JPH03127416A - Operation times monitor of circuit breaker - Google Patents

Abstract

PURPOSE:To estimate failure in a circuit breaker by simultaneously monitoring the circuit-breaking operation of the circuit breaker, with the conditions of circuit current and of protective relay, and by integrating the number of operation of the circuit breaker divided into plural kinds based on the relationship. CONSTITUTION:The number of operation of a circuit braker 1 is divided into three cases, so as to be integrated. 1) Current electrified in a steady-state current is integrated by a CPU 6 through a current transformer 4. After the closing of the route of the circuit breaker 1 is operated, the current in the circuit is read after a certain period of time passage by, and the result is integrated by the CPU 6 as the number of closing operation of the route. The number of opening/closing operations in these two cases is defined as the number of electric operation. 2) After a short-circuit accident, opening/closing operation following the operation of an overcurrent relay 3 is integrated by the CPU 6, and the result is defined as the number of accidental breaking operation. 3) Of the cases other than the two cases mentioned above, the number of operation of circuit breaker 1 is defined as the number of mechanical operation. The three kinds of operation number are integrated, and when it exceeds a predetermined value, an alarm is given by the CPU 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a device for monitoring the number of operation times of a circuit breaker used in power receiving and transforming equipment.

(Prior Art) In conventional circuit breaker operation frequency monitoring, when the circuit breaker is turned on and off, it is accumulated as the number of operation times.

Therefore, the state in which the circuit breaker was turned on or off was not monitored.

In other words, regardless of whether the circuit breaker operates by accident, interrupts the rated current and then turns on, or operates while no current is flowing, all operations are treated as the same number of operations and are totaled. Ta.

<Problem to be solved by the invention> When the number of times the circuit breaker is operated is monitored using the above conventional method,
Both harsh operations and light-load operations for the circuit breaker are totaled as the same number of operations, so it is not possible to judge the effect of the obtained number of breaker operations on the circuit breaker, so data is used for preventive maintenance. There was a problem that the use of

An object of the present invention is to provide an operation frequency monitoring device for solving the above-mentioned problems.

[Structure of the invention]

(Means for Solving the Problems) The present invention is a circuit breaker that monitors the circuit breaker operation simultaneously with the circuit current and the state of the protective relay, and divides the number of circuit breaker operations into a plurality of types based on the relationship. This is an operation frequency monitoring device.

(Function) In the present invention, the number of times the breaker is operated is multiplied by dividing it into a plurality of severe cases and severe cases.

(Example) Next, an example of the present invention will be described. Figures 1 and 2 A current transformer 2 is connected in series with the circuit breaker 1 to measure the current value, and a current transformer 2 is connected to the secondary side of the current transformer 2 to measure the current value at a predetermined set value or time. An overcurrent relay 3 that outputs a signal when the current exceeds the current value, a current converter 4 that is connected to the secondary side of the current transformer 2 and converts the current value, and a breaker closing operation that detects the closing operation of the circuit breaker l. A detection circuit 20a, a circuit breaker opening operation detection circuit 20b that detects the opening operation of the circuit breaker 1, an energizing current determination function 21 that is connected to the circuit breaker closing operation detection circuit 20a and that determines the presence or absence of energizing current, and a circuit breaker A pre-operation current determination function 22 that is connected to the opening operation detection circuit 20b and determines whether or not there is an overcurrent before the circuit breaker operates; and a Chosai 11i flow determination function 2.
a relay operation determination function 23 that determines whether or not the overcurrent relay 3 has been activated based on the output of the relay operation determination function 23; This figure shows a circuit breaker operation frequency monitoring device that includes a pre-operation current determination function 22 and an electrical operation frequency counting circuit 25 that counts the number of electrical operations based on the output from the relay operation determination function 23.

That is, on the circuit breaker to be monitored, the current transformer 2 for transforming the current, the overcurrent relay 3 connected to the secondary side of the current transformer 2, and the current transformer 2 A current converter 4 connected to the next side, a process interface 5 that inputs these operating signals and output signals, and a CPU that processes the data.
Consisting of 6. FIG. 2 shows a flowchart of the processing contents of the CPU 6.

In the above configuration, the number of operations is divided into the following three cases and integrated.

(1) The current during steady current flow is converted to C through the current converter 4.
It is read by the PU6 and the CPU6 adds up the information that has been cut off at that time. Further, after the circuit breaker 1 closes the circuit, the current in the circuit is read after a period of time has elapsed, and the CPU 5 integrates it as the number of circuit closing operations. The number of times of these two opening/closing operations is defined as the number of electrical operations.

■ Short introduction After the accident, the CPU 6 integrates the opening operations accompanied by three overcurrent relay operations. This is taken as the number of accidental shutoff operations.

■ Calculate the number of times circuit breaker 1 operates for reasons other than the above two items.
Integrate with PU6. This is defined as the number of mechanical operations.

As described above, the number of times the circuit breaker I is operated can be accumulated in three cases: the number of electrical operations, the number of accidental breaking operations, and the number of mechanical operations.

〔Effect of the invention〕

The circuit breaker operation frequency monitoring device of the present invention monitors the number of operations by interrupting steady current, electrical operation number when energization occurs after circuit closing, number of accidental tripping when overcurrent is interrupted, and other items other than these two items. By setting the number of operations as the number of mechanical operations,
It is now possible to accumulate data that takes into consideration the conditions under which the circuit breaker has operated, and this integrated value can be set to a predefined value, and if this set value is exceeded, an alarm will be generated from the CPU. This makes it possible to predict circuit breaker failures.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a monitoring device showing an embodiment of the present invention, and FIG. 2 is a flowchart explanatory diagram of the present invention. 20a... Breaker closing operation detection circuit 20b... Breaker opening operation detection circuit 21... Energizing current judgment function 22... Pre-operation current judgment function 23... Relay operation judgment function 24... Accident Interruption operation number counting circuit 25...Electrical operation number counting circuit

Claims (1)

[Claims] A current transformer that is connected in series with the circuit breaker to measure the current value;
an overcurrent relay connected to the secondary side of the current transformer; a current converter connected to the secondary side of the current transformer to convert a current value; and a circuit breaker to detect closing operation of the circuit breaker. a closing operation detection circuit, a circuit breaker opening operation circuit that detects the opening operation of the circuit breaker, and an energizing current determination function that receives the output of the circuit breaker closing operation detection circuit and determines the presence or absence of energizing current after the circuit breaker closes. a pre-operation current determination function that receives the output of the circuit breaker opening operation detection circuit and determines whether or not there is energization before the circuit breaker opens; and if the pre-operation current determination function determines that there is energization, the overcurrent a relay operation determination function that determines whether or not the relay has operated; an accidental interruption operation count circuit that operates when the relay operation determination function determines that the relay has operated; and the energizing current determination function and the before operation. A circuit breaker comprising an electrical operation number counting circuit that counts the number of electrical operations when the current determination function determines that energization is present and when the relay operation determination function determines that the relay does not operate. Operation frequency monitoring device.