JPS59127522A - Inspection starting circuit - 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 [Technical Field of the Invention] The present invention relates to an inspection activation circuit, and particularly to an inspection activation circuit for preventing an inspection activation lock when an apparatus is locked.

[Technical background of the invention]

Protective relay devices that protect power systems generally have constant monitoring and automatic inspection functions in order to quickly discover abnormalities in the device in addition to their original purpose of protection, and they also have automatic monitoring of the device itself. We are trying to improve reliability by doing this. Here, we will explain the inspection activation of the inspection circuit related to trip circuit monitoring of the circuit breaker.

FIG. 1 shows a circuit for detecting disconnection of a trip circuit of a circuit breaker. Disconnection monitoring relay KX-1 when the circuit breaker is closed,
KX-2 is a seal-in relay TX.

Current limiting resistor R, trip lock terminal T T-1, T
T-2 and breaker trip coil TC1 breaker auxiliary a
These KX-1, K
X-2 is operating when the trip circuit is normal.

The coil resistances of KX-1 and KX-2 are selected to such values that jC and TX do not operate unnecessarily. 52bX is an amplification relay for the breaker auxiliary contact 52b. The operations of 52a and 52b during breaker operation are as follows.

52a 52b Breaker closed Closed Breaker opened Open Closed M represents the output contact of the protective relay, and 11X is a contact that is normally closed and opens only during inspection.

FIG. 2 is a diagram showing the trigger circuit, the relay to be constantly monitored, and the conditions for starting the inspection, and the circuit is locked from starting the inspection if an unnecessary operation occurs in these. ORI
, OR2 is an OR circuit, N0TI.

NOT 2 is a NOT circuit, AND 1, AND 2
means an AND circuit. Also, Ml, M2, M
3 and M4 represent relay outputs to be constantly monitored, and MX is a relay monitoring signal that monitors the outputs of these relays. 'On the other hand, KX is a trip circuit monitoring signal that monitors trip circuit disconnection of the circuit breaker. These MX and KX O
It is composed of an R circuit. When the constant monitoring signal SV is normal, Ml, M2, M3, and M4 output "0", so that MX shows the "0" level.

■52bX contact [closed J KX-1, KX-2 contact “open”
YoshiKX indicates rOJ level.

Depending on the situation, the level will continue to be “0”. As a result, the SV inversion signal "■" indicates "1", and the inspection start signal ST is "1".
The inspection will be activated depending on the conditions.

[Problems with background technology]

By the way, once a malfunction occurs in a constantly monitored relay or trip circuit, etc., this is detected by the SV, and if the constant monitoring failure occurs on the condition that the inspection is not activated,
Normally, a detailed investigation is conducted to find out which part of which circuit is defective, and appropriate measures are taken.

Here, we will explain the deficiencies of the circuit mentioned above during a detailed investigation when a malfunction occurs in the device. As shown in FIG. 3, recent protection devices usually have a triple protection function consisting of two main protection systems and one backup protection system, each of which has an automatic monitoring function added to it. Therefore, even if a malfunction occurs in one series of protection devices, it is possible to operate the device without stopping the protected device (for example, a power transmission line protection device).

On the other hand, a detailed investigation of the equipment in which the malfunction occurred was carried out by TT as shown in Figure 1.
-1 and TT-2 are normally opened (referred to as trip lock, hereinafter the same). In this case KX-1,
KX-2 returns and 52bX continues to return. Therefore, KX in Figure 2 indicates "1", "■" indicates "0",
Inspection activation by ST will be unnecessarily locked, and the automatic inspection function will not operate. As a result, a defect occurs in which it is not possible to investigate the defective part by automatic inspection activation. In addition,
When the circuit breaker opens, 52bX changes from closed to open, so even if KX-1 and KX-2 are closed, KX remains "0" and Bean remains "1", and the inspection start is not locked. . As described above, the inability to diagnose malfunctions in the protection device using the automatic inspection activation lock reduces the automatic inspection function by half, which greatly impedes detailed investigation to find malfunctions. In addition, similar problems have also occurred during repairs due to device locks and confirmation tests after periodic inspections. In order to eliminate this problem, conventionally the TT-1 and TT shown in Fig.
A simulated breaker is connected to the top of -2 each time,
This method has the following disadvantages.

■There is a risk of contact burnout due to incorrect connection.

■It is time-consuming to use a simulated breaker for rainfall each time.

■Disconnecting the simulated circuit breaker several times will unnecessarily extend the locking time of the device and lead to a decline in the protection function.

In order to solve these problems, a new technology with a simple configuration and low cost has been awaited.

[Purpose of the invention]

The present invention has been made with the aim of solving the above-mentioned problems, and it is possible to perform various operations by trip-locking the protected equipment without stopping the protected equipment. The purpose of this invention is to provide an inspection starting circuit that can perform its original function by removing the factors that cause the automatic inspection starting port to avoid backfires.

[Summary of the invention]

The present invention prevents an inspection lock signal from being generated when a malfunction occurs in a constantly monitored relay, trip circuit, etc., and the trip lock terminal in the trip circuit is opened to investigate the cause. In order to
Create an AND condition between the open/close state of the circuit breaker, the open/close state of the trip lock terminal, and the output from the terminal that enables the connection to the θ level. When the trip lock terminal is opened, the AND condition is invalidated. This is intended to prevent the generation of the inspection lock signal.

[Embodiments of the invention]

Examples will be described below with reference to the drawings. FIG. 4 is a configuration diagram of an embodiment of the inspection start/cancel circuit according to the present invention. Fourth
The figure shows 52bX, KX-1, KX-2 and N in Figure 2.
This is a diagram in which the present invention is applied to the OT 1 part, and a terminal cp is provided for connection to the OV in the J AND condition AND 3.

This lock terminal is one that can be easily operated by, for example, a check bin.

Next, to explain the operation, 52bX maintains the reset state when the circuit breaker is closed, and KX-1 and KX-2 do not reset when the device port is opened when TT-1 and TT-2 are opened.
'', but by connecting the lock terminal cp to Ov, it is possible to easily control KX from 11'' to 0. Connection to 0■ can be easily made by operating the check pin on the lock terminal. The present invention solves the problem of the inspection activation lock, which caused the opening of TT-1 and TT-2 due to the device lock in the prior art, and makes it possible to easily release the inspection activation lock. As a result, it has become possible to significantly improve the drawbacks described in the prior art. The inspection start lock can be released by connecting the cp shown in Figure 4. A with the trip circuit
Since it is provided to operate under ND conditions, inspection and activation can be performed even if the trip circuit is opened or closed.

FIG. 5 is a block diagram of another embodiment. That is, AND 4 i which acts as an AND condition after taking both conditions of the trip monitoring circuit and the relay monitoring circuit for inspection start lock release.
It may be provided. In this case, even if a continuous monitoring failure occurs, inspection and activation can be performed. The present invention can be applied even if the position where the lock circuit is installed changes as described above.

Further, the contents of the lock terminal are not limited to the above-mentioned example, and may have any structure as long as it can be connected to the OV.

〔Effect of the invention〕

As described above, by applying the present invention, the disadvantage that inspection activation is not possible when a trip is locked due to the inspection activation port provided in the trip monitoring circuit and the release circuit is eliminated, and the lock can be easily released. It is possible to provide a very effective inspection starting circuit that allows a detailed inspection of the device to be carried out using the inspection function provided in the device.

[Brief explanation of drawings]

Fig. 1 is a diagram of an embodiment for detecting disconnection of the Tri-knob circuit of a circuit breaker, Fig. 2 is a diagram of an embodiment for detecting a constant monitoring circuit check activation lock, and Fig. 3 is an example of the configuration of the Hoto device. FIG. 4 is a diagram showing one embodiment of the inspection starting circuit according to the present invention, and FIG. 5 is a diagram showing another embodiment of the present invention. KX-1, KX-2・Disconnection monitoring relay, TX...Seal-in relay, TT-1, TT-2...Trip lock terminal, TC
...Tri-lag coil, 52a, 52b...Auxiliary contact of breaker, 52bX
...Amplification relay, M1-M4...Relay output subject to constant monitoring, MX...
Relay monitoring signal, KX...trip circuit monitoring signal, ST...inspection start signal, CP/port, terminal. (7317) Agent Patent attorney Aide Kensuke (and 1 other person) Figure 3 Tun 4 Figure 5

Claims (1)

[Claims] In the inspection starting circuit that inspects the protective relay by inputting the relay monitoring signal from the relay subject to constant monitoring and the trip circuit monitoring signal from the open/closed state of the breaker and the open/closed state of the trip lock terminal, A trip circuit monitoring signal is formed based on the AND condition of the open/close state and the open/close state of the trip lock terminal and the output from the terminal that enables connection and release with the 0 level, and the inspection lock is activated by opening the trip lock terminal. An inspection starting circuit characterized by blocking.