SU1513559A1 - Redundancy arrangement for switch failure - Google Patents

Abstract

The invention relates to electrical engineering and can be used in relay protection against short-circuiting of 110 kv electrical installations. The aim of the invention is to extend the functionality by ensuring operability in the repair of the switch of the electrical substation according to the bridge scheme. The device uses three logic blocks (according to the number of switches), two of which have introduced repair mode relays. When one of the switches is repaired, the start-up logic circuits and the output circuits of the fail-safe switch device automatically switch so that the device continues to operate, and when a short-circuit occurs. and the failure of one of the remaining switches provides redundancy shutdown short-circuit. with high sensitivity and speed. 1 il.

Description

The invention relates to electrical engineering and can be used in short-circuit relay protection of electrical installations 110 kV and above.

The aim of the invention is to extend the functionality by ensuring operability during switch repair.

The drawing shows a block diagram of the device.

The backup device in case of a substation switch failure with two

power lines and two power transformers, connected according to the scheme of a bridge of three switches, two of which are in the circuit of the corresponding line, with 3amjiTbi relay blocks on each line and each power transformer contain three logical blocks 1-3, one on each switch. Each of the logical blocks 1 (2 and 3) includes the first element OR 4 (5 and 6), the first element AND 7 (8 and 9), the second element

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OR 10 (ll and 12), the second element is AND 13 (14 and 15) and the third element is OR 16 (17 and 18), to which the device start circuits are connected. In addition to the enumerated elements, each logical block 1 (2 and 3) includes the element 19 (20 and 21) of time, the third element I 22 (23 and 24) with the first output element 25 (26 and 27) connected to its output, the fourth element is And 28 (29 and 30) with the second output element 31 (32 and 33) connected to its output, the fifth element And 34 (35 and 36) with the third output element 37 connected to its output 37 (38 and 39) , the sixth element And 40 (41 and 42) with the fourth output element 43 (44 and 45) connected to its output. The output elements of each logical block are connected to the executive circuits of the device: the disconnecting circuits of the corresponding line and power transformer, the stopping circuits of the high-frequency current protection transmitter of the corresponding line, the transmitting circuits of the disconnecting signal of the corresponding line and the prohibition circuit The automatic reclosing circuit breaker of the corresponding line, In the starting circuits of each logic block 1 (2 and 3) current relays 46 (47 and 48) are installed, the inputs of which are intended to be connected to the secondary winding of the current transformer in the circuit according to stvuyuschego switch and relay switch control corresponding to the position of 49 (50 and 51) In this case, logical units 1 and 2 are respectively provided with relays 52 and 53 of the repair mode with two normally open contacts each Tammy. The first closures contacts 54 and 55, respectively, of the repair mode relay 52 and 53 connect the inputs of the second output elements 31 and 32 of the first and second logic blocks, and the second make contacts 56 and 57 respectively, of the repair mode relay 52 and 53 connect the corresponding inputs of the first elements OR 4 and 5,

The device operates as follows.

If there is a short circuit on line L 1 and its switch fails, the signal from protection blocks L1 through the first element OR 4 is fed to one input of the first element AND 7, the other inputs of which receive signals from the current relay 46 and the control unit of the switch 49, which leads to

the appearance of the signal at the output of the first element AND 7, in which the first element OR 4 is self-retained, which fixes the start signal when the relay protection is momentarily triggered, and the time element 19 is started through the second element OR 1. After a time delay, which is chosen in the order of 0.25-0.3 s, the third 22, fourth 28, fifth 37 and sixth 40 elements AND are triggered, as a result of which the device operates to disconnect the adjacent switch and power transformer.

In repair mode, when one of the linear switches is removed from the bridge circuit and the jumper repair between both lines is turned on, the relay mode 52 and 53 are automatically connected to the operating current source,

During the repair of the switch L1 and short circuit on this line, accompanied by the failure of the switch L2, from the protection blocks L1 through the closed contacts 56, 57 and 58, 59, relay 52 and 53 the signal goes through the first element OR 5 of the second logical block to the first input element And 8, on the other two inputs of which there are also signals from. relay 47 of current and switch position switch 50, After element 4 of the second logic block triggers its output 29 through contact closed when repair relay 52 and 53 contacts 55 are connected to the input of the second output 31 of the first logic block, the additional action of the device is not different from described. At repair of switch L2 and short circuit on this line, accompanied by failure of switch L1, from protection blocks L2 through contacts 56, 57 and 58, 59, relay 52 and 53, the signal goes to the inputs of the first element OR 4 of the first logic unit and further operation of the device occurs similar to that described. Consequently, the operability of the failover backup device during the repair of one of the linear switches is maintained, which indicates the achievement of the set goal and thank you, which maintains the speed and sensitivity of the damage shutdown during the repair scheme.

5.5

A fail-safe switch device, implemented using the described unified logic blocks installed according to the number of switches, can also be applied to other substation wiring diagrams.

Claims (1)

Invention Formula A backup device in case of a substation switch failure with two power transformers connected according to the bridge scheme of three switches, two of which are in the circuit of the corresponding line, with relay protection blocks on each line and each power transformer, containing for each switch a switch for controlling the position of the switch, relay current, the input of which is intended to be connected to the secondary winding of a current transformer in a circuit of a switch, and a logic unit made in the form of six AND elements, three OR elements, an element time and four output elements, the output of the current relay is connected to the first inputs of the first and second elements AND, the output of the switch position control unit is connected to the second input of the second element AND, the output of the first element AND is connected to the first input of the first element OR, the output of the second element And is connected to the first input of the second element OR, the output of the third element OR is connected to the third input of the second element AND, the output of the time element is connected to .connected by the first inputs of the third and fourth elements AND, the outputs of which are connected to the inputs of the first and second output elements respectively, the first input of the fifth element AND is connected to the first input of the third element OR, the second input of which is connected to the second input of the fourth element AND, the fifth element And is connected to the input of the third output element, the output of the sixth element And is connected to the input of the fourth output element, characterized in that, in order to extend the functionality by providing otosposobnosti for repair of the circuit breaker, said logical unit is installed on each switch, the second input of the first ele559 5 OR is combined with the first input of the sixth element AND, the second input of which is combined with the input of the first output element, the output of the first element OR is connected to the second input of the first element AND, the third input of which is combined with the second input of the second element AND, the output of the first element AND connected to merged. the second inputs of the second element OR and the third element AND, the output of the second element OR are connected to the input of the time element, the output of the second element 5 AND is connected to the second input of the fourth element AND, the output of which is connected to the second input n -. That element And, prn it in the first and the second logic blocks are entered 0 repair mode relay, the winding of which is connected to the operating current source through the closing contact of the repair mode switch, the first closing contact of the repair mode relay 5 of the first logic unit combines the first input of the second output element of the first logic unit with the second input of the second output element the second logic block, and the first closing contact of the repair mode relay of the second logic block combines the second input of the second output element o logical block with the second input of the second output element of the first logical block, the second and third inputs of the first element OR are designed to connect to the outputs of the first and second Q protection blocks of the corresponding line respectively, the first and third inputs of the second element OR are intended to be connected: the outputs of the first and second protection blocks, respectively, of the corresponding power transformer, the second closing contact of the repair mode of the first logic block, is designed to combine the output in the first protection blocks of both Q lines, the second closing contact of the repair mode relay of the second block is designed to combine the outputs of the second protection blocks of both lines; in the third logic block e, the second and third inputs of the first element OR, respectively, are the same and connected to the outputs of the first and the second protection blocks of the first power transformer, and per5 1513559. eight the left n the third head of the OR element of the second power unit protection blocks are assigned to be connected to the outputs of the spformer  I sootveitino first and second trance