JPS62185515A - Loop system protective relay system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a loop system maintenance and circulation relay system that takes measures against breaker inoperation.

LA4 invented by B1! In a loop system protection relay system, the present invention provides a backup protection function in the central processing unit that is shorter than the time limit of the backup relay, and trips the breaker adjacent to the inoperable breaker when an accident is detected. This makes it possible to limit the scope of the accident to a narrow range in the event that the trip circuit of the breaker or slave station device is out of order.

C0 Conventional technology Fig. 4 is a configuration explanatory diagram showing a centralized loop system protection relay system. are connected by power transmission lines 32A to 32E. Power transmission lines 32 A and 32
K is connected to the bus bar 33 on the side of the power substation T to form a loop-shaped power transmission system. In the figure, CB and ~CB8 are circuit breakers, and these circuit breakers OB and ~OB are busbars 31A~
31'D and the power transmission lines 32A to 32K. OBA and OBB are circuit breakers inserted in the electric circuit connecting the power transmission lines 32A and 32113 and the bus bar 33 on the power substation T side, and when these circuit breakers CBA and OBB are opened, the loop system is completely stopped. OT, ~OT, in the variable fNI transformer, each pair of current transformers CT, , CT, and OT, , C
T4 sequence c'r, , c'r, and CT, , OT
.

The current information obtained from the 1st to 4th terminals connected in a loop
It is input to terminal devices 34A to 34D. 35 is a central processing unit, and this central processing unit 35 is the first. The fourth terminal device R'(/l A, 34 D Ic is connected, and the current information of each terminal device 1i34A to 34D is supplied to the central processing unit 35f, where it is subjected to protection calculation processing. OTA
, OTB is a current transformer that inputs current information to the central processing unit 35I.

Nao, A-RY, and B-RY are backup relays.

The central processing unit 35 is apparently equivalent to a current differential relay disposed between each current transformer.

FIG. 5 shows the arrangement of this current differential relay.

In FIG. 5, 11 to 19 are current differential relays,
Other parts are shown with the same reference numerals as in FIG.

D0 Problems to be solved by the invention In the apparatus configured as shown in FIG. 4 above, (1)
Assume that an accident occurs on power transmission line 32B between OTz and 075. In this case, even if the current information from CT, OT, is being transmitted correctly, the trip circuit of the slave station device 34B associated with 0B31 may be abnormal, or the OB may be malfunctioning and may be inoperable. Then, the current differential relay 13 operates and OB is tripped.

However, since the CB3 side is abnormal, the accident cannot be eliminated. As a result, there is a problem in that the backup relay B=RY operates and cuts off OBB, resulting in a power outage in the section from power transmission lines 32B to 32K.

(II) Suppose that an accident occurs between OT, , OTI, and (7) (for example, busbar 31c).

At this time, usually C! B, , C! B, , CB8.
OB is tripped. Here, CB4 and OBγ are tripped between OT and OB, OB, and CT.
This is because there are cases where accidents occur between 6 and 6. However, at this time, if the trip circuit of the slave station device 34B related to OB is abnormal or if the fault cannot be removed because CB4 is inoperable, the backup relay A-RY operates to cut off the ODA, and the power transmission line 32 There is a problem that the section from A to 32D is cut off due to power outage. Furthermore, if the trip circuit related to CB is abnormal or OB becomes inoperable, backup relay B-RY operates and OB
There is a problem in that the area between 320K and 32K of the power transmission line will be cut off.

Furthermore, even if an accident occurs on busbar 31C, OB, , C
If B, operates normally, CB7. OB's unresponsive behavior is not a problem. However, in an accident between CB and ~CT, C
B4's unresponsive action becomes a foreshadowing, and in an accident between OB and OT, CB's unresponsive action becomes a problem.

The present invention was made in view of the above-mentioned problems, and when a breaker malfunctions or a failure occurs in the trip circuit,
The purpose of this invention is to provide a loop system protection relay system that can limit the spread of an accident to a minimum.

Measures to solve the E0 bright spot In the central processing unit (here, a backup protection function is provided that is shorter than the time limit of the backup relay at the sending end, and when an accident is detected, it refers to the status information of the customer's breaker. The circuit breaker is characterized in that it outputs a trip signal to the adjacent breaker '4 of the inoperable breaker to cause it to trip.

21 Action For example, if an accident occurs between OT and OB in Figure 4, O
If B is inoperative, conventionally backup relay CBI3 would operate and send '4 nt 320~3.
2E will have a power outage, but in this invention, CAB,
#This adjacent OB is tripped and the accident is removed.

Therefore, the idle section is only the section between the power transmission line 320 and the busbar 31B.

G. Actual Example Figure 1 is a block diagram showing an embodiment of a backup relay in the backup protection function newly added to the central processing unit (5) in the present invention. Backup relay A-RY will be installed.

B-RYE consists of two backup relays A'-RY and B'-RY corresponding to each other, and each relay has a relay OCR' for short circuit detection and a link DG for ground fault detection.
Accident detection No. 1-SA detects time-up signals of timers τ'BS and ``BG'' and timers ``I''jssE and T'BG, which are activated when these relays OCR' and DGR' are operated.

It is equipped with an OR gate OG that outputs as 8B.

In addition, in FIG. 1, backup relay A'-RY
Components within B'-RY are designated by symbol (A), and components within B'-RY are designated by symbol (B).

By the way, backup relay A- at the transmission end of substation T
RY and B-RY are also configured similarly to the configuration shown in FIG. Figure 2 (shows the exact configuration. Figure 2 shows the OC
R, DGR, TB8+TBG all have the same functions as those shown in FIG.

Here, the timer Tmo in the present invention. , T・B,)l time period is set shorter than the timers TBs and TBG in Fig. 2, and luckily TBEI (A) >T'BS(
A), TBS(B) > TBS(B)%TBs(A
)〉T'BG(A), TBG(B) >T'BG
The relationship shown in (B) is set. Also, relay 0 (:!
R, (!IOR' and DGR.

When I get stuck with DGR'ζ, I set the same sensitivity. Therefore, when a breaker malfunctions, an accident detection signal is first output from the back-up I/-A'-RY or B'-RY in FIG.

FIG. 3 is a block diagram showing an embodiment of a trip command circuit for tripping a breaker adjacent to a refractory breaker, and this trip command circuit and backup relays A'-RY and B'-RY of FIG. This constitutes a back-up function within the central processing unit.

In FIG. 3, 11 to 19 are current differential relays shown in FIG. 5, and the outputs of these relays are input to the trip sequence circuit TSQ. The operating status of the current differential relays 11 to 19 (according to this, the output terminals a - j
outputs a "H" level signal.

The output signal of this circuit TSQ is the backup link -A'-
C depending on the combination with the output signals of RY and B'-RY.
B.

~CB, and C! This is input to a logic circuit LGOj which determines whether to trip the BA and CBB circuits. Logic circuit LGO is composed of at gates 20-27 and OR gates 40-47.

Next, the operation will be explained using a specific example.

For example, did a short circuit occur in the section of transmission line 32C?
If OB is defective and the accident is not removed, 0CR (A) and QC! Detected at R'(A). As a result, timer TBS(A) and T'B 8
((trans) is activated at the same time. This activation state is O
If B is defective, the accident will not be removed and the operation will continue as is.

Here, since the time limit of TQ5(A) is short, an accident detection signal is outputted from backup relay A'-RY first. At this time, since the 'DC differential (No. 15) is operating, the trip sequence circuit TSQ outputs a 'H' level signal from the positive and negative terminals θ and f, as is clear from Table 1. This H” level signal is an AND gate%.

24 and OR gate 43.44t are input, but Anne 7
Since the output signal of the backup relay B'-RY is input to the AND gate 24, in the case of this accident example, the conditions of only the AND gate 23 are satisfied, and the output signal is sent to the trip signal of CB3 via the OR gate 42. is output as By ensuring sufficient timed coordination between TBs (A) and T;
There is no need to trip. Therefore, the power outage section can be limited to only two sections: the power transmission line 320 and the bus #31B. The same applies to cases where the accident is not removed due to non-operation of CD4 when there is an accident between 0Tl1%OB5 and non-operation of CD4 and CDl1 when there is an accident between CiT and ~OB. The operation causes a trip output signal to be sent to the OBs. As a result, accidents are eliminated by OB.

The above explanation is an example of the accident continuing on the OBA side, but C
Similarly, if the accident continues on the BB side, T B 5 (B) > 6
s(i)).

TBG (B) > T By providing sufficient time coordination with 1qG (B), it is possible to eliminate the fault using the adjacent circuit breaker before OBB trips. In this case as well, it is natural that sufficient time-limited coordination between the current differential relays 11 to 19 and A'-Ry and B'-Ry is required.

That is, in addition to the trip signal for the breaker ζ that should normally be tripped, a trip signal for the adjacent breaker is output, and the accident is controlled so that the accident propagation section is limited to the adjacent section.

This operation is carried out in the same way no matter which section an accident occurs.Thus, the spread of the accident in the section is kept to a minimum.

Furthermore, since the backup system has two vehicles, the reliability of the system is also improved.

H. As explained in detail about the invention (this invention number), a backup protection function is provided in the central processing unit (which is shorter than the time limit of the backup relay), and when an accident is detected, the breaker becomes inoperable and becomes G. Since the adjacent breaker was cut off, the breaker or slave station device's IJ pump circuit was damaged.
In addition to being able to limit the scope of the accident to a narrow range, it also has the effect of improving the roughness of the system.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a backup relay that is a component of the backup protection function of the present invention, FIG. 2 is a block diagram showing the configuration of a general backup relay, and FIG. 3 is a block diagram showing the configuration of a general backup relay. A block diagram showing an example of a trip command circuit that is a component of the protection function, FIG. 4 is a circuit diagram showing the configuration of a conventional protection electrical system, and FIG. 5 is an equalization circuit diagram of FIG. 4. . OB, ~CB OBA, OBB...breaker, 31
A to 3] D... bus bar, 32 A to 32 E... power transmission line, A-RY, B-RY. A'-RY, B'-RY backup relay, 11
~19・'Wave differential relay, TSQ trip sequence circuit, LGC logic circuit.

Claims (1)

[Scope of Claims] A plurality of slave station devices each having a function of collecting and transmitting current information of a consumer in a loop system, and a function of receiving a transfer trip signal and tripping a disconnector of a consumer; A function to receive information sent from these slave station devices, a function to collect substation current and voltage information, and a function to perform protection processing from both information, a function to trip the substation's circuit breakers, and each slave station device. Loop system protection includes a central processing unit with the function of transmitting transfer trip signals to customers and backup relays installed at substations, and centrally protects the lines and buses in each section of the line leading to customers. In the relay system, a back-up protection function that is shorter than the time limit of the backup relay is provided in the central processing unit, and when an accident is detected, the system refers to status information of the customer's disconnector and removes the unresponsive disconnector. A loop system protection relay system characterized by outputting a trip signal to an adjacent disconnector and tripping it.