SU731509A1 - Device for single-phase automatic reconnection of power transmission line - Google Patents

Description

the secondary windings of a line voltage transformer (bus) connected to an open triangle. It is also possible the combined inclusion of a relay body is zero, in which the relay organ responds to the maximum of these two quantities — a current or a zero line carrying line.

The disadvantage of these devices is the lack of redundancy reservations for electoral authorities and a very difficult phase to phase interface. - biphasic r. 3, to the ground.

In this case, the blocking practically always works and forms a command that prohibits disabling the three phases of the nominative bodies.

The purpose of the invention is to increase the reliability of the electron transmission and the possibility of blocking the three-phase OTJCHO line at close two-phase-to-second lines. to the ground.

This is achieved by the fact that, in a device for OAPV, a power line equipped with a high-speed relay protection blocking the value of a three-phase line disconnection at one phase k. 3. consisting of zero sequence relay and a braking voltage generator intended for connection to current measuring transformers and the voltage Lynn, the Delay and Return element, and the Inhibit element, intended to switch on the three-phase line disconnection from the fast-acting relay protection on the day, iric, the output of the brake voltage tester is connected to the brake input of the relay body, the output of which is connected to the input of the Delay and return element, blocking of the three-phase circuit of the supply line with an additional relay element and the second element Zairet, and the input of the additional relay element is connected to the output of the brake voltage former, and the output - to the prohibitory input of the second element Prohibition, connected between the output of the Delay element for returning and terminating 1, which is the input input of the first element Zaire t.

In this case, the brake voltage driver is equipped with three phase brake voltage formers, an adder, a max selector and an inverter, and the inputs of the phase brake voltage formers are designed to be connected to the line current transformers, and the outputs to the three inputs of the adder and the max selector respectively the output of the max selector and the jumper connected to the fourth input of the adder, the output of which is connected to the output of the braking voltage driver.

At the same time, the voltage t / x at the output of the brake voltage former is about the sum of the phase brake currents minus the largest of them

, J (Phew ;; - max (f,;), (1)

i i

where O, 1, t, - is the phase braking voltage, depending on the phase current / f, phase 1; for example, rnc current

start braking / f.t. can be done so that

bft; - L I / ft1 - / f nt I- (2)

FIG. 1 shows the structure diagram.

proposed device; FIG. 2 is a structure diagram of a braking force generator.

To the substation switchgear 1, the switch 2 is connected to the electric line 3, to equip measuring voltage transformers 4 and 5, and is equipped with high-speed protection 6 and an OANV device 7. The zero-sequence relay element 8 and the braking voltageformer 9 are connected to the corresponding measuring circuit. These 4 and current 5 liy. The output relay relay 8 is connected with the input element 10 Delay and return. The first element and the interdiction is connected between the output of the high-speed protection 6 and the circuit 12 of the three-phase disconnection. A braking voltage is connected to the output of the braking unit 9 by reacting a braking voltage to the additional relay relay element 13, the output of which is connected to the inhibitory input of the second element 14 Prohibiting the blocking of the three-phase disconnection of lines and

included between the output of the element 10 and the prohibitory input of the elemental element 11 Prohibition.

The brake driver and pressure generator 9 can be performed, for example, according to the structure scheme of FIG. 2, where it is the remainder of the following obosiachii:

15, 16 and 17 — formers of phase braking voltages from currents of phases A, B and C, respectively,

18 - adder

19- maximum signal selector - max selector,

20- analog type inverter. The inputs of the formers 15, 16 and 17 of the phase brake voltages are connected to the phase measuring transformers 5, and their outputs are connected to the corresponding inputs of the adder 18 and the maximum selector 19. The output of the maximum selector 19 is through

the inverter 20 is connected to the fourth input of the adder 18, the output of which is the output of the entire braking voltage driver, and connected to the inputs of the relay body 8 n of the additional relay

item 13.

The operability of the proposed device is determined by the fact that the braking voltage (at the output of block 9) is single-phase K. 3. CR and full phase and single phase phases, sonojustry, does not have much to do with the same voltage at close mlsdufzykh to. Particular prn biphasic K. h. Therefore, if you select the voltage triggered by the tandem relay element 13 built from the first modes. it may be sensitive to second steps and prohibit the blocking of the three-phase disconnected.

The device works as follows.

At close single phase to. H. The current (voltages at the beginning of the line) contain a large amount of 10H1, its zero-sequence (): and the braking voltage in accordance with equations 1 n 2 is small (/ A / n; / V / s 0; f / T 0). The relay body 8 is triggered, and the relay element 13 does not work. The signal from the output of the relay body 8 through the element 10 Delay for return, the second element 14 The prohibition passes to the prohibiting input of the first element AND The prohibition that breaks the circuit 12 disconnected from the three phases of the line from high-speed protection 6 starts the control loop.

When deleted, s. On lnnnn with the participation of the earth current is small, the braking voltage is small, the relay body 8 should operate, and the relay element 13 does not work, i.e., two-phase to. both damaged phases are immediately selected on the ground or on the ground organs, either by cascade disabling the damage to the nrn single phase K. h. - cyclical OAPV.

With close two-phase c. S. on the ground was un1, not null but

are large (/ B / c 4V; 31o "/ V therefore, despite the large braking stress (/ t / C / fk), relay body 8 is activated and through element 10 it sends a signal to the input of the second element 14 Prohibited. However, to the prohibitory input of the first element 11 the prohibition of this valve does not pass, because under the action of a large braking voltage, the relay element 13 triggers the terminal to the prohibiting input of the second element 14 Prohibition If this causes the speed of operation 1 and protection of the 6 line, then three lines of the line are quickly disconnected.

The magnitudes of the brake voltages can be determined, for example, using equations 1 and 2, the values of which are followed by those that have been used above the previous work of the device.

Thus, it cannot be said that this device allows to exclude the blocking of the three-phase chain and the disconnection of near-phase interfacial circuits. The use of the donor relay element 13 in conjunction with the second element 14 Zanret makes it possible to significantly simplify the required braking response of the relay body 8 to notify it in non-transitory processes.

Introduction of an additional relay element 13, which is triggered at two-phase k. 3. nrn current / add. cf., it is necessary to limit the dependence of the current of operation of the same type. h. up to L p- / dop. Wed, where KP is the reliability coefficient (/ Cn «1.5). In the case of a false response, the relay body 8 prn interphase r. 3. prn nalnnn apernopic component of the current, the distorted shape of the reddish n t. The factors that most manifest themselves at close to zero. In the case of a full-length relay element 13, it is possible to quickly align the position and disconnect without slowing down all three phases of the line, even in the event of a failure of electoral authorities.

When using this device, it is advisable in all cases of a single-phase automatic switch-on transmission,

This does not mean a matter of suf fi ciency to which a zero sequence of the current line is applied, a combination of the one and the other reacts to the relay organ of the blocking device of the three-phase disconnected electoral authorities.

The techno-economical effect of the inventive invention is achieved due to the reliability of the electronic transmission to increase the speed of the three-phase disconnected at close phase-to-phase short circuits, including with the participation of the earth.

45

Claims (2)

1. A device for single-phase automatic reclosing of an electronic transmission line, equipped with a fast-acting relay protection device, a device for blocking a three-phase disconnection of a Linnn nrn single-phase short circuit, a neutral zero-relay relay body and a braking torch carrier circuit, intended for use by a zero-phase relay body line voltage, Delay for return and Zanret element intended to be included in the circuit The technology is disconnected from high-speed speech protection, in particular, the output of the brake inhibitor is connected to the brake input of the relay body, the output of which is connected to the input of the element Return delay, characterized in that, in order to improve the reliability of the power transmission by blocking the reset unit. in case of close two-phase short circuits on the ground, blocking of the three-phase disconnection line of the siabzhen by an additional relay element and the second element Barring that, the additional input relay to the output element nodklyuchen Jairus shaper zheii braking, and an output - to the input of the second element prohibiting prohibition between the output elemeita delay and return the first element prohibiting entrance prohibition. 2. Device for and. 1, characterized in that the brake voltage driver is equipped with three phase brake voltage formers, an adder, a max selector and an inverter, and the inputs of the phase brake voltage formers are predetermined to be connected to line current transformers, and the outputs for the three inlets of the summer and maximal voltage sensors for the line current transformers, and the outputs for the three inlets of the adder and max. accordingly, the output of the max-selector through the inverter and the switches to the fourth input of the adder, the output of which is connected to the output of the driver and brake voltage. Sources of information taken into account in the examination 1. The device of automatic and repeated switching on of APV-503. Technical description and operating instructions. Obk 469517 Cheboksary Electric Equipment Plant. Ed. 01 (ChEAZ), p. 31. 2. High-speed device for automatic re-activation of VL 750 kV type APV-750. Technical materials on prototypes. Parts I and II. State No. registration 73013627 VNIIE, M., 1974.