SU435149A1 - DEVICE FOR THE DISTRIBUTION OF THE CURRENTS BY PARALLEL BRIDGE ELECTRIC MOTORS - Google Patents

Description

one

This invention relates to static converters of direct current and intended use;} for equalizing current between real-time electrical machines, connected in several: parallel branches.

Apparatus are known for supplying the drive windings of traction motors in traction modes and electric braking from a static converter transformer through adjustable rectifiers, which are controlled from a current sensor through phase shifting blocks and control current pulse shapers. In this case, the controlled rectifier transmits the entire excitation power, which causes a sharp increase in the number of thyristors and complication of the control system, and the power supply to each rectifier through low-voltage windings of the transistor, its power transformer leads to a continuous iiepaBHOMCpnocTH load distribution across the motors due to the unequal load on the motor. low voltage windings in the presence of an automatic control by excitation exciters, the mutual influence of transformer windings on the distribution of loads and unequal inductance dissipation of the low-voltage windings of the power transformer with respect to the primary winding.

The purpose of the invention is to reduce the installed power of electrical equipment at

using a common power source to excite traction motors, increase speed and simplify the circuit.

This is achieved by the fact that the excitation windings of each branch of the traction electric motors are connected iK to the exciter in series through an additional rectifier, the input of which through a step-down transformer and a symmetric controlled electric valve is connected either to the secondary winding of the inverter static converter or to the output of the additional inverter when powered windings of excitation from the mascal exciter. And in order to increase the sensitivity and speed of the device is equipped with a switch "pulses", connected to the output of the current pulse shaper control symmetrical controlled electrical ventilators, each of which is connected in parallel to the primary winding of its additional transformer and these primary windings are connected in series. With a simplification, the step-down transformer of the device is equipped with additional secondary windings connected to rectifiers via the secondary windings of additional transformers, while the control electrodes of symmetric controlled electric valves are connected to the output of phase-shifting devices,

connected to the driver of current pulses of the thyristor control of the static inverter inverter and the current sensor outputs of the above DC machines.

FIG. Figure 1 shows the electrical circuit of the device for the distribution of current and load between parallel winds of traction electric motors, three power supply to excitation from the common, its static converter of autonomous rectifiers; on f-ig. 2 shows a diagram of a device when threading excitation windings of traction motor motors from its common static converter at a series connection of the primary Obmok nizhayush, their transformer / ditch and Jummer with their symmetrical controls; in fig. Figure 3 is a schematic diagram of the rectifying device of the current distribution system between the parallel branches of the motors with a serial connection of the windings of the transformers.

The device for current distribution between parallel branches of the traction electric motors contains symmetric electrically controlled gates 1, 2, low, transformers 3, 4, two single-phase rectifiers, filled with diodes 5-S and 9-12, for mars 13 14 control pulses with phase-shifting devices and current sensors 15. 16. The excitation windings 17, 18 and 19, 20 are connected to the output of the static converter in series through rectifiers and diodes 5-8 and 9-12. The rectifier is fed from inverter 21 through symmetrical balanced electric fans and 1, 2: step-down transformers 3 and 4 and an inverter transformer 22. Field windings 17, 18 and 19, 20 are fed from inverter 21 via transformer 22, converter rectifiers All types of diodes 23-26 and 27-30.

The control current pulses for unlocking the thyristors of the inverter 21 and the phase shifting blocks of the formers of the current immersions 13, 14 are formed by the control unit 31.

The current sensors 15, 16 are each connected in series to a circuit of Korean traction motors 32, 33 34, 35.

The static inverter 21 inverter: the explorer provides an inversion of the constant voltage at its input to the variable rectangular base with a short pause.

In the initial state, when the load currents of the th 32 electric motors 32, 33 and 34, 35 equals 7 | Ы each other, the control current pulses supplied by the low voltage electrodes of the symmetric controlled electric valves 1, 2 from the current formers and 13 of them. , 14, have the same phase shift, 90 al. hail. In this case, the excitation currents also have the same value.

The increase in load current on one of the branches of traction electric motors, for example, in

in motor circuits 32, 33 when operating in the pull mode, it leads to an increase in the voltage of the output of the current sensor / 5 and causes a decrease in the phase shift between voltage 5 at the output of the inverter 21 and the shape of the m current pulse 13 When reducing the phase shift nmpulsoB current from the output of the imaging unit 13 increases the voltage at the output of the rectifier, made on the diodes

1Q 5-8, WHAT, in turn, causes an increase in the excitation current of the electric motors 32, 33 and the voltage on their brushes. As a result, the load current of the electric motors 32, 33 is reduced.

- When the actuators 32, 33 are operating in regenerative braking mode, the direction of the current in the sensor circuit 15, 16 is reversed and the polarity of the voltage on their output is reversed. With this: M an increase in the load of the electric motors 32, 33 leads to an increase in the negative voltage at the output of the sensor 15 and causes an increase in the phase shift of the current pulse of the I control to the control electrode of the measuring meter of the controlled valve. When ethol decreases the voltage at the output of the rectifier 5-8 and the excitation current of the electric motors 32, 33, H1H) leads to a decrease in the voltage of the motors x and a decrease in the load current on them.

0 For the increased sensitivity of the described device for distributing the load current between parallel branches of traction motors, the primary windings of transformers 3, 4 are connected 1 sequentially and are bridged each by symmetrical control of the electric valves / and 2, and the PmMile switch of the control current is additionally inserted, providing supply current control pulses

0 either to the control electrode valve /,

or control electrode valve 2 in

depending on the mode of operation of the engines and

load current distribution (Fig. 2).

With this construction of the system in the original

5, when the load currents of the motors of both branches are equal to each other, the control current pulses, generated by the shape of: the worlds 13, are shifted relative to the impulse voltage of the inverted voltage and 180 el. hail.

Q and is supplied to the monept, coinciding with the pause of the inverted voltage. In this case, the symmetric controlled electric gates /, 2 remain in the off state, and the voltage at the output of the rectifiers 5-5 and 9-12 are equal to each other. This depletes

5 equality of drive currents of electric motors 32, 33 and 34, 35.

When increasing the load current on one of the branches of electric motors, for example, 32, 33, when operating in the traction mode,

0 nanr 1x the output of current sensors 15, 16 hundred; novigs positive m. This reduces the phase shift between the inverted voltage and the current pulses at the output pho,

world leader 13. The phase shift and control pulses are proportional to the difference in load current between the motors of the traction motors. With a positive polarity of the Parallel voltage pa of the output of the jigate current sensors. The switch provides the impulses of control current B to the control circuit of the electric electrified electrode 1. Turning on the leps / causes an increase in the voltage of the rectifier bridge 5-8 and a decrease in voltage at the output of the bridge 9-12, which, in turn, leads to an increase in the current excited by the motor 32, 33 and the elevation of the excitation current P1 of the electric motors 34, 35. At the same time, the load current of the electric motors 32, 33 decreases, and the load current narrow motors 34, 35 is increased.

An increase in the load of the traction electric motors 32, 33 when they are operated in regenerative braking, or the decrease in the load current of the indicated motors when they are operated in the thrust mode with respect to the electric motors 34, 35 causes a change in the polarity of the resulting ia fi on current sensors 15 , 16 and the transfer of current impulses is corrected from the control electrode of the valve / wiravap, and the electrode of the propyl 2. The inclusion of a symmetrical controlled electric Veptll 2 causes the voltage to decrease at the output of the bridge 5-8 and increase NIJ PDS voltage at the output of the bridge 9-12, which causes reduced-s drive current motors 32, 33 and an increase in current drive motors 34, 35 and corresponding nereraspredele s load current between the parallel legs of the motors 32, 33 and 34, 35.

Thus, the described ycTpoijCTBO ensures the equality of the load current between the parallel branches of the engines, both in the current mode and in the regenerative braking mode. Switching on the SI |: -.: .Metlch1zd1kh controlled gates according to the scheme in FIG. 2 causes an increase in the excitation current of one branch and a decrease in the excitation current of the other branch of the motors when the load currents are unequal; ;; - ;; (in parallel and in the branches of the motors. At the same time, the excitation current is controlled only by a symmetric controlled valve at smaller angles of conductiveness, which leads to an increase in the sensitivity of the proposed system and to a decrease in the load current by symmetric controlled Veptlis.

P -;) t. 1 up to the interplay of the connection of the windings of the ponies of transformers (Fig. 3} simplifies the rectifier circuit, for example, for this, the secondary windings of the rectifier sequentially with the secondary windings of the coformer aspraumer The number of drivers is reduced from four to two.

The described device can be used for the equal distribution of the load current across parallel branches of the direct current electric locomotives with the supply of the excitation windings from the power converter. In this case, the inverter 21 is connected to the output of the machine converter and from the circuit; ia FIG. 2, common transformer 22 and rectifier 23-26 and 27-30 are excluded.

The described device can be used to load load current between parallel branches of an electric locomotive engine, rail track and a number of other electric drive systems with several engines, as well as to evenly distribute the load current of direct current generators in parallel operation.

Subject and reference about i

Claims (3)

1.Device for distribution of current 1 and between parallel branches of a traction electric motor of a low current, containing 1, its transformer and rectifiers with windings of excitation-type electric motors connected to them, symmetrical controlled electrical current sensors, phase-shifting and current pulse formers the control unit, which distinguishes telg, that, with. and the installation of the output power of electrical equipment when using a source, is supplied to:; olmitel: s.mprastorformator, connect to the terminal via the meter controlled electrically parallel to the transformer and complementary} I mn vnr mittel mn, BKlyuksn; N) l: on the n side (current in series with excitation currents 1, p. I peukg, occupied by rectifiers, and on the side of the southeast current, each connected to to your dopol 1te. trapsformator. 2. The device according to claim 1, characterized in that, with increasing sensitivity and speed, it is equipped with a switch of pulses, on the chip: | at the output of the impeller of the control current pulse with MN eTrpchimpmp controlled electric Veppl mp, from which the first 1 h-mo 1 winding of its additional trapspor 1 is turned on, these nervous windings are connected in succession. 3. The device according to paragraphs. 1, 2 characterized by the fact that, for the purpose of simplification, the trassformator is equipped with a DONOLNNTEL SM 1 VORNCH P, M OMOTKAM, podklennymi to vyp) m: Ptel m through the secondary windings before the x trapsformatoz.