JPH0221518A - Interlock circuit of switching device - Google Patents

Abstract

PURPOSE:To prevent a movement to a serious accident by preventing the turning on and off of a switching device when an error operation of an input base including a tail-safe member occurs. CONSTITUTION:When photocouplers responding to auxiliary relays CLX and FSX make an error operation, an instruction output is not issued because it is confirmed to be an error operation of a photo-coupler from the result of operation. Since the CLX and FSX operate, however, their inputs are detected through an input base 1 and an auxiliary relay IIX operates. Since a contact b is opened by operating the auxiliary relay IIX, the turning on and off instruction to a breaker 2 is locked at that time. Consequently, even when troubles are generated at two positions at a time, the circuit to prevent to go to a serious accident can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an interlock circuit for a switchgear with improved reliability.

(Prior Art) In FIG. 5, reference numeral 1 denotes an output board for a photocoupler output that outputs a switching signal to a switching device, for example, a disconnector. Here, CLX and OPX have their respective output caps ON.
It is an auxiliary RY that is excited by this and controls the disconnector. Now, the judgment calculation for the operation of the disconnector is performed on software processing to determine the final input/off output result, and when the disconnector is to be controlled in a large scale, the corresponding photocoupler is turned on to excite CLX.
When performing one-way off control, the corresponding photocoupler is turned on to excite OPX. When CLX or OPX is excited, the corresponding photocoupler is also turned on in order to excite FSX as a fail-safe auxiliary RY. That is, in FIG. 6, the disconnector 2 is not turned on or off only by the operation of CLX or OPX, and the fail-safe auxiliary RYF
The SX contact is also closed, which controls the on/off of the disconnector, improving reliability when interlocks are set up in software processing.

(Problem to be Solved by the Invention) As mentioned above, by providing a fail-safe circuit, an interlock is set up through software processing, but in the unlikely event that the input/output photocoupler of the output board 1 and the error-safe foot of the output board 1 In a situation (malfunction) in which the photocoupler for bright output and the photocoupler for fail-safe are turned ONt when they should not be ONL due to a board failure of the interlock, serious accidents such as personal injury may occur due to the interlock being broken. It is thought that it may cause.

Therefore, an object of the present invention is to provide a circuit that does not cause a serious accident even when two failures occur simultaneously on an output board.

(Structure of the Invention) (Means for Solving the Problems) As shown in Figure 1, when there is a malfunction of the photocoupler on the output board, the calculation result is not output in the judgment calculation. CL under the condition that this calculation result is not output.
By detecting that X, OPX or FSX is working and turning on the output auxiliary RY, the important operation of the disconnector is hindered.

(Function) In Figure 2, CLX and OPX are input to the input board without turning on/off the disconnector according to the calculation results.

When any of the FSXs is activated, the auxiliary RY IIX is energized and the output to the disconnector is locked at the b contact of 11X in FIG.

(Example) In Figures 1 and 2, 11X, CLX, OPX, F
SX is an auxiliary RY that is excited when the corresponding photocoupler on the output board 1 is turned on. C.L.X.

The OPX is excited by outputting a photocoupler corresponding to an on command and an off command, respectively, based on the final judgment of the result of making a decision to control the on/off of the disconnector, including interlock, based on the calculation result. FSX has a fail-safe meaning as mentioned above, and is an auxiliary RY that is excited by outputting it to the corresponding photocoupler when there is a command output from either CLX or OPX. CLX, OPX even though it is not controlled
.

When one of the FSXs operates, the auxiliary RY is excited by detecting this and outputting the corresponding photocoupler.

Now, let us consider a case where a photocoupler corresponding to CLX or FSX malfunctions. The calculation results indicate that the photocoupler is malfunctioning, so no command is output. However, CL
Since the auxiliary RY of X and FSX operates, this input is detected through the input board and causes 11X to operate. In FIG. 3, the b contact opens due to the operation of 11X, so the on/off command to the disconnector 2 is locked at this point. FIG. 4 shows this time chart. For example, the scanning time of the CPU used @10m5
ec, if both CLX and FSX malfunction, the maximum time to detect the return contact input of CLX and FSX is approximately 101113eC, which means that judging from the calculation result, it will take approximately iomsec 10 seconds to excite 11X. Auxiliary RY operating time approx. 20m5eC":) Mari, approx. 30m5e
11
The total time from when the output lock signal is output to when the b contact of the auxiliary RY 11X opens is considered to be 40 m5ec. If the disconnector requires an on/off signal for several seconds to about 10 seconds, the command can only be about 40m5eC, which does not lead to the on/off operation of the disconnector.

〔Effect of the invention〕

As described above, according to the present invention, even if the output board malfunctions including the fail-safe function, it is possible to prevent the switching device from turning on and off, thereby preventing a serious accident in which the ink-lock is broken. You can fully enhance your sexuality.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a logic diagram of the present invention;
Fig. 2 is a block diagram of the output board and auxiliary RY of the present invention, Fig. 3 is a block diagram showing the contacts of the auxiliary RY of the present invention and the on/off operation section of the disconnector, and Fig. 4 is a block diagram of the disconnector of the present invention. FIG. 5 is a diagram of the conventional output board and auxiliary RY, and FIG. 6 is a diagram of the conventional RY's contacts and input board. 1... Output board 2... Disconnector OPX. C.L.X. FSX...Auxiliary relay 3...Malfunction determination section 4゜5...Lock section

Claims (1)

[Claims] It is a device that performs arithmetic processing and outputs open/close signals to the switchgear of the power system, and the open/close signal from the auxiliary relay that operates with the open/close command as a result of the arithmetic processing is replaced by the signal from the auxiliary relay that operates with the fail-safe command. a first lock section that outputs an output at a certain time; a malfunction determination section that determines a malfunction when the output signal of the auxiliary relay is generated without an opening/closing command as a result of the arithmetic processing; and a malfunction determination section that determines that the malfunction has occurred. an interlock circuit for a switchgear, comprising: a second lock section that blocks an opening/closing signal via the first lock section when the opening/closing device is opened/closed;