RU3497U1 - DEVICE FOR POWER SUPPLY OF DC SUBSTATIONS - Google Patents

Abstract

A device for powering the DC circuits of substations containing a three-phase transformer, a rectifier and a control unit, characterized in that a voltage sensor and a double-layer capacitor are introduced into it, the control unit is made in the form of a comparison unit and an electronic amplifier with an output relay, the normally closed contact of which is connected between the positive terminal of the rectifier and the first terminal of the above capacitor, in parallel with which the load is connected, the second terminal of the capacitor is connected to the negative terminal in rectifier, the input of the voltage sensor is connected in parallel with the capacitor, and the output of the voltage sensor is connected to the input of the control unit, which is connected to the voltage regulator, the rectifier is uncontrollable, and the voltage across the capacitor is 0.85U≅ U≅ 1.1 U, where U is the reference voltage and the maximum output voltage of the rectifier is U = UU / U, where U, U are the maximum and minimum allowable voltages on the substation buses.

Description

DEYA PITCHM DEVICE OF DC SUBSTANCE SCHEDULE CIRCUIT

The utility model relates to electrical engineering and can be used to power relay protection equipment, automation, switching devices and signaling low-voltage substations 110-220 kV and distribution points 6-35 kV.

A device DEYA power supply circuits direct current substations containing a battery and charger

device for EQTQflJ.

The disadvantage of this device is that its maintenance requires duty personnel.

A large number of more complex power supply devices for DC circuits of substations 1 are known.

Their disadvantage is great complexity and low reliability.

The closest technical solution, which can be taken as a prototype, is a device for supplying direct current circuits of substations containing a cut-in transformer loaded on a thyristor rectifier by the first control unit.

The device also contains a second control unit with high speed and a protection unit against increasing the output voltage of the thyristor rectifier. The stabilization of the average value of the rectified voltage at the output of the thyristor rectifier is provided by the first control unit, by controlling the thyristors of the cathode group of the bridge, the second control unit by the rectifier is controlled by: thyristors of the 1 iodine group of the bridge, providing in normal power mode a nominal value of MH5G05FI / 46

- -1

input voltage, as well as the accelerated output of the rectifier to the nominal mode when it is connected to an alternating current network, the protection unit carries out protection against increasing the output voltage caused by one or more damage to the charger. The disadvantage of this technical solution is the difficulty of setting up the device and the need for qualified service: it.

The purpose of the proposed utility model is to increase the reliability of the device.

This goal is achieved by the fact that a voltage sensor and a double-layer capacitor are introduced into the device for powering the DC circuits of substations, which contains a three-phase transformer, a rectifier and a control unit, in parallel with which the load is connected, and the control unit is made in the input of the comparison unit and the electronic amplifier with output relay normally closed contact which is connected between the positive terminal of the rectifier and the first terminal of the above capacitor, the second terminal of which is connected to the negative nd terminal of the rectifier, a voltage sensor for, dklyuchen parallel capacitor, and the voltage sensor output is connected to the input of the control unit, which is connected to for, sensor .napryazheniya rectifier configured uncontrollable, the voltage across the capacitor is equal to

, /

where IJ is the reference voltage,

/ a maximum output voltage of the rectifier

  r // /: Wr

) f 3 j

//// - XSS X

1dB /// f / Lv maximum and minimum allowable

 /

bus voltage substation.

The invention is illustrated in the drawing.

The device for supplying direct current circuits of substations contains a three-phase transformer I, an uncontrolled rectifier 2, a control unit 3, which includes a comparison unit, an electronic amplifier with an output relay and N.C. contact 4 relays, voltage sensor 5, double-layer capacitor 6

N.z. Pin 4 of the control unit relay 3 is connected between one

from the terminals of the rectifier 2 and one of the cells of the double-layer capacitor 6, the other terminal 8 of the capacitor is connected to the other rectifier terminal, the voltage sensor 5 is connected to the double-layer capacitor clamps, & the voltage sensor is connected to the input of the control unit 3. The output of the control unit is the specified relay with N.C. contact ОХМ 4, which, when the voltage exceeds the double-layer capacitor of the set value, when the relay is switched on, it turns off. The control unit 3 is connected to a voltage setter 9. A load (not shown in the figure) is connected in parallel with the above capacitor. As the control unit 3, known

devices with an electronic amplifier and a comparison unit. with an output relay, oh, din normally closed contact of which is used in the proposed device circuit, an adjustable resistor or voltage sensors can be used as voltage sensors / Sj / Known elements / 4J / as a double-layer capacitor The device operates as follows.

When an AC voltage is applied to the transformer I, a voltage appears at the output of the rectifier 2, through N.C. pin 4

The relay of the control unit 3 controls the voltage at the same time to the load and to the dual layer capacitor 6, which accumulates electrical energy. When the voltage (/ on the double-layer capacitor reaches the set value, the control unit 3 turns on the relay included in the composition (not shown in the figure).

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while n.z. Pin 4 is disconnected, the load is powered by a two-layer capacitor 6, as a result, the voltage across the capacitor drops, the relay is disconnected, through N.C. pin 4 is the rectified voltage from the rectifier 2 to the capacitor 6, etc. In such a relay mode, the set value of the voltage across the capacitor is maintained, and hence the voltage across the load.

In case of malfunctions in the feeders, for example, short circuits, the mains voltage drops, the rectifier voltage drops, the load is powered for at least 10 seconds. is carried out from the capacitor, while the protection manages to disconnect the substation from

network.

For normal operation of the device, the voltage (/ on the capacitor should be equal to

0.85 L - i / c i 1.1

where 1 / is the reference voltage, / and the maximum output voltage of the rectifier

/

. -

, -

where / the maximum and minimum permissible voltage on the substation’s wheat.

The proposed device is simple in design, does not require qualified maintenance and is reliable enough,

LITERATURE

1. Power sources of REA (edited by G.S. Nayvolt. M .: Pa, i№ and communication, 1985, p. 301. Fig. 7-32.

2.A. C. USSR J 1654800, MKI5 5 / 1/4 6, Usstv o. For power supply of direct current circuits of substations. Auth. E.P. Korolev, S.M. Kutsovsky, E.M. Liberson, V.A. Danchenko, V.A. Cherednichenko. B.I. J 21, I99I, (prototype).

3. Lebedev E.D., Neymark V.E., Distrak M.Ya., Sledzhanovsky O.V., Control of DC valve electric drives.

Energy, 1970, 200 p. /. ,, -. /

 S /, L / 4 / / -7

4 .. F / W - / - - /

BW33 / JO

Claims (1)

A device for powering the DC circuits of substations containing a three-phase transformer, a rectifier and a control unit, characterized in that a voltage sensor and a double-layer capacitor are introduced into it, the control unit is made in the form of a comparison unit and an electronic amplifier with an output relay, the normally closed contact of which is connected between the positive terminal of the rectifier and the first terminal of the above capacitor, in parallel with which the load is connected, the second terminal of the capacitor is connected to the negative terminal in rectifiers, voltage sensor input is connected across the capacitor, and the voltage sensor output is connected to the input of the control unit, which is connected to the voltage setting unit, configured uncontrolled rectifier, the voltage across the capacitor is equal to
0.85U _s ≅ U _s ≅ 1.1 U _s ,
where U _s - sets the voltage
and the maximum output voltage of the rectifier is
U _{in m a x} = U ₃ U _{m a x} / U _{m i n} ,
where U _{m a x} , U _{m i n} - the maximum and minimum allowable voltage on the substation tires.