JPH0767235B2 - Protective relay method for remote multi-circuit switch measurement controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a distribution line system using a multi-circuit switch,
When a ground fault or short-circuit accident occurs, the faulty section is detected, the switch in the faulty section is kept open, and the switch in the sound section is remotely turned on to disconnect the faulty section. Regarding relay method.

[Conventional technology]

In general, a remote multi-circuit switch measurement control device is constructed, for example, as shown in FIG. In the figure,
(1) is a substation, (2) and (3) are regular and standby lines that are three-phase distribution lines from the substation (1), (4),
(5) is a circuit breaker for the distribution line on the regular side and a circuit breaker for the distribution line on the standby side provided on the regular line (2) and the standby line (3) respectively, and (6) and (7) are power source transformers. (Hereinafter referred to as PT), the primary side is the regular line, the standby line (2),
It is connected to (3).

(8) and (8) are current transformers (hereinafter CT) provided for two phases of the three-phase load distribution line from both circuit breakers (4) and (5) to the main line of the latter-stage multi-circuit switch. , (9) is a zero-phase current transformer (hereinafter referred to as ZCT) provided on the load distribution line,
(10) is a zero-phase transformer (hereinafter referred to as ZPD) whose primary side is connected to the load distribution line, (11) is a regular-preliminary switching device, and the secondary side of both PTs (6) and (7). The power supply section (11a) that uses the output as the input power source, the measurement section (11b), and the short-circuit relay [51
S] and ground fault direction relay [67G] protective relay (11
c) and the control unit (11d) of both circuit breakers (4) and (5).

When the short-circuit current detected by CT (8) matches the detection characteristic of the short-circuit relay [51S] of the protective relay (11c) that has been set in advance, the control unit (11d) causes the closed circuit breaker (4 ) Or (5) is tripped, and the zero-phase current detected by ZCT (9), the zero-phase voltage detected by ZPD (10), and the phase difference between the zero-phase current and the voltage are set in advance. When the detection characteristic of the ground fault direction relay [67G] of the electric section (11c) is met, the control section (11d) trips the circuit breaker (4) or (5) in the closed state.

Further, in FIG. 3, (12) is a trunk line connected to the load distribution line, and (13a) and (13b) are two electromagnetic closing / non-voltage trip type provided at both ends of the trunk line (12). Trunk switch, (14) is a branch circuit of four circuits branched from the trunk line (12) between both trunk switch (13a), (13b) and connected to each customer, (15) is each branch line ( Four branch line switches of the electromagnetic closing and non-voltage trip type provided in 14),
(16) is two PTs whose primary side is connected to both ends of the trunk line (12).

At this time, the closing coils of the switches (13a), (13b), (15) that use the secondary side output of the PT (16) as a power source are automatically turned on under the condition that there is a power supply voltage, and the main line (12 ), The switches (13a), (13b) and (15) are tripped. Both main line switches (13a), (13
b) and each branch line switch (15) constitute a multi-circuit switch.

(17) is both ends of the main phase (12) for two phases and each branch line (1
CT provided in each of the two phases of 4), (18) is the main line (1
Z provided at both ends of 2) and each branch line (14)
CT, (19) is a ZPD provided on both ends of the trunk line (12) and each branch line (14) for the primary side, and (20) is a multi-circuit control device, and the secondary side output of the PT (16) Power supply section (20a) that uses the input power as input, measuring section (20b), and short-circuit relay [51S]
And protective relay (20c) consisting of a ground fault direction relay [67G]
And the control unit (20) of each switch (13a), (13b), (15)
d) consists of

When a short circuit or a ground fault occurs on the multi-circuit switch side, the short circuit current [51S] of the protective relay (20c) with the short circuit current detected by each CT (17) set in advance is detected. If it conforms to, each switch (13a),
(13b) and (15) are closed and locked, and the zero-phase current detected by ZCT (18), the zero-phase voltage and zero-phase current detected by ZPD (19), and the phase difference between the voltages are preset. When the detection characteristics of the ground fault direction relay [67G] of the protective relay section (20c) are met, the control section (20d) causes each switch (13a), (13
b) and (15) are input locked.

By the way, a slave station is constituted by a multi-circuit switch composed of the above-mentioned both main line switches (13a), (13b) and each branch line switch (15), and a multi-circuit control device (20). In the case of two, two slave stations (# 1) and (# 2) are provided, and, like the above-mentioned normal side and standby side circuit breakers (4) and (5) for distribution lines, regular and standby Line (2),
(3) are provided with other breakers (4), (5) for distribution lines on the regular side and the spare side, respectively, and both breakers (4), (5) for other distribution lines and the other child The main line (12) of the multi-circuit switch of the station (# 2) is connected by a load distribution line, and the negative distribution line is provided with CT (8), ZCT (9), ZPD (10),
Another regular-standby switching device is provided for both slave stations (# 1),
The main lines (12) of the multi-circuit switch of (# 2) are connected to each other.

And the regular line (2), when the standby line (3) is energized,
When a ground fault occurs on the side of the multi-circuit switch, both circuit breakers (4) or (5) for distribution lines provided in the energized circuit trip, and the energized line and main line (12) become unvoltage. Then, all the switches in the closed state are pulled out, and after a certain period of time, the circuit breakers (4) or (5) are closed again.

On the other hand, zero-phase current detected by each ZCT (18), each ZPD
The zero-phase voltage, zero-phase current, and phase difference of the voltage detected by (19) are respectively measured by the measuring unit (20b), and each measured value is set in advance in the ground fault direction of the protective relay unit (20c). When the detection characteristics of the relay [67G] are met, the ground fault direction is detected, the corresponding zero-phase current, zero-phase voltage and ZCT (18) and ZPD (19) that give the phase difference are specified, and the fault section is identified. The switch in the detected accident section is detected by the control unit (20
It is closed and locked by d).

On the other hand, the switches in other sections are automatically turned on by the recovery of the voltage of the distribution line, and the switches in the sound section except the switch in the accident section where the closing is locked are automatically turned on, and the energization circuit is reset again. The closed circuit realizes power transmission to the healthy section and disconnects the accident section.

Even when a short circuit accident occurs on the multi-circuit switch side, the accident section is similarly separated.

[Problems to be Solved by the Invention]

However, in this case, the protection relay section (20c) of the slave stations (# 1) and (# 2) has a short circuit relay [51c] that requires coordinated operation adjustment.
S] and the ground fault direction relay [67G] are used, the detection characteristics such as sensitivity and operation time limit of these protective relays are adjusted for each protective relay section (2c) when the system is changed due to the increase of customers. It has to be fixed, is extremely complicated, requires a lot of labor and time, and there is a problem that it is not possible to easily cope with a system change in operation.

Therefore, the present invention has been made with the above points in mind, and enables detection and disconnection of an accident section without using a protective relay that requires coordinated operation adjustment as in the prior art, and facilitates system change. The purpose is to

[Means for Solving the Problems]

And, as a means for achieving the above purpose, a main line switch provided on a main line connected to a distribution line, and a branch line provided on each of a plurality of branch lines branched from the main line and connected to each consumer. A plurality of slave stations are respectively provided with switches and detection means for detecting the ground fault current and the short-circuit current, which are provided on the main line and the branch lines respectively, and the ground based on the ground fault, the short-circuit current, etc. by the detection means is provided. When a fault or short circuit accident is detected, the switch in the accident section is held open and the master station
In a protective relay method for a remote multi-circuit switch measurement control device that remotely turns on the switch in a sound section, in the present invention, each of the slave stations detects a short circuit current and a ground fault current that exceed a threshold value. A measurement unit, a first non-volatile memory that stores a short-circuit current value, and a second non-volatile memory that stores a ground-fault current value are provided, and in each of the slave stations, only a current value of a ground fault or a short-circuit fault is provided. Detected and stored, the master station remotely turned on the main switch to perform trial power transmission, and transmitted the stored current values of both memories to the master station to create a fault current distribution pattern A feature is characterized in that an accident section is detected from the accident current distribution pattern, and the switch in a sound section other than the detected accident section is remotely turned on by the master station to disconnect the accident section.

[Action]

Therefore, according to the present invention, when a short circuit or a ground fault occurs on the multi-circuit switch side of each slave station, in each slave station, only the short-circuit current and the ground fault current of the trunk line and each branch line are measured by the measuring unit. The detected short circuit current value and ground fault current value are stored in the first and second nonvolatile memories.

Then, the main station remotely turns on the main switch to perform trial power transmission of the main line.

Further, by polling from the master station, the short-circuit current value and ground fault current value stored in both memories of each slave station are transmitted to the master station.

Further, in the master station, a short-circuit current distribution pattern and a ground fault current distribution pattern are created based on both current values transmitted from each slave station, an accident section is detected from the created pattern, and the detected accident section is detected. The switch of the healthy section except for is remotely turned on by the master station, and the accident section is disconnected.

In this case, it is possible to detect and disconnect the fault section by detecting only the short-circuit current and the ground fault current without using a protective relay that requires coordinated operation adjustment as in the conventional case.

〔Example〕

Next, the present invention will be described in detail with reference to FIGS. 1 and 2 showing one embodiment thereof.

In FIG. 1, the same symbols as in FIG. 3 indicate the same or corresponding ones, and the difference from FIG. 3 is that both slave stations (#
1) and (# 2) ZPD (19) is removed, and the protective relay section (2c) of the multi-circuit control device (20) is removed, and the multi-circuits of both slave stations (# 1) and (# 2) are removed. Each CT in the control device (20)
A first non-volatile memory (hereinafter referred to as a first memory) (21a) that stores the short-circuit current value detected by (17) and measured by the measurement unit (20b) is provided, and
A second non-volatile memory (hereinafter referred to as a second memory) (21b) that stores the ground fault current value detected by each ZCT (18) and measured by the measurement unit (20b) is provided, and both slave stations ( # 1), (# 2) multi-circuit controller (20)
In addition, both memories (21a), (2
The point is that a transmission unit (23) for transmitting the stored data of 1b) via the communication line (22) is provided.

At this time, each CT (17), each ZCT (18) and measurement unit (20b)
The detection means is constituted by the.

When a short circuit or a ground fault occurs on the multi-circuit switch side when the service line (2) or the protection line (3) is energized,
Both circuit breakers (4) or (5) for distribution lines installed in the line being energized trip, and the energizing line and the main line (12) are operated without voltage and all the switches in the closed state are tripped. Is
After a certain period of time, the circuit breaker (4) or (5) is closed again.

On the other hand, the short-circuit current value detected and measured by each CT (17) and measurement unit (20b), or each ZCT (18) and measurement unit (2
The ground fault current value detected and measured by 0b) is stored in the first memory (21a) or the second memory (21b) before the circuit breaker (4) or (5) for the distribution line is interrupted. It

Next, the master station sequentially turns on the main line switches (13a) and (13b) from the host, performs the trial power transmission of the main line (12), restores power to both multi-circuit control units (20), and By polling from the station, the short-circuit current value or the ground fault current value stored in the first memory (21a) or the second memory (21b) of both multi-circuit control devices (20) is transferred to the transmission section (23) and the communication line ( 22) and is transmitted to the master station, and the master station creates a short-circuit current distribution pattern or a ground fault current distribution pattern.

By the way, for example, the ground fault accident points A to G in FIG.
Of each main station and the main switch (13
a) is a detecting means for detecting the ground current of the upper trunk line provided with # 1-1, and a detecting means for detecting a fault current of each branch line provided with each branch line switch (15) # 1-6, # 1-3, # 1-4, # 1-5 from the top, and a detection means for detecting a fault current in the main line provided with the main line switch (13b). Similarly, for the other slave station (# 2), the detection means for detecting the fault current of each line are # 2-1 to # 2-6, and the detection means higher than these slave stations are # 0. , When a ground fault occurs at each of the virtual accident points A to G, the detection means # 0, # 1-1 to # 1-6,
A ground fault current distribution pattern showing whether or not a ground fault current of a threshold value or more flows in # 2-1 to # 2-6 is as shown in FIG.

However, the diagonal lines in FIG. 2 indicate that a current equal to or greater than the threshold value is flowing, and in FIG. 1, both the breakers (4) for distribution lines on the slave station (# 2) side, (5) shall be open.

Thus, if a ground fault occurs at point A, a ground fault current flows only in # 0, and if a ground fault occurs at point B, ground faults above the threshold value occur in # 0 and # 1-1. If a current flows and a ground fault occurs at point C, a ground fault current above the threshold value flows in # 0, # 1-1 and # 1-2, and similarly, at point D # 0,
# 1-1, # 1-6, # 0, # 1-1, # 1-6, # 2 at point E
-1, at points F, # 0, # 1-1, # 1-6, # 2-1 and # 2
-2, at point G # 0, # 1-1, # 1-6, # 2-1, # 2-6
The ground fault currents above the threshold value respectively flow into the.

Note that in FIG. 2, point C (# 1-
2) Even in an accident, the distribution lines are collectively shown as in # 1-2 to # 1-5, but in reality, the accident current of the distribution line in which the accident occurred is stored as described above.

Therefore, if a ground fault current greater than the threshold value is detected on the trunk lines # 0, # 1-1, # 1-6, for example, it can be known that a ground fault accident has occurred at the point D. These are detection means # 0 and # 1-1 to # 1-6, # 1-1 to # 2-6.
Second detected and measured by ZCT (18) and measuring unit (20b)
The ground fault current distribution pattern shown in Fig. 2 is obtained by specifying the line through which the current above the threshold value flows from the ground fault current value stored in the memory (21b). Can be detected, and the accident section can be detected.

Similarly, the short-circuit fault point can be detected from the short-circuit current distribution pattern, and the fault section can be detected.

In this way, in the master station, the fault section is detected from the created current distribution pattern, and the switches of the healthy section excluding the detected fault section are sequentially turned on remotely by the master station from the upper level to the healthy section. Power transmission of
The faulty section is separated, and the protective relay function is realized without using a protective relay that requires coordinated operation coordination as in the past.

As described above, according to the above-described embodiment, the short-circuit current distribution pattern created based on the short-circuit current value and the ground-fault current value stored in the nonvolatile first and second memories (21a) and (21b), Since the short-circuit fault point and the ground fault fault point can be detected from the fault current distribution pattern, it is possible to detect and disconnect the fault section without using a protective relay that requires coordinated operation coordination as in the past. It becomes possible, and it is possible to easily cope with system changes.

In addition, the ZPD, which is conventionally required, can be deleted, and the configuration can be simplified.

Further, since the fault current value itself can be grasped, the degree of deterioration of the cable can be easily known, which is very advantageous in terms of maintenance.

In addition, in the said Example, although the case of 2 connection system of a multi-circuit switch was demonstrated, even if it is 3 connection systems or more, this invention can be implemented similarly.

〔The invention's effect〕

Since the present invention is configured as described above, it has the effects described below.

When a short circuit or ground fault occurs, only the short circuit current value and the ground fault current value that exceed the threshold value are detected in both nonvolatile memories of each slave station.
Memorize them and collect them in the master station by polling etc. to pattern the fault current distribution, identify the fault section from the short circuit current distribution pattern and the ground fault current distribution pattern created based on this patterning, and identify the short circuit fault point, Since it is possible to detect the ground fault accident point, it is possible to detect and disconnect the fault section only by detecting the current without using a conventional protective relay that requires coordinated operation coordination.
The system can be easily changed.

[Brief description of drawings]

1 and 2 show one embodiment of a protective relay method for a remote multi-circuit switch measurement control device according to the present invention. FIG. 1 is a schematic configuration diagram and FIG. 2 is a ground fault current for explaining operation. Distribution pattern diagram,
FIG. 3 is a schematic configuration diagram of a conventional example. (11b), (20b) …… Measuring section, (12) …… Main line, (13
a), (13b) …… Main line switch, (14) …… Branch line, (1
5) …… Branch switch, (17) …… CT, (18) …… ZCT,
(21a), (21b) ... first and second memories that are first and second non-volatile memories, (22) ... communication line, (# 1),
(# 2) …… Slave station.

Claims (1)

[Claims] 1. A main line switch provided on a main line connected to a distribution line, a branch line switch provided on each of a plurality of branch lines branched from the main line and connected to each consumer, and the main line And detecting means for detecting a ground fault current and a short-circuit current, which are respectively provided on the respective branch lines, for each of a plurality of slave stations, and detect ground faults and short-circuit accidents based on the ground fault and the short-circuit current by the respective detecting means. At times, in the protective relay method of the remote multi-circuit switch measurement control device in which the switch in the accident section is held open and the switch in the sound section is remotely turned on by the master station, a threshold value is set for each slave station. A measuring unit that detects the short-circuit current and the ground fault current that have exceeded, a first non-volatile memory that stores the short-circuit current value, and a second non-volatile memory that stores the ground fault current value are provided, and each of the slave stations At the time of detection, only the current value of ground fault and short circuit accident is detected. The master station remotely stores the main switch to perform trial power transmission, transmits the stored current values of both memories to the master station, creates a fault current distribution pattern, and creates the fault current distribution. Detecting an accident section from a pattern, remotely switching on a switch in a healthy section other than the detected accident section by the master station, and disconnecting the accident section. Electric method.