SU1676035A1 - Method of regulation of electric power in loads connected in parallel - Google Patents

Abstract

The invention relates to electrical engineering, in particular to converter equipment. The purpose of the invention is to increase reliability and power factor and reduce noise. In accordance with the method, power control is performed by changing the number of loads simultaneously connected to the power source, as well as by changing the number of voltage periods in a time equal to n periods, where n is the number of loads for which each load is connected to the network. Each of the loads is divided into two sections, each of which is connected to the voltage source in the corresponding half-period, thereby achieving the goal. 4 ill., 1 tab. V ё

Description

The invention relates to electrical engineering, in particular to semiconductor converter technology.

The purpose of the invention is to increase reliability, increase power factor and reduce noise.

FIG. Figure 1 shows the power part of the circuit for implementing the proposed method with two pairs of electrical loads and power from a single-phase network; in fig. 2 is a control circuit of the power unit: in FIG. 3 and 4 are timing diagrams explaining the proposed method.

The method can be implemented with a thyristor power controller consisting of a load in the form of resistors 1-4. Resistors 1 and 3 are each connected to the cathode of thyristors 5 and 6, and resistors 2 and 4 are each connected to the anode of thyristors 7 and 8. Anodes of thyristors 5 and 6 and cathodes of thyristors 7 and 8

connected and form one input pin, and the conclusions of all resistors are connected to the second input pin. The basic electrical control circuit of thyristors 5-8 (Fig. 2) contains a synchronization unit 9, a pulse counter 10, shapers 11 and 12 pulses, a power supply unit 13, switches 14-16, a switch 17, included in the pulse former 11, and a switch 18. Part of the driver 12 pulses.

Pulse driver 12 contains a multivibrator on transistors 19 and 20, capacitors 21 and 22 and resistors 23-28, a differentiating chain from capacitor 29 and resistor 30, and an output stage from transistor 31, diodes 32 and 33 and a pulse transformer 34, Pulse former 11 contains a multivibrator on transistors 35 and 36,

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capacitors 37 and 38 and resistors 39-44, a differentiating chain of capacitor 45 and a resistor 46 and an output stage of transistor 47, diodes 48 and 49, and a pulse transformer 50.

The method is implemented as follows.

The mains voltage through the switch 14 is supplied to the power supply unit 13, in which the necessary voltages are formed to power the individual elements of the control system. The sinusoidal voltage (FIG. 3) is supplied to the synchronization unit 9, which generates square-shaped pulses synchronized with the network voltage i (Fig. 3). The rectangular pulses are fed to the input of the pulse counter 10, which divides the frequency of the incoming pulses into two.

From the first output of the pulse counter, the pulses Uiri (Fig. 3) through the switch 16 arrive at the input of the driver 11 pulses, and the pulses from the second output of the counter 10 pulses Urr2 (Fig. 3) through the switches 15 and 16 arrive at the input of the generator of 12 pulses pulses to control thyristors 5-8.

In the absence of input pulses, the switches 16-18 are open, and the drivers 11 and 12 of the pulses are in standby mode, the signal to the thyristors 5-8 is not received.

The implementation of the adjustment method is explained in the table, in which the correspondence between the state of the switches 14-18 and the diagrams 51-55 (FIG. 4) characterizing the power allocation on the loads is shown.

To provide power control P, which corresponds to voltage diagram 51, switches 14 and 16 are in a closed state, and switches 15, 17, and 18 are in an open state. At the same time, the signal from the pulse counter 1Q is fed to the input of the pulse generator 11, which generates pulses with a steep front and a short duration Uyi (FIG. 3) to control the thyristors 5 and 6.

To provide a 2P power controller, which corresponds to voltage diagram 52, switches 14-16 are closed, and switches 17 and 18 are open. The signal from the pulse counter 10 is fed to the input of the formers 11 and 12 pulses, where Uyi and Uy2 pulses (Fig. 3) are formed to control the thyristors 5-8, which connect the resistors 1-4 to the load alternately to the power supply:

The power in the 2P load can also be obtained in accordance with diagram 53 if the switches 14, 15 and 17 are closed, and the switches 16 and 18 are open. In this case, pulse driver 12 is in standby mode, and driver

11 pulses continuously apply a control voltage to thyristors 5 and 6, which connect the resistors 1 and 2 of the load to the power supply voltage every half period.

In order to provide a power regulator ZR, which corresponds to diagram 54, the switches 14, 16 and 18 are closed, and the switches 15 and 17 are open. Shaper

12 pulses continuously apply a control voltage to thyristors 7 and 8, which connect the resistors 3 and 4 of the load to the power supply voltage every half period.

From the pulse counter 10, a signal is fed to the input of the pulse driver 11, where pulses are formed to control thyristors 5 and 6, which connect resistors G and 2 to the power source through a voltage period.

To provide a 4P mode power controller, which corresponds to diagram 55, switches 14, 15, 17 and 18

0 closed, and the switch 16 is open. Shapers 11 and 12 pulses continuously supply control voltage to thyristors 5-8, which connect load resistors 1-4 to each half-period of the supply voltage,

Claims (1)

Claims The method of electric power control on n parallel loads, where n 2, 3,4 ..., in which the loads are connected in series every at least one alternating voltage period for a time equal to n periods of the input voltage, while the change in the total power on the loads is made by changing the number of simultaneously switched loads, characterized in that, in order to increase reliability, increase the power factor and reduce the noise level, additional changing the total power by connecting one of the n loads to the input voltage and changing the number of periods of the input voltage over a time equal to n 5 periods for which one of the loads is connected to the input voltage, in addition, each load is divided into two sections, each of which is connected to the input voltage in the corresponding half-period of the input voltage. NOTE. (+) Corresponds to the Enabled position, (-) - to the Off position. P 1