JP5534757B2 - Current differential relay - Google Patents

Description

  The present invention relates to a current differential relay device used for power transmission line protection of a power system.

  The power transmission line protection relay device obtains information on the amount of electricity in the power system from an instrument transformer, detects an accident in the power transmission line, and outputs an interruption command to the circuit breaker to remove the accident. On the other hand, a continuous current interrupting arc horn has recently been developed that can recover from an accident in a transmission line in a short time of about half a cycle. In the transmission line using this continuity interruption type arc horn, if this works and the arc is successfully extinguished, the control to lock the interruption command from the transmission line protection relay device is performed. It is required to cut off the transmission line promptly.

  As countermeasures against this, the power transmission line protection relay device has an operation delay due to a timer, and, as shown in Patent Document 1, a continuity interruption type arc based on the amount of electricity and the combined amount of electricity previously taken into the power transmission line protection relay device. A method has been proposed in which the operation of the horn is detected so that the transmission line protection relay device does not perform unnecessary control.

JP 2004-274840 A

  However, since the influence of the load current flowing in the transmission line is not considered in the operation detection circuit of the continuous current interruption type arc horn as disclosed in Patent Document 1, the continuous current interruption type arc horn is used in the case of a heavy load transmission line. There is a problem that it becomes difficult to identify the movement of the camera.

  The present invention has been proposed in order to solve the problems of the prior art as described above, and its object is to reliably determine the operation of the continuity interruption type arc horn and to detect the continuity interruption type arc. An object of the present invention is to provide a highly accurate current differential relay device capable of performing transmission line interruption due to failure of arc extinguishing of a horn at higher speed than control by a conventional interruption circuit using a timer.

In order to solve the above-described problems, the present invention provides an internal fault determination means for determining an internal fault of a current differential relay in a current differential relay device for a transmission line equipped with a continuous current interrupting arc horn. A differential current detecting means for detecting a differential current of a dynamic relay; an arc horn operation determining means for determining an operation of the continuity interrupted arc horn; and an accident phase for detecting an arc extinction failure phase of the continuity interrupted arc horn Current differential relay lock determination means for determining whether to lock the output of the internal accident determination means based on the results of the detection means, the difference current detection means, the arc horn operation determination means and the accident phase detection means; A current differential relay output effective control means for releasing the lock of the output of the internal accident determination means is provided. Further, as the arc horn operation determining means, means for detecting a decrease in the difference current of the current differential relay is used.

  According to the present invention having the above-described configuration, when an accident occurs in a power transmission line equipped with a continuity interruption type arc horn, the current differential relay lock determination means detects it faster than the internal accident determination means. Based on the output of the differential current detection means that performs the control, the internal accident determination means can be controlled to lock for a predetermined time.

  In addition, because the differential current that is not affected by the load current is used to determine the operation of the continuous current interrupting arc horn, even with heavy load transmission lines, which were difficult to determine the operation of the continuous current interrupting arc horn, It is possible to perform an operation determination. As a result, the interruption operation when the continuity interruption arc horn fails can be performed at high speed.

  According to the present invention as described above, the operation of the continuity interruption type arc horn is reliably determined, and the transmission line interruption due to the arc extinguishing failure of the continuity interruption type arc horn is determined by the interruption circuit using the conventional timer. A highly accurate current differential relay device that can be performed at a higher speed than the control can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the current differential relay apparatus which concerns on this invention, Comprising: (A) is a figure which shows a basic structure, (B) is a figure which shows the specific example of the arc horn operation | movement determination means in Example 1. FIG. . It is a figure which shows the specific example of the current differential relay lock determination means in Example 1 of the current differential relay apparatus which concerns on this invention. 3 is a time chart illustrating an operation of a current differential relay lock determination unit according to the first embodiment. It is a figure which shows the specific example of the arc horn operation | movement determination means in Example 2 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the current differential relay lock determination means in Example 2 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the arc horn operation | movement determination means in Example 3 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the accident phase detection means in Example 4 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the other specific example of the accident phase detection means in Example 4 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the other specific example of the accident phase detection means in Example 4 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the current differential relay output effective control means in Example 5 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the current differential relay output effective control means in Example 6 of the current differential relay apparatus which concerns on this invention. It is a figure which shows the specific example of the current differential relay output effective control means in Example 7 of the current differential relay apparatus which concerns on this invention.

  Embodiments of a current differential relay device according to the present invention will be described below with reference to the drawings.

(1-1) Configuration of Embodiment 1 This embodiment shows a basic configuration of a current differential relay device according to the present invention and a specific example thereof. That is, as shown in FIG. 1A, the current differential relay device according to the present embodiment detects an internal fault determination unit 1 that determines an internal fault of the current differential relay and a differential current between the current differential relays. Differential current detecting means 2 for performing, arc horn operation determining means 3 for determining the operation of the continuous current interrupted arc horn, and accident phase detecting means 4 for detecting the arc extinction failure phase (accident phase) of the continuous current interrupted arc horn. It has.

  Further, current differential relay lock determination for determining whether or not to limit (lock) the output of the current differential relay based on the results of the differential current detection means 2, arc horn operation determination means 3 and accident phase detection means 4. Means 5 and current differential relay output valid control means 6 for validating the output of the current differential relay when a predetermined requirement is satisfied, as shown in the figure by an OR circuit 7 and an AND circuit 8 It is connected.

  In FIG. 1, fail-safe and other necessary circuits configured as a current differential relay device are omitted because they are not involved in the description of the present invention. Further, in this embodiment, as shown in FIG. 1B, as a specific example of the arc horn operation determining means 3, a difference current decrease detecting means 200 for detecting a decrease in the difference current of the current differential relay is used. And As a method of detecting the difference current difference, for example, the difference between the current difference currents is obtained from the difference current one cycle before, and when the difference is equal to or greater than a predetermined value, it is determined as “decrease”. The predetermined value K is α% of the value of the difference current one cycle before (0 <α <100%).

  FIG. 2 shows a specific example of the current differential relay lock determination means 5. That is, the differential current detection means 2 is connected to the off-delay timer 102 via the NOT circuit 101 and further connected to the OR circuit 106 via the NOT circuit 103. The difference current decrease detecting means 200 is connected to the AND circuit 105 via the NOT circuit 104, and the accident phase detecting means 4 is connected to the AND circuit 105. The AND circuit 105 is connected to the OR circuit 106. It is connected.

(1-2) Operation of Embodiment 1 The present embodiment having the above-described configuration operates as shown in the time chart of FIG. That is, when an accident occurs in a power transmission line equipped with a continuity interruption type arc horn, the current differential relay lock determination means 5 determines whether an internal accident has occurred in anticipation of successful extinction by the continuity interruption type arc horn. Based on the output of the differential current detection means 2 that performs detection at a higher speed than the means 1, the internal accident determination means 1 is connected to the off-delay timer 102 by the NOT circuit 101, the off-delay timer 102, the NOT circuit 103 and the OR circuit 106. Lock for a predetermined time (tmS).

  In addition, as shown in FIG. 2, when the differential current decrease detection means 200 and the accident phase detection means 4 are established by the AND circuit 105, it is determined that the accident extinction can be performed by the continuity interruption type arc horn, and the off-delay timer 102 During the predetermined time, an unnecessary shut-off command is not output.

  If the difference current decrease detecting means 200 and the accident phase detecting means 4 are not established in the AND circuit 105 after a predetermined time of the off-delay timer 102, it is determined that the accident-extinguishing cannot be performed by the continuous current interrupting arc horn. After a predetermined time of the timer 102, the internal accident determination means 1 is operated to output a cutoff command. Further, when a predetermined requirement of the current differential relay output effective control means 6 is established, for example, when a predetermined time has elapsed since the occurrence of an accident, the internal accident determination means 1 is unlocked to prepare for accident interruption.

(1-3) Effect of Example 1 According to the present example as described above, in the current differential relay device used in the transmission line in which the continuous current interrupting arc horn is installed, the influence of the load current is reduced. Because the differential current that is not received is used to determine the operation of the continuous current interrupting arc horn, it is possible to determine the operation at high speed even with heavy load transmission lines that were difficult to determine the operation of the continuous current interrupting arc horn. It becomes. As a result, the interruption operation when the continuity interruption arc horn fails can be performed at high speed.

(2-1) Configuration of Embodiment 2 This embodiment is a modification of Embodiment 1 described above. As shown in FIG. 4, each phase difference current decrease detecting means 201 is used as the arc horn operation determining means 3. It was. The focus is on the point that the fault current disappears and the difference current of each phase decreases when the interrupted arc horn operates and succeeds in extinguishing the arc. As a method for detecting a difference current decrease, for example, a difference between current phase difference currents is obtained from each phase difference current one cycle before, and when the difference is equal to or greater than a predetermined value, it is determined as “decrease”. The predetermined value K is α% of the value of the difference current one cycle before (0 <α <100%).

  FIG. 5 shows a specific example of the arc horn operation determining means 3, the accident phase detecting means 4 and the current differential relay lock determining means 5 in the present embodiment. That is, as in the first embodiment, the difference current detecting means 2 is connected to the off-delay timer 102 via the NOT circuit 101 and further connected to the OR circuit 106 via the NOT circuit 103. Further, each phase difference current decrease detecting means 202 to 204 which is the arc horn operation determining means 3 is connected to the AND circuits 214 to 216 via NOT circuits 211 to 213, respectively, and each phase which is the accident phase detecting means 4 Accident detection means 205 to 207 are connected to the AND circuits 214 to 216, and these AND circuits 214 to 216 are connected to the OR circuit 217. Further, the OR circuit 217 is connected to the OR circuit 106.

(2-2) Operation of Example 2 In the present example having the above-described configuration, when an accident occurs in a power transmission line equipped with a continuity interruption type arc horn, In the current differential relay lock determination means 5, the NOT circuit 101, the off-delay timer 102, the NOT circuit 103, and the OR circuit 106 are based on the output of the difference current detection means 2 that performs detection faster than the internal accident determination means 1. The internal accident determination means 1 is locked for a predetermined time of the off-delay timer 102.

  Further, depending on the operating conditions of each phase difference current decrease detecting means 202 to 204 and each phase fault detecting means 205 to 207, the NOT circuit 211 to 213, the AND circuits 214 to 216 and the OR circuit 217 are used to interrupt the continuous current of each phase. The operating result of the horn is detected. Then, when the malfunction of the continuous current interrupting arc horn is detected even in one of the accident phases, the lock is released by the AND circuit 8 and the internal accident determining means 1 is promptly interrupted. On the other hand, when the operation of the continuous current interruption type arc horn is detected in all the accident phases, the internal accident determination means 1 is locked by the AND circuit 8 and unnecessary interruption is not performed.

(2-3) Effects of Second Embodiment According to the present embodiment as described above, in addition to the effects of the first embodiment, the continuous current cut-off type is obtained with each phase difference current generally required for a current differential relay. Since the operation determination of the arc horn is performed, it is not necessary to install a dedicated operation determination relay for the continuous current interrupted arc horn.

(3-1) Configuration of Embodiment 3 This embodiment is a modification of Embodiment 1, and as shown in FIG. 6, zero phase difference current decrease detection means 301 is used as the arc horn operation determination means 3. It was. The focus is on the point that the accidental current disappears and the zero phase difference current decreases when the continuous current interrupted arc horn operates and the arc is successfully extinguished. In addition, the current differential relay of the high resistance grounding system adopts the judgment method based on the zero phase difference current because it is difficult to judge the accident by each phase difference current due to the relation of the accident detection sensitivity at the time of 1-line ground fault. is there.

  As a detection method of the zero phase difference current decrease, for example, a difference of the current zero phase difference current is obtained from the zero phase difference current one cycle before, and when the difference is equal to or larger than a predetermined value, it is determined as “decrease”. The predetermined value K is α% of the value of the zero phase difference current one cycle before (0 <α <100%).

(3-2) Actions and effects of the third embodiment The present embodiment having the above-described configuration operates in the same manner as the second embodiment, and is a zero phase difference current generally required for a current differential relay. Therefore, it is not necessary to install a dedicated operation determination relay for the continuous current interrupting arc horn.

(4-1) Configuration of Embodiment 4 This embodiment is a modification of Embodiment 1 described above, and detects an arc-extinguishing failure phase of a continuity interruption type arc horn as shown in FIGS. As the accident phase detection means 4, the phase voltage drop detection means 401 to 403, the phase overcurrent detection means 411 to 413, or the distance relay means 421 to 423 are used. In addition, although the said each means may be a single structure, the structure by a some combination may be sufficient.

(4-2) Operation of Embodiment 4 The present embodiment having the above-described configuration operates as follows. First, as shown in FIG. 7, when each phase voltage drop detecting means 401 to 403 is used as the accident phase detecting means 4, for example, the voltage value Va of the A phase voltage drop detecting means 401 is set to a predetermined value set in advance. When Vk or less, it is determined that the A phase is the accident phase. The predetermined value Vk is α% of the rated voltage (0 <α <100%).

  As shown in FIG. 8, when each phase overcurrent detection means 411-413 is used as the accident phase detection means 4, for example, the current value Ia of the A-phase overcurrent detection means 411 is a predetermined value set in advance. When it is Ik or more, it is determined that the A phase is the accident phase. The predetermined value Ik is α% of the rated current (α> 100%).

  As shown in FIG. 9, when distance relay means 421 to 423 are used as the accident phase detection means 4, for example, when the impedance Zab of the AB phase distance relay means 421 is equal to or greater than a predetermined value Zk set in advance. A and B phases are determined to be accident phases. The predetermined value Zk is α% of the protection target impedance (α> 100%).

(4-3) Effects of Embodiment 4 As described above, according to the present embodiment, the fault phase detection is performed by at least one of the voltage drop detection means, the overcurrent detection means, and the distance relay means, in other words, the terminal By detecting the accident phase based on the magnitude of the impedance obtained by using the voltage, the terminal current, or the terminal voltage and the terminal current, the same effect as in the first embodiment can be obtained.

(5-1) Configuration of Embodiment 5 In this embodiment, as shown in FIG. 10, the current differential relay output effective control means 6 is turned on after a predetermined time of the operation of the internal fault determination means 1 of the current differential relay. In this configuration, the output of the internal accident determination means 1 is validated. In the figure, reference numeral 502 denotes an on-delay timer.

(5-2) Effects and Effects of Embodiment 5 In this embodiment, the output of the internal accident determination means 1 is validated by the on-delay timer 502 after a predetermined time has elapsed since the operation of the internal accident determination means 1. The
Thus, in the present embodiment, the use of the operation signal of the internal accident determination means 1 can block the continuation of the accident regardless of the result of the current differential relay output control.

(6-1) Configuration of Embodiment 6 In this embodiment, as shown in FIG. 11, the current differential relay output effective control means 6 is set to an internal accident determination means after a predetermined time of the operation of the accident phase detection means 4. 1 is made effective. In the figure, reference numeral 602 denotes an on-delay timer. The accident phase detection means 4 may be the system shown in FIGS. 7, 8, and 9 of the fourth embodiment.

(6-2) Effects and Effects of Embodiment 6 In this embodiment, the output of the internal accident determination means 1 is validated by the on-delay timer 602 after a predetermined time has elapsed since the accident phase detection means 4 has been operated. The
Thus, in the present embodiment, the use of the operation signal of the accident phase detection means 4 can block the continuation of the accident regardless of the result of the relay output control circuit.

(7-1) Configuration of Embodiment 7 In this embodiment, as shown in FIG. 12, the current differential relay output effective control means 6 is changed to a differential current detected by the differential current detection means 2 of the current differential relay. When the value is equal to or greater than the rated current for extinguishing the arc of the continuous current interrupting arc horn, the output of the internal accident determination means 1 is made valid.

(7-2) Effects and effects of Embodiment 7 In this embodiment, when the difference current value obtained by the difference current detection means 2 of the current differential relay is equal to or greater than a predetermined value (Idk) set in advance. The output of the internal accident determination means 1 is validated. The predetermined value Idk is α% (α> 100%) of the arc extinguishing rated current value of the continuous current interrupted arc horn.
As described above, in this embodiment, when the difference current value obtained by the difference current detecting means 2 of the current differential relay is equal to or higher than the arc extinguishing rated current of the continuous current interrupting arc horn, the determination of the relay output control circuit is performed. It can be blocked regardless of the result.

DESCRIPTION OF SYMBOLS 1 ... Internal accident determination means 2 ... Difference current detection means 3 ... Arc horn operation determination means 4 ... Accident phase detection means 5 ... Current differential relay lock determination means 6 ... Current differential relay output effective control means 7 ... OR circuit 8 ... AND circuit 200... Difference current decrease detection means 201. Each phase difference current decrease detection means 202... A phase difference current decrease detection means 203... B phase difference current decrease detection means 204... C phase difference current decrease detection means 205. B phase accident detection means 207 ... C phase accident detection means 301 ... Zero phase difference current decrease detection means 401 ... A phase voltage drop detection means 402 ... B phase voltage drop detection means 403 ... C phase voltage drop detection means 411 ... A phase overcurrent Detection means 412 ... B phase overcurrent detection means 413 ... C phase overcurrent detection means 421 ... AB phase distance relay means 422 ... BC phase distance relay means 423 ... CA phase distance relay means

Claims (8)

In the current differential relay device of the transmission line equipped with the continuous current interrupting arc horn,
An internal accident determination means for determining an internal accident of the current differential relay;
Differential current detection means for detecting the differential current of the current differential relay;
Arc horn operation determining means for determining the operation of the continuous current interrupted arc horn;
Accident phase detection means for detecting the arc extinction failure phase of the continuity interruption type arc horn,
Current differential relay lock determination means for determining whether or not to lock the output of the internal accident determination means based on the results of the differential current detection means, arc horn operation determination means and accident phase detection means;
A current differential relay device comprising current differential relay output effective control means for releasing the lock of the output of the internal accident determination means .   The current differential relay device according to claim 1, wherein the arc horn operation determining means is configured by means for detecting a decrease in a difference current of a current differential relay.   The current differential relay device according to claim 1, wherein the arc horn operation determining means is configured by means for detecting a decrease in a difference current of each phase of the current differential relay.   The current differential relay device according to claim 1, wherein the arc horn operation determining means is configured by means for detecting a decrease in zero phase difference current.   5. The accident phase detection means according to claim 1, wherein the accident phase detection means comprises at least one of a phase voltage drop detection means, a phase overcurrent detection means, or a distance relay means. The current differential relay device described in 1. 6. The current differential relay output valid control means releases the lock of the output of the internal accident determination means after a predetermined time from the operation of the internal accident determination means . The current differential relay device according to any one of the above. 6. The current differential relay output effective control means releases the lock of the output of the internal accident determination means after a predetermined time from the operation of the accident phase detection means. The current differential relay device according to any one of the above. The current differential relay output effective control means releases the lock of the output of the internal accident determination means when the differential current value of the current differential relay is equal to or greater than the arc extinguishing rated current of the continuity interruption type arc horn. The current differential relay device according to any one of claims 1 to 5, wherein the current differential relay device is provided.

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