetic magnetic circuit. Executed as a multi-core core mounted on a shaft with a symmetrical arrangement of the rods and windings on them and cooling the core / its frame, characterized in that, in order to reduce the size of the device, the core made six-rod, and the RMO - ring, on the sections of the frame, located between adjacent rods, there are additional windings, some of which are located on the sections of the frame, not ykayuschih coaxial to the rods, is connected to the windings arranged on them in series to form winding phase groups.