JPH02106118A - Switchgear - Google Patents

Abstract

PURPOSE:To diagnose the abnormality of a control circuit and a switching mechanism respectively by comparing the time to be elapsed before start of operation on and after reception of a switching command and the time to be elapsed before completion of operation on and after start of operation with normal times and managing the times. CONSTITUTION:A photo-optical switch is fixed to a circuitbreaker mechanism, and a time T1 to be elapsed before start of operation of the circuitbreaker on and after reception of a throw-in and trip signals from time measuring circuits 20, 21 which receive output from the photo-optical switch and a time T2 to be elapsed after start of operation of the circuitbreaker before completion of operation thereof are measured. Then the times T1, T2 are compared with normal times in a CPU 22 according to a time comparison program 23. If the time T1 is longer than the normal time, it is judged that the friction of grease has increased and that mainly the control circuit is abnormal. If the time T2 is longer than the normal time, it is judged that the mechanism does not function smoothly because of deformation or abrasion of the rotary section of the mechanism and that mainly the switching mechanism is abnormal. If both times T1, T2 are longer than the normal times, it is judged that aforementioned phenomena are combined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a switch having a control circuit and a switching mechanism, such as a circuit breaker used in a power system, for example.

(Prior Art) Conventionally, in order to determine whether the operation of this type of switch is normal or not, a method has been used to measure the opening/closing time and determine whether it is normal or abnormal. That is, the opening/closing mechanism is diagnosed by receiving an opening/closing command from outside the switch, measuring the time T from the time the opening/closing command is received until the operation is completed, and comparing it with a normal value.

Hereinafter, such a switch with a diagnostic function will be explained using a circuit breaker as an example, with reference to a sequence diagram showing a control circuit of a circuit breaker in FIG. In other words, the outline of the closing operation is as follows.
In FIG. 5(a), when the contact 100 of the closing command circuit is closed, the auxiliary closing relay 52X operates, energizes the closing coil 52C, and closes the contact portion of the switch 52 in FIG. 5(b). At the same time, this closed circuit state is maintained mechanically.

Due to the above-described closing operation, the closing auxiliary relay 52X is deenergized, so that the closing coil 52C is deenergized. In the above case, since the resistor 102 is connected in series to the closing coil 52C, while the closing coil 52C is energized, that is,
A voltage will appear across the resistor 102 from when the closing command is issued until the closing operation is completed.

On the other hand, as a summary of the tripping operation, when the contact 101 of the tripping command circuit is closed, the tripping coil 52T is energized to remove the holding mechanism of the circuit breaker, and the tripping operation is instantaneously performed. When the tripping operation is completed, the tripping coil 52T is deenergized to prevent the tripping coil 52T from overheating. In the above case, since the resistor 103 is connected in series to the tripping coil 52T, the tripping coil 52T is energized, that is, from the time the tripping command is received until the tripping operation is completed. During this time, a voltage will appear across the resistor 103.

As seen above in the overview of the closing and tripping operations, the resistance 1
By setting n1 the time during which the voltage appears on both ends of 02.103, the time T from receiving the opening/closing command until the operation is completed can be measured.

(Problem to be solved by the invention) As a result of measuring the time T from receiving the opening/closing command to completing the operation as described above and comparing it with the normal value, it is found that the measured value exceeds the normal order. For example, it can be determined that the opening/closing mechanism is abnormal, but it is difficult to determine whether this abnormality is due to an increase in frictional force in the opening/closing mechanism, an abnormality in the closing coil or tripping coil of the control circuit, or a stubbornness in the opening/closing mechanism. I can't figure out the cause. Therefore, it was difficult for the customer to grasp the point of maintenance and inspection work before the switch became inoperable, and the switch could not be closed or tripped, which could lead to an accident.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a switch having a function of diagnosing abnormalities in a control circuit and a switching mechanism.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a time T1 from receiving an opening/closing command to the opening/closing mechanism to the start of the operation, and a time T1 from the start of the operation to the completion of the operation. The time T2 is compared and managed with the respective normal values.

(Function) According to the above, if T1 becomes larger than the normal value, there may be an increase in the frictional force of grease, etc., or a change in the excitation characteristics of the closing coil or trip coil, and it is likely that there is an abnormality in the control circuit. In addition, if T2 becomes larger than the normal value, deterioration of the spring, deformation of the rotating part of the mechanism, or stiffness of the mechanism due to friction can be considered, and it can be determined that the opening/closing mechanism is abnormal. , T2 become large, the above-mentioned compound phenomenon can be considered.

Therefore, if T1 and T2 are managed separately, the cause of the abnormality can be estimated and diagnosed, and maintenance and inspection can be performed to prevent inoperability.

(Embodiment) An embodiment of the switch according to the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a front view of the circuit breaker mechanism, and FIG. 2 is a sectional view taken along line AA in FIG. As shown in FIGS. 1 and 2, the circuit breaker mechanism 1 includes a mechanism frame 2, a closing spring 3, a tripping spring 4, a closing coil 5, a tripping coil 6, a main shaft 7, a drive lever 8, It is composed of a connecting rod 9 and the like, and a blocking section 10 is connected to the other end of the connecting rod 9, and a contact (not shown) in the blocking section 10 is closed and tripped.

To explain in detail, when an opening/closing command, for example a closing command, is input, the closing coil 5 is energized, and the closing spring 3 that has been pulled is locked or released.
is contracted, the main shaft 7 rotates to the left, the drive lever 8 also rotates to the left, the connecting rod 9 moves to the right, and the contact in the interrupting part 10 is closed. FIG. 2 shows the charging state.

Similarly, when a tripping command is input, the tripping coil 6 is energized, and the tripping spring 4, which is in the tensioned state in FIG. As the drive lever 8 rotates, the drive lever 8 rotates to the right, the connecting rod 9 moves to the left, and the contacts in the interrupting part 10 are opened. That is, when the drive lever 8 is at the "I" position in FIG. 2, it is in the closed state, and when it is at the "■" position, it is in the open state.

In the above mechanism, a photoelectric switch 11 and a disk 14 having a small hole 12° 13 in the main shaft 7 are attached to the mechanism frame 2. In this case, photoelectric switch 1
1 uses a reflective type.

Here, in the closed state, that is, the state shown in FIG. 2, the light emitted from the charging switch 11 passes through the small hole 12, so there is no output from the photoelectric switch 11. next,
When the circuit breaker mechanism 1 starts the opening operation, the main shaft 7
begins to rotate in the right direction, and the light that has passed through the small hole 12 of the disc 14 is reflected and returns to the photoelectric switch 11, where it outputs an output. When the opening operation is completed, the light from the photoelectric switch 11 passes through the small hole 13 of the disk 14 attached to the main shaft, and the output of the photoelectric switch 11 disappears. The operation from the open state to the closed state is the reverse of the above.

As described above, the operation start point and operation completion point of the circuit breaker mechanism 1 can be determined as shown in the time chart of FIG. Here, FIG. 4 shows an example of a block diagram of a time measuring circuit for measuring the operation start time TI from receiving the command and the time T2 from the operation start to the operation completion. In FIG. 4, the light from the light emitting diode 24 passes through and is reflected by the disk 14, turning the transistor 15 ON and OFF, and its output is amplified and sent to the comparators 17 and 18.

In this case, the photoelectric switch 11 is formed by the light emitting diode 24 and the transistor 15.

A command signal that enters the coil (trip, close) 25 is captured by a current transformer 16, passed through a filter 19, and sent to comparators 17 and 18. The comparator 17 outputs an output signal when the current and voltage values exceed a certain threshold value, and the comparator 18 outputs an output signal when the current and voltage values fall below a certain threshold value. The output signals of the comparators 17 and 18 cause the T measurement counter 20 and the T2 measurement counter 21 to be started and reset. The counters 20 and 21 are connected to a CPU 22 and include a time comparison program 23.

As described above, according to this embodiment, the photoelectric switch 11 is attached to the circuit breaker mechanism, and the output of this photoelectric switch 11 is introduced into the time meter α1 circuit, so that the circuit breaker operates after the closing and tripping signals are input. The time T until the circuit breaker starts operating and the time T2 from when the circuit breaker starts operating until it completes can be measured and compared with normal values by the time comparison program 23 in the CPU 22.

According to the above, if T becomes larger compared to the normal value,
Possible causes include an increase in frictional force due to grease, etc., and changes in the excitation characteristics of the closing coil and trip coil, and it can be determined that the control circuit is mainly abnormal. Furthermore, if T2 becomes larger than the normal value, it is possible that the mechanism is stiff due to deterioration of the spring, deformation of the rotating part of the mechanism, or wear, and it can be determined that the opening/closing mechanism is mainly abnormal.

Furthermore, if both T1 and T2 become large, the above-mentioned compound phenomenon can be considered. Therefore, if T1 and T2 are managed separately, the cause of the abnormality can be estimated and diagnosed, and maintenance and inspection can be performed to prevent inoperability.

[Effect of explanation] As described above, according to the present invention, the opening/closing time is managed divided into T and T2, and each is compared and managed with the normal value, so that abnormalities in the opening/closing mechanism and abnormalities in the control circuit can be avoided. We can provide a switch that can diagnose both.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the switch according to the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, FIG. 3 is a time chart of circuit breaker operation in the same embodiment, and FIG. 4 is a time measurement block diagram of the same embodiment, and FIG. 5 is a sequence diagram of the circuit breaker control circuit. 1... Circuit breaker mechanism, 7... Main shaft, 11.
...Photoelectric switch, 12.13...Small hole, 14...
disk. Applicant's agent Patent attorney Takehiko Suzue Figure 5 Opening and almost complete operation @ Source ST 9 (b) Figure 5

Claims (1)

[Claims] In a switch that has a control circuit and an opening/closing mechanism and operates the control circuit and the opening/closing mechanism upon receiving an opening/closing command, the time T_1 from receiving the operation command until the opening/closing mechanism starts operating. and a time T_2 from the start of operation to the completion of the operation of the opening/closing mechanism.
2. A switch characterized in that an abnormality in the control circuit and the switching mechanism is diagnosed based on the above.