SU1295495A1 - Two-motor electric drive - Google Patents

Abstract

The invention relates to electrical engineering and can be used in electric drives of general industrial mechanisms. The aim of the invention is to increase reliability. This goal is achieved by switching on the switching elements 11-14 between the terminals of the phases of the stator windings 2 and 3 of the electric motors, which makes it possible to exclude six diodes 4-9 from the operating mode of the electric motors. This increases the reliability of the device and eliminates the asymmetry of fuses for motors, thereby increasing the energy performance of the latter, and the resistor 10 between the cathode and anode valve groups of the device limits the maximum allowed braking current, which increases reliability device operation and allows you to set the required braking performance. I il. i (l con

Description

The invention relates to electrical engineering and can be used in electric drives of conventional mechanisms.

The purpose of the invention is to increase reliability.

The drawing shows a schematic diagram of a twin-motor drive.

The electric drive contains two asynchronous electric motors, contacts 1 of a linear contactor, some of the outputs of which are provided with leads for connection to the power source, and others with some of the single phase stator windings 2 and 3 of the electric motors combined, the other phases of the stator winding 2 of the first electric motor are connected to cathodes of the first three diodes 4-6, the other phases of the stator winding 3 of the second electric motor are connected to the anodes of the second three diodes 7-9, the cathodes of which are combined and are connected to common point through resistor 10 united anodes of diodes 4-6, other outputs of the first phases of the stator syncope of each electric motor through the first and second switching elements 11 and 12, respectively, are connected to other higher stages of the second phases of their electric motor, which are connected to other third phases of the third and fourth switching elements stator windings of each electric motor.

The device works as follows.

When the motors are turned on, the contacts 1 of the linear contactor and simultaneously the switching elements 11-14 are closed, while the switching elements 11 and 13 connect the ends of the stator winding 2 of the electric motor to a common point, and the switching elements 12 and 14 connect the ends of the stator winding 3 of the electric motor to a common point .

The stator windings of each electric motor are flowed around by an alternating current, as a result of which a rotating magnetic field occurs, under the action of which the rotor of the engine begins to rotate. At the same time, the switching elements 11 and 13 shunts diodes 4-6, and the switching elements 12 and 14 diodes 7-9.

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The braking mode is realized by simultaneously opening the switching elements 11 - 14. In this case, the windings 2 and 3 of the electric motors flow around the half-full TokoM network, which is closed through the resistor 10, and also by the current of the EMF of the electromagnetic induction due to the presence of three short-circuited loops, which also closes through resistor 10. The motors are effectively braked, and the required braking performance can be set by changing the value of the resistor 10. With the help of this same resistor, the necessary the level of the maximum allowable braking current, which also increases the reliability of the device.

Motor deceleration mode is terminated when the contacts 1 of the line contactor are disconnected.

The invention makes it possible to exclude six diodes from the operating mode of the motors, which increases the reliability of the device and eliminates the asymmetry of the phase voltages for the motors, thereby increasing the energy performance of the latter.

The presence of a resistor between the cathode and anode group of the device valves provides for limiting the maximum permissible braking current at the required level, which also increases the reliability of the device and allows the required braking efficiency to be established.

Claims (1)

Invention Formula A two-motor electric drive containing two asynchronous electric motors, contacts of a linear contactor, some of the outputs of which are equipped with outputs for connection to a power source, while others are connected to one terminals of the single-phase stator windings of the electric motors, other terminals of the stator windings of the first electric motor are connected to the cathodes of the first three diodes the anodes of which are combined, the other phase terminals of the stator winding of the second electric motor are connected to the anodes of the second three diodes, the cathodes of which are combined us, three switching element different 312954954 By the fact that, in order to increase the reliability of its electric motor, which are four, the fourth commutator, the third and fourth commutation element and the resistor, are introduced into it, the other elements, respectively, are connected to the first phase phases of the stator windings by other motors of the third phase of the stator; - the windings of each electric motor, the second and the second switching elements, the common output of the anodes of the first three diodes, respectively, are connected to others through a resistor connected to the common outputs of the second phases of the stator windings gaodom second three cathodes of diodes.