KR20000075101A - Sensing and counting device incoming over current to electric power machine - Google Patents

Abstract

PURPOSE: An over current inflow sensing and counting apparatus is provided to prevent an obstacle of a power facility by counting, storing and displaying a sensed over current frequency. CONSTITUTION: An over current inflow sensing and counting apparatus comprises sensors(5a-5d) which are connected to sense electric lines(3a-3d) and are connected to an input part(6) so as to supply currents of respective phases sensed by the sense electric lines to the input part(6). A reference setting part(7) sets a reference voltage for judging whether the sensed currents through the input part is abnormal. A comparator(8) compares the sensed current from the input part with the reference value. An output control part(9) judges current supplied from a current power facility(2) as an abnormal state when a high signal is supplied from the comparator(8), to thus output a counting signal. A counter(10) increases a counting coefficient whenever the counting signal is output from the output control part(9), and a display part(11) displays an output of the counter(10).

Description

Sensing and counting device incoming over current to electric power machine}

The present invention relates to an overcurrent inflow detection and counting device of a power device, and more particularly, to counting and storing and displaying the number of interruptions of a circuit breaker that blocks a fault current in the event of an overcurrent supplied to a transformer and an external fault, This is related to the overcurrent inflow detection and counting device of power equipment that prevents the breakdown of power equipment and supplies high-quality power to consumers by using the number of times of overcurrent supply as a preventive inspection and maintenance data of power equipment.

In general, power supplied by a power company is supplied to a consumer through a power device such as a transformer or a breaker.

The transformer is to reduce or boost the power supplied by the power company so that it can be used on the consumer side, and the breaker is to prevent the protection of accidents and the propagation of the health line when a large predetermined current flows due to a failure on the supply line or the consumer side. In order to prevent breakdown accidents and equipment failure of customers by blocking the fault line.

Currently, the preventive maintenance intervals of transformers and circuit breakers are set according to the period of use. Transformers are usually inspected about once every three years and whether there is a problem with the device. have.

If an overcurrent (fault current) is supplied from the outside while the transformer is in operation, the winding insulation strength of the transformer decreases and a mechanical shock occurs depending on the magnitude of the overcurrent, and when this phenomenon accumulates, the transformer may fail.

Therefore, in order to prevent the failure of the transformer in advance, the number of overcurrents supplied to the transformer is counted, and when the number of counts reaches a certain value, the transformer may be checked more effectively if the transformer is inspected and repaired.

In addition, the breaker is inspected and repaired once every 2 or 3 years depending on the type of breaker. However, it is very unreasonable to calculate the check and repair cycle according to the use period of the breaker.

That is, since the breaker is worn and damaged by the current interruption when the overcurrent flows, when the breaker operates 20-30 times the overcurrent interruption, rather than checking and repairing once within a predetermined period as described above. It is known that it is more desirable to perform maintenance checks.

However, conventionally, since no device capable of counting the number of times of overcurrent supplied to the transformer or the number of times of breaker current interruption operation of the circuit breaker was provided, maintenance of the transformer and the circuit breaker could not be performed at an appropriate time. Or breaker breakdown occurs, and the problem of failing to provide high-quality electricity to consumers.

Accordingly, the present invention for solving the above problems is to detect the overcurrent supplied to a power device such as a transformer or a breaker, and to count and store and display the number of detected overcurrent, the number of overcurrent supply to the counted and stored power device It aims to provide overcurrent inflow detection and counting device of power equipment that prevents the breakdown of power equipment by using information as preventive inspection and maintenance data of power equipment and to supply high quality power to consumers.

Features of the present invention for achieving the above object,

In the R, S, T phase current supplied from the power company is supplied to a power device such as a transformer or a breaker through the power line, the first sensing wire connected to the current meter is connected to the power line, respectively,

A second sensing sensor configured to attach a sensor capable of sensing a current of each phase to the first sensing wire to sense currents of R, S, T, and N phases;

An input unit configured to receive and level the current supplied to the power device through the second detection sensor;

A reference value setting unit configured of a plurality of variable resistors whose resistance values are changed according to a user's adjustment, and setting a reference value, which is a reference for determining whether overcurrent is supplied;

A comparison unit comparing the sensed current input through the input unit with the set reference value and outputting a high or low signal according to the difference value;

An output controller which determines that the sense current is an overcurrent when the high signal is output from the comparator, and outputs a predetermined counting signal;

A counter that counts each time a counting signal is input,

And a display unit for displaying the number counted by the counter on a screen.

1 is a block diagram showing an overcurrent inflow detection and counting apparatus of the present invention.

2 is a circuit diagram showing a reference value setting unit applied to the present invention.

3 is a flow chart showing the operation of the present invention.

<Description of the symbols for the main parts of the drawings>

1: power line, 2: power equipment,

3a to 3d: first sensing wire, 4: protective relay,

5a to 5d: second sensing sensor, 6: input unit,

7: reference value setting section, 8: comparison section,

9: output control unit, 10: counter,

11: indicator, 12: battery,

SW: power switch, VR1 to VR4: variable resistor,

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings, FIGS. 1 to 3.

Reference numeral 1 denotes a power line to which electric power is supplied to a power device 2 such as a transformer or a breaker in a power company, and currents of R phase, S phase, and T phase are supplied through the power line 1.

Each of the power lines 1 is connected to the first sensing wires 3a to 3d connected to the current meter 4 so that current supplied to the power device 2 through the power line 1 is supplied to the current meter 4. Or for use in protective relays.

In addition, second sensing sensors 5a to 5d are connected to each of the first sensing wires 3a to 3d, and the second sensing sensors 5a to 5d are connected to the input unit 6 to connect the first sensing wire. The currents of the respective phases R, S, T, and N detected at 3a to 3d are supplied to the input unit 6.

The input unit 6 supplies the comparator 8 to level up and detect the sensing current of each phase input from the second sensing sensors 5a to 5d.

Reference numeral 7 denotes a reference value setting unit for setting a reference value, which is a reference for discriminating whether the sense current input through the input unit 6 is a fault current or a normal current, which is shown in FIG. As shown in the drawing, the first to fourth variable resistors VR1 to VR4 are configured to produce an output compared with the input unit 6.

The resistances of the variable resistors VR1 to VR4 vary according to the user's adjustment, and the user can appropriately adjust the variable resistors VR1 to VR4 to appropriately change the reference value according to the situation.

The reference value to be set can be set within a range of approximately 1A to 10A, and for ground fault, the reference set value can be adjusted within a range of 0.5 to 5A.

Reference numeral 8 denotes a comparison unit. The comparison unit 8 compares the sense current input through the input unit 6 with the reference value set by the reference value setting unit 7 and generates a high or low signal according to the result. It outputs to the output control part 9 which follows.

That is, when it is determined that the sensing current is large as a result of the comparison between the sensing current and the reference value, the high signal is output to the output controller 9, and when the sensing current is small, the low signal is output to the output controller 9.

The output controller 9 determines whether or not the sense current is an overcurrent. When a high signal is input from the comparator 8, it is determined that the current supplied to the power device 2 is an overcurrent. Outputs a counting signal, and when the low signal is input from the comparator 8, it is determined that a normal current is currently supplied to the power device 2, and maintains the state.

A counter 10 and a display unit 11 are installed at the rear end of the output control unit 9, and the counter 10 increases and stores the counting coefficient by '1' whenever a counting signal is output from the output control unit 9. The display unit 11 allows the user to display the number counted by the counter 10 on the screen.

The display unit 11 may be implemented by using a seven segment or a liquid crystal display (LCD).

On the other hand, the above-described components are supplied by the self-power supply by receiving AC power of 220V and the counter power is built in the battery to maintain the stored number of operations even if the power supply is interrupted.

Referring to the operation of the present invention configured as described above is as follows.

First, when the user turns on the power switch SW, the power of the battery 12 is supplied to each component to operate, and the user operates the first to fourth variable resistors constituting the reference value setting unit 7. VR1 to VR4) are adjusted to set a reference value, which is a reference for determining whether the sense current is an overcurrent or not.

Thereafter, when power is supplied to the power device 2 through the power line 1, the first sensing wires 3a to 3d may draw currents of the respective phases R, S, T, and N supplied to the power device 2. Sensing and supplying to the current meter (4), the second sensing sensors (5a to 5d) senses the current supplied to the current meter (4) and supplies it to the input unit (6).

The input unit 6 outputs the sensing current sensed by the second sensing wires 5a to 5d to the comparator 8 by leveling it, and the comparator 8 detects the input from the input unit 6. The current and the reference value set by the reference value setting unit 7 are compared with each other, and as a result of the comparison, a high signal is output when the sensing current is greater than the reference value, and a low signal is output when the sensing current is smaller than the reference value.

When the low signal is output from the comparator 8, the output controller 9 maintains the current state by determining that a current of a normal level is supplied to the current power device 2. When the signal is output, it is determined that an abnormally high current, that is, an overcurrent (fault current) is supplied to the current power device 2, and outputs a predetermined counting signal to the counter 10.

The counter 10 receiving the counting signal output from the output control unit 9 increases its counting coefficient by 1, and the value counted by the counter 10 is numerically displayed through the display unit 11. Is displayed and can be viewed by the user.

When a series of overcurrent sensing operations as described above are repeatedly performed over a period of time, when the user refers to the number counted by the counter 10 to check whether the corresponding power device 2 has failed, the overcurrent may be Since the number of times supplied to the device 2 (transformer or breaker) can be known, the state of the power device 2 can be estimated according to the counted number, thereby preventing the maintenance of a power device such as a transformer or a breaker. .

As described above, the present invention provides a means for detecting a current supplied to a power device such as a transformer or a breaker, means for comparing the detected current with a preset reference current and determining whether the detected current is an overcurrent; As a result of the determination, if the current supplied to the power device is an overcurrent, the counting coefficient is increased by '1' to configure a means for storing and displaying, to detect the overcurrent supplied to the power device, and to count and store the number of detected overcurrents. Therefore, by using the information of the number of over-current supply to the counted and stored power equipment as the preventive inspection and maintenance data of the power equipment, it prevents the failure of the power equipment and detects the overcurrent inflow of the power equipment to supply high-quality power to the consumer. Counting device.

Claims (1)

Currents of R phase, S phase and T phase supplied from the electric power company are supplied to the power device 2 such as a transformer or a circuit breaker through the power line 1, and the power line 1 is connected to a current meter 4. In the one sensing wires 3a to 3d connected to each other, Second sensing sensors 5a to 5d connected to the first sensing wires 3a to 3d to sense currents of R phase, S phase, T phase and N phase supplied to the power device 2, An input unit 6 for receiving and leveling and outputting a current supplied to the power device 2 through the second detection sensors 5a to 5d; A reference value setting unit (7) configured of a plurality of variable resistors (VR1 to VR4) whose resistance values are varied according to a user's adjustment, and setting a reference value which is a reference for determining whether overcurrent is supplied; A comparator 8 which compares the sensed current input through the input unit 6 with the set reference value and outputs a high or low signal according to the difference value; An output controller 9 which determines that the sense current is an overcurrent when the high signal is output from the comparator 8, and outputs a predetermined counting signal; A counter 10 that counts each time a counting signal is input, Overcurrent inflow detection and counting device of the power device, characterized in that consisting of a display unit for displaying the number counted in the counter (10) on the screen.