SU983872A1 - Remote protection quick-action stage - Google Patents

Description

(54) DEVICE OF HIGH-SPEED STAGE REMOTE PROTECTION

one

The invention relates to electrical engineering and can be used when carrying out remote protection of AC power lines.

The known distance protection device contains resistance relays, time relays, intermediate and index RT relays.

However, this device in a number of cases does not provide the required sensitivity in the event of a fault through a transitional resistance, since it does not have an extension of the response characteristics during a short loop.

The closest in technical desiccation effect to the proposed device is the remote protection comprising a resistance switch, a switching unit, the characteristic of the resistance relay operation, the current relay and power direction, the intermediate relay and the time relay 2j.

However, this protection does not provide an increase in sensitivity to short circuits through transient resistances under the condition of separation from the load modes, if the zones of the input resistances in the load modes and during short circuits have common areas

The aim of the invention is to increase the sensitivity to short-circuits through transient resistances while providing detachment from loading modes.

The goal is achieved by the fact that in a distance protection stage device, which contains three resistance relays, each of which is made in the form of series-connected formation unit of compared values, element of formation of mismatch impulses (coincidence) of the signs of instantaneous electrical quantities and the reacting organ, the characteristic switching unit

the operation of the resistance relay whose output is connected to the corresponding inputs of the formation blocks compares the quantity of quantities, and the logical element OR connected by inputs to the outputs of the resistance relay and the output of which is the output of the device, additionally introduced in series OR logic element and a reacting organ connected to the input of the switch of the characteristics of the Era, a bath of a resistance relay, and the output of each element of the formation of a mismatch (coincidence) pulse GOVERNMENTAL electrical quantities is also connected to the corresponding input of the newly introduced a logical OR gate.

FIG. 1 shows a functional diagram of the device; in fig. 2 shows the possible response characteristics of the resistance relay.

The device contains resistance relays 1,2 and 3, each of which is made in the form of successively connected units for generating compared values 4, an element for forming impediments of mismatch (coincidence) of signs of instantaneous electrical quantities 5 and a reacting authority 6, one logical element OR 7, the inputs of which 1 are connected to the outputs of resistance relays 1,2 and 3, the newly introduced logic element OR 8, the connections by inputs to the outputs of the elements of the formation 5, the series-connected reacting element 9 and the switching unit 10 Kteriotvk actuation of the relay resistance whose outputs are connected to the corresponding inputs of the formation units 4,

Resistors 1, 2 and 3 combined by the element OR 7, when triggered, affect the shutdown of the shutter, the element OR 8, the reacting body 9 and the switching unit 1O form an additional channel for measuring the duration of the signals of the instantaneous electrical quantities. When a reacting 9 is triggered, the switching unit 10 acts on the units 4 of the formation of the immediate: effective values, providing an expansion of the characteristic: the operation of the relay has a resistance of 1.2 and 3, and on return. body 9, ensuring their narrowing.

FIG. 2 shows the possible response characteristics of one of the resistance relays in the complex plane.

resistances: 11 - narrow character: tic (quadrangle Z, Zo, Z. 24 12 - broad characteristic (quadrilateral 7, ..., 22, an additional characteristic, formed by arcs resting on the sides of a wide or narrow quadrilateral depending on the state of the reacting body 9.

Depending on the modes of the monitored network, the protection functions as follows.

If in the unloading mode the measurements of all three turnips of resistance are

outside the extra wide characteristic, the reacting element 9 is in the activated state, with a wide printing characteristics of 12 relays of resistance of individual phases.

Protection is awaited with characteristics 12.

If, in the load mode, due to asymmetry of the load, at least one of the short-circuit measurements is inside the extra wide characteristic 1.2 vi, at least one is outside the characteristic 13, then the protection state will not change, since the reacting authority 9 is in the activated state, and rea

body 6 providing the characteristic

12 does not work.

If at least one of the measurements is out of the extra feature

13 and at least one - inside the visitor of characteristic 12, the protection is triggered, since at the output of the reacting authority 6, which provides a wide characteristic 12, a trigger signal appears. This mode corresponds to

asymmetrical damage disconnected by a wide-resistance relay 12.

If, at the switching of the load, point 7 for the relay, the resistance of all phases will be in the area of additional characteristics 13, then a & stroke is provided for narrow response characteristics 11, which are tuned from the maximum currents of the load mode; but

since the reacting authority 9. has a higher response speed than 6, the protection will not trigger. In this case, the additional characteristic rests on the sides of the quadrangle of the narrow characteristic.. It is possible that in this case, Z also turns out to be an enhanced additional characteristic. In order to eliminate the re-expansion of the TNCs' behavior of the resistance relay in this mode, it is possible to provide for monitoring the action of the additional channel for measuring VIEW from the interlocking device with such a mode that the x & expansion is possible only with its action.

If all three measurements of the resistance relay are covered by an additional characteristic 13 and at least one of the narrow characteristic ill, then the protection is triggered by detecting a short circuit in the zone | KI 11.

The operation of swing protection in principle does not differ from the functioning of known remote protection systems. In this case, a swing lock device is necessary, which ensures that protection is started for a given time when the asymmetry goes down and its output follows.

Increasing the sensitivity to short-circuit CMMs through transient resistances, while ensuring detachment from load modes, is ensured by the fact that the automatic expansion of the response characteristics is carried out with. the presence of asymmetric viam through transient resistance, and in the presence of a close symmetrical load, the characteristics are reduced.

The use of the proposed device allows to obtain a significant, technical, co-economic effect, which consists in increasing the sensitivity to short circuits through transient resistances while maintaining the detuning from the load modes; which increases the reliability of electric wiring.

Formula of invention

The device & 1 storied distant protection package containing turnips soprotiBlevv, each of which performed in a sequential sequence of the first block of the formation block: equal values, an element of the impulses of the weights, an instantiator, an organizer, an instr of an instant electrical pattern in the shape of an instantaneous organizer, an organizer, an organizer, an organizer, an instr resistivity: whose outputs are connected to the corresponding 1RM1 1M inputs of the blocks that form comparable quantities, and the logical element OR, connected by inputs to the output The am relay of the resistance and the output of which is the output of the device, characterized in that, in order to increase the sensitivity to the Cortical closures through the transient resistances of the discharge junction from the load modes, the series-connected logical element OR and the reacting organ, the output of which is connected, is additionally introduced to the input of the switching unit of the response characteristics of the resistance relay, and the output of the bKD element of the formation of mismatch impulses (coincidental) pulses of the instantaneous electrically values is also connected to the input corresponding to the newly introduced aemu OR gate.

Sources of information taken into account in the examination

1. Fedoseev A.M. Relena protection of electrical systems. M., Energie, 1976, p. 213.

2. In the same place 258-259, fig. 4-36.

Claims (1)

Claim A device for a high-speed step of distance protection, containing three resistance relays, each of which is made in the form of successively connected units for the formation of compared values, an element for generating mismatched (coincident) signs of instantaneous electrical quantities and a reacting organ, a switching unit of characteristics, operation of the resistance relay, outputs which are connected to the corresponding inputs of the units of formation of the compared values, and a logical element OR connected by inputs to the output there is a resistance relay and the output of which is the output of the device, characterized in that, in order to increase the sensitivity to short circuits through transient resistances while ensuring detuning from load conditions, an OR logic element and a reacting organ are added in series, the output of which is connected to the input of the switching unit ha-. the characteristics of the operation of the resistance relay, and the output of each element of the formation of pulses of mismatch (coincidence) of signs of instantaneous electrical quantities is also connected to the corresponding input of the newly introduced logical element OR.