SU1361671A1 - Device for checking alternation of phases of three-phase a.c.voltage source with zero lead - Google Patents

Abstract

The invention relates to electrical engineering and is intended for use in a power supply system where it is necessary to control the alternation of the phases of a three-phase alternating voltage source with a zero output. The purpose of the invention is to simplify the device. The device contains tr1 diodes 1-3, resistor 4, phase-sensitive blocks 5 and 6, phase terminals 7-9 of the source, zero output of the power source 10, gas discharge thyratron 11, resistors 12 and 13, second gas discharge thyratron 14, resistors 15 and 16 , thyristor 17, incandescent lamp 18, thyristor 19, LED 20, thyristor 21, winding of electromagnetic relay 22, capacitor 23. When reverse phase alternations in the order of 8, 9, 7, in the first third period a current pulse passes through diode 2, resistors 16 and 4. At the same time, due to the voltage drop across the resistor 16 through a resistor 15 and the control electrode with a cathode tira- throne 14 passes current podgotavlivayu- ® conductive to its inclusion. When the voltage of phase 9 exceeds the voltage of phase output 8, the thyratron is ignited. 4 il. O5

Description

The invention relates to electrical engineering and is intended for use in power supply systems where a certain alternation is required outside the phases of a three-phase alternating voltage source.

The purpose of the invention is to simplify the device.

FIG. 1 shows a diagram of the pre-io passage of a current pulse of a luminous device with phase-sensitivity. In the third part of the period, when the voltage of phase 8 exceeds the voltage drop across resistor 4, it goes through 15

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body blocks made on gas discharge thyratrons; in fig. 2 - 4 - diagrams of phase-sensitive blocks, made respectively of the thyristor and incandescent lamp, thyristor and LED, thyristor and electromagnetic relay.

The device (Fig. 1) contains three diodes 1-3, a resistor 4 and two phase-sensitive blocks 5 and 6, the control inputs of which are connected to the cathodes of the first 1 and second 2 diodes, the first inputs are connected to the cathode of the third diode 3, the second inputs - to the first terminal of the resistor 4, the anodes of the diodes 1,2 and 3 are connected to the phase terminals 7, 8 and 9 of the source, the second terminal of the resistor 4 is connected to the zero terminal 10 of the source. The phase-sensitive unit 5 is designed as a bi-stable display element, of a gas discharge thyratron 11, whose control electrode, when connected to the control input through the resistor 12, the anode to the first input, the cathode to the second input and through the resistor 13 to the control input of the phase-sensitive unit 5.

The phase-sensitive unit 6 is made similarly in the form of a bistable display element consisting of a gas discharge thyratron 14 and resistors 15 and 16.

The bistable display element i (Fig. 2) is made of a series-connected thyristor 17 and an incandescent lamp 18, or a series-connected thyristor 19 and an LED 20 (FIG. 3) or of a series-connected thyristor 21 and a winding of an electromagnetic relay 22 biased by a capacitor 23 (Fig. 4).

The device works as follows.

With direct phase rotation in the order of 7, 9, and 8, in the first third of the period, a current pulse passes through diode 1 and resistors 13 and 4. In this case

pulse current through the circuit diode 2 - resistor 16 - resistor 4. At the same time, the thyratron 11 and diode 3 are locked.

In the reverse phase sequence in the order of 8.9.7, due to similar processes, only the gas discharge thyratron 14 is ignited.

When performing phase-sensitive blocks 5 and 6 in the form of bistable display elements on the thyristor 17 and the glow lamp 18 (Fig. 2) or on the 25 thyristor 19 and the LED (Fig. 3), the device operates in a similar way. Light-emitting elements may be part of the optocoupler of the executive body. When performing phase-sensitive blocks on the thyristor 21 and the electromagnetic relay 22 (Fig. 4), the executive body is the contact group of the relay.

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The embodiment of phase-sensitive units on gas discharge thyratrons is characterized by low values of consumed currents and power, therefore, it is convenient at high source voltages, and variants using LEDs and incandescent lamps at low voltages.

When the frequency of the monitored voltage varies, only the frequency of the current pulses through the light emitting elements changes.

When using bistable display elements designed for controlling and supplying negative polarity voltage, for example, two-transistor thyristor analogs, the polarity of switching on diodes 1, 2 and 3 and the diode 20 is reversed and cathodes are connected to the phase terminals 7, 8 and 9 of the source diodes 1, 2, and 3.

due to the voltage drop across the resistor 13 through the resistor 12 and the control electrode – cathode circuit of the thyratron 11 passes a current preparing it for switching on. Therefore, after the voltage of phase 9 exceeds the voltage of phase 7, the anode-cathode of the thyratron 11 is ignited and due to

pulse current through the circuit diode 2 - resistor 16 - resistor 4. At the same time, the thyratron 11 and diode 3 are locked.

In the reverse phase sequence in the order of 8.9.7, due to similar processes, only the gas discharge thyratron 14 is ignited.

When performing phase-sensitive blocks 5 and 6 in the form of bistable display elements on the thyristor 17 and the incandescent lamp 18 (Fig. 2) or on the thyristor 19 and the LED (Fig. 3), the device works in a similar way. Light-emitting elements may be part of the optocoupler of the executive body. When performing phase-sensitive blocks on the thyristor 21 and the electromagnetic relay 22 (Fig. 4), the executive body is the contact group of the relay.

The embodiment of phase-sensitive units on gas discharge thyratrons is characterized by low values of consumed currents and power, therefore, it is convenient at high source voltages, and variants using LEDs and incandescent lamps at low voltages.

When the frequency of the monitored voltage varies, only the frequency of the current pulses through the light emitting elements changes. While maintaining the duty cycle of the pulses, the intensity of the luminescence does not change.

When using bistable display elements designed for controlling and supplying negative polarity voltage, for example, two-transistor thyristor analogs, the polarity of switching on diodes 1, 2 and 3 and the diode 20 is reversed and cathodes are connected to the phase terminals 7, 8 and 9 of the source diodes 1, 2, and 3.

3136167

Claims (1)

Invention Formula A device for controlling the alternation of the phases of a three-phase alternating voltage source with zero output, containing three diodes, a resistor and two phase-sensitive units, with their control inputs connected to the cathodes of the first and second diodes, 10 first inputs connected to the cathode of the third diode, the second inputs to the first output. resistor, anodes pred1 assigned to connect to the phase outputs of the source, the second output of the resistor is designed to connect to the zero output of the source, characterized in that, in order to simplify the device, each phase-sensitive unit is designed as a bistable display element, the control output of which is connected to the control input , the anode - to the first input, the cathode. - to the second input of the phase-sensitive unit. Figt Compiled by L. Korneev. I. Gorn Editor. Tekhred L. Serdyukova. Proofreader L. Patay. Order 6300/54 Edition 618 Subscription VNIJUTI USSR State Committee by . Inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Project St., ( Fig.d FIG.