SU1169129A1 - Multimotor electric drive - Google Patents

Abstract

MULTI-MOTOR ELECTRIC DRIVE, containing two electric motors, the main windings of which are shunted by the first and second diodes, respectively, and connected through the first and second thyristors to the power source, one output of which is connected to one output of the third thyristor, and also through a capacitor to one output of the throttles, the third and Fourth diodes, controlled by thyristor electrodes, are connected to the reference pulse generator by means of corresponding pulse delay units, characterized in that, in order to increase reliability, another The output of the throttle is connected to another output of the third thyristor, and through the third and fourth diodes - to the terminals of the main (L windings of electric motors.

Description

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: o The invention relates to electrical engineering, in particular to multi-motor drives used in various industries. The purpose of the invention is to increase reliability. FIG. 1 shows a diagram of a multi-motor drive; in fig. 2 - voltage diagrams. The multi-motor electric drive (Fig. T) contains two electric motors 1 and 2, the main windings of which are shunted by diodes 3 and 4, respectively, and connected through thyristors 5 and 6 to the power supply 7, one output of which is connected to one output of the thyristor 8, and also through a capacitor 9 - with one pin of the choke switches 10, diodes 11 and 12, the control electrodes of the thyristors 5, n 8 are connected to the generator 16 of the reference pulses through the corresponding blocks 13-15 of the pulse delays. . The second output of the choke switches 10 is connected to the second output of the thyristor 8 and through diodes 11 and 12 is connected to the terminals of the main windings of the electric motors 1 and 2. The multi-motor electrical device operates as follows. In the initial state, the capacitor is charged along the circuit: power source 7 - power capacitor 9 - choke 1, diodes 11 and 12, electric motors 1 and 2 - power supply 7 so that its left side is positive. As the trigger pulses arrive at thyristors 5 and 6, the latter are unlocked, and motors 1 and 2 are connected to power supply 7. After a certain period of time, set by the pulse delay unit 15, the trigger pulse from the output of this block is fed to the control electrode of the thyristor 8. The thyristor 8 is unlocked and the oscillating process of recharging begins: capacitor 9 along the circuit: capacitor 9 - thyristor 8 - choke 10 capacitor 9. The reverse half-wave current of recharging and thyristors 5, 6 and 8 are locked (the cathodes of the thyristors 5 and 6 receive a positive potential from the right capacitor plates through diodes 11 and 12). After the thyristor is locked, the capacitor 9 continues to recharge with the load currents 292 through diodes 11 and 12 and its left facing becomes positive again. After the completion of the recharge of the capacitor currents, the loads flow through the shunt diodes 3 and 4. Next, the thyristors 3 and 6 are again unlocked, the pulses and operation cycles are repeated. The linear diagrams of the voltage of the INR (Fig. 2) show the reference pulses U (jn, the pulses at the outputs of blocks 13-15 of the pulse delays (respectively 14.d, and.and Ujjp, and the voltage on the motors 1 and 2 (respectively)) The voltage values at the terminals of the electric motors can be adjusted independently of each other by changing the time tj..j3 and tj of the delay of the pulses fed to the thyristors 5 and 6 with blocks 13 and 14. To do this, the control voltages of these blocks must be changed accordingly. Simultaneous change in averages The voltages at the terminals of the electric motors can be made by changing the time tj., .. the delay of the pulses fed to the thyristor 8. Thus, the electric drive provides both independent (by changing u, 3 and U,) and coordinated (by, changes) the frequency control of the rotation of the electric motors 1 and 2. The pulse delay unit 15 can be excluded from the electric drive circuit. Then, an independent, and uncoordinated change of the frequencies of the rotation of the motors will be carried out by the appropriate (independent or asovannogo) varying actuating voltage. Thus, in the electric drive, in comparison with the known one, a simpler (with only one thyristor) device for switching the current of the power supply is used, which starts up for a very short period of time during each cycle, and therefore there is no need to count it on the maximum load current of the power supply. . The installed power of the device 3 is reduced. Since the current switching device contains only one thyristor, the control theme of the electric drive is simplified, which increases the reliability of the electric drive.

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Claims (1)

MULTI-MOTOR ELECTRIC DRIVE, containing two electric motors, the anchor windings of which are shunted by the first and second diodes, respectively, and connected through the first and second thyristors to a power source, one terminal of which is connected to one terminal of the third thyristor, and also through a capacitor to one terminal of the inductor , the third and fourth diodes, the control electrodes of the thyristors through the corresponding pulse delay units are connected to the reference pulse generator, which differs in that, in order to increase reliability, another output d inductor connected to the other terminal of the third thyristor, and through the third and fourth diodes - Leaded armature coils of electric motors.