SU1310986A2 - Two-motor electric drive - Google Patents

Abstract

The invention relates to electrical engineering, can be used in electric drives made according to an electric shaft system, and is in addition to the author. St. No. 1176436. The purpose of the invention is to increase the reliability of the device. The goal is achieved by introducing into the circuit of a single phase of the stator winding of electric motors 1 and 2 parallel to the contacts of a linear contactor 31 and 32 of a light-voltage circuit consisting of a series-connected thyristor 19 and a current limiting resistor 21 and a thyristor 20 and a resistor 22, respectively. The inclusion of thyristors 19 and 20 in the dynamic braking modes is provided by means of charged piaHee capacitors 10 and 11, respectively, through the closing contacts 25 and 26 of the brake contactor. I il. € (L with CX O5 1H

Description

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. The invention relates to electrical engineering, can be used in electric drives made by an electric shaft system, and is in addition to the author. St. No. 1176436.

The aim of the invention is to increase the reliability of the device.

In the drawing is a schematic diagram of a twin-motor drive.

The device contains two asynchronous electric motors 1 and 2 with a phase rotor, two three-phase bridge rectifiers 3 and 4, the connection points of the anodes of the valves of the first n of the second three-phase bridge rectifiers 3 and 4 are combined and connected to the first output of the first resistor 5, two three-phase throttles 6 and 7 saturation with the main winding 8 and the three-section control winding 9, each section of which is located on the corresponding core of the throttle magnetic circuit 6 and 7 saturation, two capacitors 10 and 11, seven diodes 12-18, two thyristors 19-20, four resis Speakers 21-24, brake contactor with six closing contacts 25-30, two linear contactor 31 and 32 with three closing contacts each, through which the stator windings of induction motors 1 and 2, respectively, are connected to the mains, three sections of the winding 9 of the first throttles are 6 ; e- are connected in series with the three sections of the winding 9 of the second droplets 7 of saturation; the first diode 12 and the first capacitor 10 are connected in series bypass three sections of the winding 9 of the first saturation drops 6, the second diode are connected in series 13 and the second capacitor I1 shunt three sections of the winding 9 of the second throttle 7 saturation. The main winding 8 of the first saturation throttle 6 is connected between the leads of the rotor winding of the first asynchronous motor I and the input of the first three-phase bridge rectifier 3, the main winding 2 of the second throttle of saturation 7 is connected between the leads of the rotary winding of the second asynchronous motor 2 and the input of the second three-phase bridge rectifier 4, the connection point of one output of the three-section winding 9 of the control of the first throttle 6 and the anode of the first diode 12 is connected to the connection point of the cathodes of the valves

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the second three-phase bridge rectifier 4, points of connection of one output of the three-section winding 9 control the second three-phase throttle 7

J and the anode of the second diode 13 are connected to the connection point of the cathodes of the valves of the first three-phase bridge rectifier 3, the connection point of the other output of the three-section winding 9 of the first three-phase droplet 6 of the saturation and the output of the first capacitor 10 is connected to the connection point of the other output of the three section winding 9 control the second three-phase depressor 7 of the end and the second capacitor 1I and to the connection point of another pin of the resistor 5 with the cathode of the third diode 14, the anode of which is connected to the first pin

0 of the resistor 5, the anodes of the first 19 and second 20 thyristors are connected to the first and third phases of the supply circuit, respectively, and the cathodes of these thyristors are connected to the first terminals of the second 21 and third 22 resistors, respectively, the first 12 and second diodes of the 13 diodes, respectively, through the first 25 and the second 26 closing contacts of the brake contactor are connected respectively to the third phase of the stator winding of the first asynchronous electric motor 1 and to the first phase of the stator winding of the second electric motor 2 through a series This fourth resistor 23, the control electrode of the first

a thyristor 19 and a second resistor 21 and a series-connected fifth resistor 24 controlling the electrode

0 of the second thyristor 20 and the third resistor 22, the cathodes of the fourth 15 and fifth 16 diodes are connected respectively to the first and third phases of the mains, and the anodes of the fourth 15 and

5 fifth 16 diodes are connected respectively to the first phase of the stator winding of the first electric motor 1 and to the third phase of the stator winding of the second electric motor 2, the cathodes of the sixteen 17 and seventh 18 diodes are connected respectively to the first phase of the stator winding of the second electric motor 2 and to the third phase of the stator winding of the first an electric motor, an anod5 and a 17th and seventh 18th diodes are connected respectively. through the fifth 29th and 30th the closing contacts of the brake contactor respectively to the connection points of the valve cathodes 3 and second 4 three-phase bridge rectifiers.

The device works as follows.

When starting, the stator windings of motors 1 and 2 are connected to the mains, close the contacts of the contactors 31 and 32 of the direction, and their acceleration begins. The resistance of the three-phase saturation reactors 6 and 7, depending on the frequency of the current flowing through them, decreases as the motors 1 and 2 accelerate, which allows the start of the motors 1 and 2 without additional switching equipment. The speeds of the electric motors 1 and 2 are synchronized by comparing the voltages of the bridge rectifiers 3 and 4 on the first resistor 5. In case of inequalities of the speeds of the electric motors 1 and 2, the equivalent resistance in the rotor circuit of the motor having a higher speed increases and the motor having a lower 25 and seventh diodes, second, third.

speed decreases. This leads to self-leveling of the speeds of the electric motors 1 and 2. In case of inequality of the currents flowing through the circuits of the rotors of the electric motors 1 and 2, currents of different magnitudes flow through the three-section windings 9 of the control (biasing). The greater the amount of current flowing through the winding 9, the

less equivalent resistance to choke. Consequently, a greater equivalent resistance of the corresponding throttle is introduced into the rotor circuit of an engine with a higher current, and an immaterial 40 first and second diodes corresponding to a smaller current is introduced into the rotor circuit, a smaller equivalent resistance of the corresponding throttle, which allows the rotors to equalize engines.

During dynamic braking of the chronically controlled motor and to the first water, the contacts of the contactors to the stator winding phase of the second electric 31, 32 directions open and close the contact motor through the cells of the brake contactor 25 and 30. The discharge current of the previously charged capacitors opens the thyristors 19, 20 and around the second resistor and in series with the stators of the motors of the electric motors the connected fifth resistor, the control current flows from the network. The charging circuit, for example, the electric motor 1 is as follows: the third phase of the supply voltage, the thyristor 19, the resistor 55 respectively to the first and third light 21, the stator windings of the electric motor of the supply mains, the anodes of the fourth body 1, the diode 15, the first phase supply voltage. After excitement

Through the first and second closing contacts of the brake contactor, respectively, they are connected to the third phase of the stator winding — the first asynoned fourth resistor, the control electrode of the first thyristor and

the electrode of the second thyristor and the third resistor, the cathodes of the fourth and fifth diodes are intended for connection

and fifth diodes are connected respectively to the first phase of the stator winding

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electric motors flow current through their rotor circuits and the stator windings of the motors, along with the feed current, are fed by the rectified rotor current, with the stator windings of the engine 1 being fed by the rectified current of the rotor of the engine 2, and the stator windings of the engine 2 - rectified by the rotor current of the engine 1. This ensures that the motor speeds are self-leveling during the braking process. The presence of charging current for the stators of the engines during the entire braking process eliminates the possibility of self-excitation of motors 5, which increases the reliability of the device.

Claims (1)

Invention Formula Twin motor drive on auth. St. No. 1176436, about tl and h and Yu and shch with the fact that, for the purpose of increase in reliability, two thyristors are entered into it, the fourth, fifth, sixth the fourth and fifth resistors, two contactors with three closing power contacts each, the brake coitator is equipped with the fifth and sixth closing contacts, three closing contacts of each of the contactors are included respectively in the stator windings of each of the electric motors, the anodes of each of the thyristors are intended for connecting respectively to the first, third phases of the supply circuit, and the cathodes of these thyristors are connected to the first terminals of the second and third resistors, respectively, the cathodes Through the first and second closing contacts of the brake contactor, they are connected respectively to the third phase of the stator winding of the first asynchronous electric motor and to the first phase of the stator winding of the second electric motor through a series of co-resistor and series-connected fifth resistor, which controls respectively the first and the third the mains power supply, and the anodes of the fourth a single fourth resistor, the control electrode of the first thyristor and of the chronical electric motor and to the first phase of the stator winding of the second electric motor through successively co-resistor and successively connected fifth resistor, which controls respectively the first and the third power supply network, and the anodes of the fourth the electrode of the second thyristor and the third resistor, the cathodes of the fourth and fifth diodes are intended for connection of the chronical electric motor and to the first phase of the stator winding of the second electric motor through successively co-resistor and successively connected fifth resistor, which controls respectively the first and the third power supply network, and the anodes of the fourth and the fifth diodes are connected respectively to the first phase of the stator winding5I3I09866 ki of the first electric motor and to the thra electric motor, anodes of the sixth and The second phase of the stator winding of the second-seventh diode is connected to the corresponding electric motor, the cathodes of the sixth diode through the fifth and sixth end of the seventh diode are connected to the corresponding contacts of the brake contactor to the first phase of the stator winding, respectively, to the junction points ki of the second electric motor and to the three cathodes of the first and second gates phase of the stator winding of the first three-phase bridge rectifiers.