KR20090114259A - Circuit breaker for using active bypass reclosing and operation method therefor - Google Patents

Abstract

PURPOSE: A circuit breaker and an operation method thereof are provided to reduce repetitive power failure by relieving a shock of a power facility due to a flow of a repetitive accident current. CONSTITUTION: A main reclosing breaker(100) includes an accident current sensing and controlling part(110) and a blocking switch(120). In case an accident current flows from a first system to a second system, the accident current sensing and controlling part applies a blocking signal to a blocking switch and a sub low voltage bypass circuit(200), and receives a reclosing signal and a permanent opening signal from the sub low voltage bypass circuit. The blocking switch turns on the switch according to the reclosing signal of the accident current sensing and controlling part. The blocking switch continuously turns off the switch according to the permanent opening signal of the accident current sensing and controlling part.

Description

CIRCUIT BREAKER FOR USING ACTIVE BYPASS RECLOSING AND OPERATION METHOD THEREFOR}

The present invention relates to a circuit breaker and an operation method using an active bypass reclosing, and more particularly, to mitigate the impact of the power equipment caused by the repeated inflow of the accident current, to reduce the repeated instantaneous power failure, as well as the instantaneous accident and permanent accident It relates to a technique for discriminating.

In general, an automatic recloser detects an accident current in the event of an accident on the track, cuts off the circuit by the time current characteristics (TCC), and restarts the circuit after a certain time. This equipment is to close or reclose the circuit according to the magnitude of the fault current flowing into the fault circuit by reclose.

The above-mentioned equipment is continuously repeated according to a predetermined operation sequence to resume supply of power in case of a momentary accident, and in case of a permanent accident, the breaker is locked out to separate an accident part from the power system. Depending on the power company, the operation sequence of 2F2D or 1F2D is followed, where F is fast operation in the time-current characteristic curve, and D is delayed operation.

These automatic reclosing breakers are applied to a variety of transmission and distribution power system, and there are automatic reclosing breakers made by combining the two functions. In the event of an accident, the reliability of the power supply to the power system can be increased.

Recently, researches on various adaptive reclosing circuit breakers have been actively conducted to pre-identify the types of accidents between instantaneous and permanent accidents, and most of them are fast Fourier transformation of wave voltage and current and wavelets. Signal processing techniques such as wavelet transformation have been applied.

However, in the process of continually shutting down and reclosing the circuit according to a predetermined operating sequence, a large fault current flows into the equipment of the power system, thus adversely affecting the facility, or reopening the circuit. Causing adverse effects on computer systems and precision instruments.

The present invention has been made to solve the above problems, a relatively small accident that is converted to a low voltage to the system through the auxiliary low voltage bypass circuit bypassing the main reclose circuit breaker during the dead time interval of the main reclose circuit breaker In addition to the continuous application of current, the magnitude of current is measured to determine instantaneous and permanent accidents.

As a result of the discrimination, in case of a momentary accident, the main reclosing circuit breaker applies a reclosing signal preset so that the switch is turned on. In case of a permanent accident, the switch is turned off by applying a permanent open signal.

The breaker using the active bypass recloser of the present invention for achieving the technical problem, by applying the accident current flowing into the second system through the main recloser breaker from the first system by applying a predetermined cutoff signal to the cutoff switch The switch is turned off to have a dead time period, the blocking signal is applied to the auxiliary low voltage bypass circuit, and the main reclosing circuit breaker and the main reclosing circuit breaker are turned on by receiving a resignation signal or a permanent open signal. Converts the high voltage of the fault current applied from the first system to the low voltage through the step-down transformer, continuously applies the fault current converted into the low voltage to the second system during the dead time period by the on / off operation of the high speed switch, Preset reclosing signal or permanent open signal by measuring magnitude of accidental current converted to low pressure It includes an auxiliary low voltage bypass circuit for applying to the main reclose circuit breaker.

In addition, the main reclosing circuit breaker according to the present invention, by measuring the magnitude of the current flowing into the second system through the main reclosing circuit breaker from the first system, if it exceeds the predetermined range it is determined that this is an accident current is a predetermined shutdown A fault current detection and control unit that applies a signal to the cutoff switch and, when the breaker is open, applies the signal to the auxiliary low voltage bypass circuit 200 and receives a reclose signal and a permanent open signal from the auxiliary low voltage bypass circuit, and the fault current. Detection and detection of the fault current from the controller to turn off the switch to have a dead time period, detection of fault current and the closing signal from the controller to turn on the switch, and permanently open signal to turn off the switch. It includes a switch.

In addition, the auxiliary low voltage bypass circuit according to the present invention includes a step-down transformer that bypasses the high voltage of the first system to the main reclose circuit breaker, converts the high voltage of the first system into a low voltage, and applies a current to the high speed switch, and received from a step-down transformer. The high-speed switch bypasses the main reclosing circuit breaker 100 according to a schedule of a predetermined operating sequence at predetermined intervals and applies it to the second system, and measures the magnitude of the current applied to the second system. Control unit for applying a predetermined reopening signal to the main reclosing circuit breaker 100 when the current is smaller than the minimum current, and applying a permanent open signal set to the main reclosing circuit breaker 100 when the magnitude of the measured current is greater than the minimum current. 230.

On the other hand, the circuit breaker operating method using the active bypass reclose of the present invention based on the above system, the main reclose breaker is pre-set by receiving the accident current flowing into the second system through the main reclose breaker from the first system The first step of applying the cutoff signal to the cutoff switch to have a dead time period, and applying the cutoff signal to the auxiliary low voltage bypass circuit, and after the auxiliary low voltage bypass circuit receives the cutoff signal from the main circuit breaker, The second process of converting the low voltage into a low voltage and continuously applying the fault current converted into the low voltage to the second system during the dead time period, and the controller of the auxiliary low voltage bypass circuit measures the magnitude of the current applied to the second system A third to apply a predetermined reclose signal or permanent open signal to the main reclose circuit breaker according to the magnitude of the current; And a fourth process in which the main reclose circuit breaker receives the reclose signal from the control unit of the auxiliary low voltage bypass circuit, turns on the switch, and receives the permanent open signal to permanently open the switch.

In addition, the first process, the fault current detection and control unit for measuring the magnitude of the current flowing into the second system from the first system through the main reclosing circuit breaker, and if the measured current exceeds the predetermined range, Determining that it is an accident current and applying a predetermined cutoff signal to the cutoff switch and the controller; turning off the switch according to the cutoff signal received by the cutoff switch to have a dead time; Receiving a reclosing signal from the control circuit of the bypass circuit to turn on the switch, and receiving a permanent opening signal to turn off the switch to permanently open the control circuit.

The third process may include: measuring, by the controller of the auxiliary low voltage bypass circuit, the magnitude of the current applied to the second system; and if the magnitude of the measured current is smaller than the predetermined minimum current, the fault current detection and controller Applying a preset reclosing signal, and detecting a fault current and applying a preset permanent opening signal to the controller if the magnitude of the measured current is greater than the preset minimum current.

According to the present invention as described above, the auxiliary low voltage bypass circuit continuously applies the fault current to the second system at a voltage lower than the rated voltage of the first system during the dead time stage of the main recloser, and measures the magnitude of the current. By controlling the reclosing of the main circuit breaker through this, it is possible to minimize the impact of the power equipment and at the same time accurately determine whether the accident and permanent accidents.

Also, in case of an instantaneous accident by using the magnitude of the current applied to the second system through the auxiliary low voltage circuit, a reopening signal preset to the main reopening circuit breaker is applied so that the switch is turned on. By applying the switch to be turned off, unnecessary reclosing operation can be prevented in the event of a permanent accident, thereby improving power quality.

Specific features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in the present specification and claims are defined in the technical spirit of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term in order to explain his invention in the best way. It should be interpreted as a meaning and a concept consistent with it. In addition, when it is determined that the detailed description of the known function and its configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, it should be noted that the detailed description is omitted.

1 is a block diagram illustrating a circuit breaker using an active bypass reclosing method according to the present invention, and FIG. 2 is a diagram illustrating a relationship between components of the circuit breaker using the active bypass reclosing method of the present invention.

The circuit breaker R using the active bypass reclosing method according to the present invention includes a main reclose circuit breaker 100 and an auxiliary low voltage bypass circuit 200 as illustrated in FIG. 1. Hereinafter, the description thereof will be omitted, but the term 'system' described in the present invention is assumed to collectively refer to a power system, a grounded power device, and a conductor.

Referring to FIG. 2, the main reclosing circuit breaker 100 has a current exceeding a preset range of a current flowing into the second system 20 from the first system 10 via the main reclosing circuit breaker (hereinafter, ' Fault current '), a predetermined cutoff signal is applied to the cutoff switch to turn off the switch to have a dead time period, and a cutoff signal is applied to the auxiliary low voltage bypass circuit 200 to receive a redo signal or a permanent open signal. To perform a function to turn on / off, includes a fault current detection and control unit 110 and the cutoff switch 120.

Specifically, the fault current detection and control unit 110 measures the magnitude of the current flowing into the second system 20 through the main reclosing circuit breaker from the first system 10 and exceeds the preset range to be the fault current. When it is determined that the predetermined cutoff signal is applied to the cutoff switch 120 and the breaker is opened, the cutoff signal is applied to the auxiliary low voltage bypass circuit 200.

The cutoff switch 120 detects the fault current and receives a cutoff signal from the controller 110 to turn off the switch so that the fault current has a dead time interval so that the fault current is not applied to the power system for a predetermined time. From the control unit 230 of the auxiliary low voltage bypass circuit 200 Re-closing is performed by receiving the signal of reclosing and re-closing, and permanently opening the switch by receiving the permanent opening signal.

The auxiliary low voltage bypass circuit 200 bypasses the main reclosing circuit breaker 100 from the first system 10 and is grounded with the second system in series to receive a blocking signal from the main reclosing circuit breaker 100 to receive the main reclosing circuit breaker. During the dead time period of (100), accident current is injected into the second system 20 by the on / off operation of the preset high speed switch, and the magnitude of the injected current is measured to re-open the reclosing signal or the permanent open signal. It performs a function applied to the closed circuit breaker 100, the step-down transformer 210, the high-speed switch 220 and includes a control unit 230 for controlling it.

Specifically, the step-down transformer 210 bypasses the main reclosing circuit breaker from the first system to step down the high voltage of the system to a very low low voltage and apply it to the high speed switch 220.

The high speed switch 220 bypasses the main reclosing circuit breaker 100 according to a schedule of a predetermined operating sequence at a predetermined interval and applies the incident current through the bypass low voltage source to the second system.

The controller 230 measures the magnitude of the current applied by the high speed switch 220 to the second system, and if the magnitude of the measured current is smaller than the predetermined minimum current, the controller 230 regards the accident current as the instantaneous accident detection and the controller ( When the magnitude of the measured current is greater than the preset minimum current, the accident current detection and the preset permanent open signal are applied to the controller 110.

Hereinafter, the experimental results of applying the circuit breaker using the active bypass reclose according to the present invention will be described with reference to FIGS. 3 to 6.

3A is an equivalent circuit of a positive impedance diagram in case of a power system accident when a conventional automatic reclosing circuit breaker is installed, and (b) is a circuit breaker according to the active bypass reclosing method of the present invention. Is a diagram showing the equivalent circuit of the normal impedance diagram in case of a power system accident in the case of a power system accident, and (c) is a diagram listing the details of the simulation of PSCAD / EMTDC for (b).

As shown in FIG. 3, the step-down transformer capacity of the auxiliary low voltage bypass circuit is 10 [kVA], the winding ratio is 23 / 0.23 [kV], and the leakage impedance is 10 [%]. According to the results of the three-phase accident analysis, the fault current of (A) power system applied with the existing recloser is 7.97 [kA], and the fault current flowing through the low voltage bypass circuit of (B) is 140.9 [A].

As can be seen in Figure 3, in the active bypass reclosing method, the fault current flowing through the low voltage bypass circuit is much smaller than the fault current flowing by the opening and closing operation of the existing recloser breaker does not adversely affect the power system equipment, The low voltage bypass circuit can safely and accurately check the inflow of the fault current.

4A is a fault current value flowing through the auxiliary low voltage bypass circuit when a three-phase accident occurs according to the capacity of the step-down transformer and the length of the line in the circuit of FIG. 3B. B) is a diagram showing the fault current flowing through the auxiliary low voltage bypass circuit when the fault resistance is varied from 0 to 10 [kΩ].

The result shown in FIG. 4 is a criterion for determining whether the accident is eliminated by the magnitude of current flowing through the low voltage bypass circuit when the active bypass reclosing method is applied. The result of the accident analysis is based on the power system of the power company. There may be some differences.

5 (a) shows the load current supplied through the auxiliary low voltage bypass circuit, and the load current is less than 2A and there is a significant difference from the fault current to determine whether the accident is eliminated by the magnitude of the current value flowing through the low voltage bypass circuit. It is suitable to

Figure 5 (b) is a three-phase instantaneous accident occurred in 7.5 seconds for 0.5 seconds, when the accident resistance value of 0.01 [kV], a diagram showing the fault current flowing through the auxiliary low voltage bypass circuit and re-close circuit breaker.

6 (A) shows a fault current flowing through the auxiliary low voltage bypass circuit and the reclosing circuit breaker when the three-phase instantaneous accident occurred for 7.5 seconds in 7.5 seconds and the resistance value of the accident was 10 [m]. ) Is a diagram showing the fault current flowing through the auxiliary low-voltage bypass circuit and the re-close circuit breaker when the ground fault instantaneous accident occurred for 7.5 seconds in 7.5 seconds and the resistance value is 0.01 [Ω].

Hereinafter, a circuit breaker operating method using the active bypass reclose of the present invention will be described with reference to FIGS. 7 to 9.

As shown in FIG. 7, the main reclosing circuit breaker 100 receives an accident current flowing into the second system 20 from the first system 10 via the main reclosing circuit breaker and cuts off the preset cutoff signal. The first process (S10), the auxiliary low voltage bypass circuit 200 to apply a dead time period, and apply the fault current detection and the blocking signal of the control unit 110 to the auxiliary low voltage bypass circuit 200, the main reclosing Bypassing the circuit breaker 100, the high voltage of the first system 10 is converted into low voltage through the step-down transformer, and the accident current converted into low voltage by the on / off operation of the high speed switch is continuously transferred to the second system during the dead time period. The second process of applying (S20), the third process of measuring the magnitude of the current applied to the second system and applying the reclosing signal or permanent opening signal to the main reclosing circuit breaker 100 according to the preset current ( S30) And a fourth process (S40) in which the main reclosing circuit breaker 100 receives the reclosing signal from the auxiliary low voltage bypass circuit 200 to turn on the switch and permanently opens the switch in response to the permanent opening signal.

Specifically, referring to FIG. 8, the process of detecting an accident current and the controller 110 measure the magnitude of the current flowing into the second system 20 through the main reclose circuit breaker from the first system 10 ( S11), when the measured current exceeds the preset range, it is determined that the fault current is applied to the cutoff switch 120 and the control unit 230 (S12).

Subsequently, the cutoff switch 120 turns off the switch according to the applied cutoff signal to have a dead time (S13), and the fault current detection and control unit 110 receives a reclosing signal from the auxiliary low voltage bypass circuit 200. The switch is turned on and is permanently opened by turning off the switch by receiving a permanent open signal (S14).

In operation S30, the controller 230 measures the magnitude of the current applied to the second system (S31). If the magnitude of the measured current is smaller than the predetermined minimum current, the fault current is detected. And a reclosing signal to the control unit 110 (S32), and if the magnitude of the measured current is greater than a predetermined minimum current, the accidental current detection and a permanent opening signal to the control unit 110 (S33).

As described above and described with reference to a preferred embodiment for illustrating the technical idea of the present invention, the present invention is not limited to the configuration and operation as shown and described as described above, it is a deviation from the scope of the technical idea It will be understood by those skilled in the art that many modifications and variations can be made to the invention without departing from the scope of the invention. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

1 is a view showing the configuration of a circuit breaker using the active bypass reclosing according to the present invention.

2 shows a relationship between components of a breaker using active bypass reclosing according to the present invention.

Figure 3 shows the details of the PSCAD / EMTDC simulation of the conventional automatic re-closure breaker (a) and the active bypass re-closure breaker (b) and (b) according to the present invention (c).

FIG. 4 shows an accident current value when a three-phase accident occurs according to the capacity of the step-down transformer and the length of the line in the circuit of FIG. 3 and an accident current when the accident resistance value is changed to 0 to 10 [kPa]. Figure showing values.

5 is a circuit diagram illustrating an auxiliary low voltage bypass circuit and a reclosing circuit breaker when a load current (a) and a three-phase instantaneous accident that occur through an auxiliary low voltage bypass circuit occur for 7.5 seconds in 7.5 seconds, and an accident resistance value is 0.01 [kΩ]. A diagram showing a fault current flowing through (b).

6 shows that the three-phase instantaneous accident occurs for 7.5 seconds for 0.5 seconds and the accident resistance value is 10 [Ω], and the first-line instantaneous instantaneous accident occurs for 7.5 seconds for 0.5 seconds, and the accident resistance value is 0.01. A diagram showing the fault current flowing through the low voltage bypass circuit and reclosing circuit breaker in case of [B].

Figure 7 is a flow chart illustrating a circuit breaker operating method using the active bypass reclosing according to the present invention.

** Description of symbols for the main parts of the drawing **

R: Breaker using active bypass reclose 10: First system

20: 2nd system 100: main reclosing breaker

110: fault current detection and control unit 120: disconnect switch

200: auxiliary low voltage bypass circuit 210: step-down transformer

220: high speed switch 230: control unit

Claims (6)

In circuit breaker using active bypass reclosing, The accident current flowing into the second system 20 from the first system 10 through the main reclosing circuit breaker is applied, and a predetermined cutoff signal is applied to the cutoff switch to turn off the switch to have a dead time period. A main reclosing circuit breaker (100) for applying the auxiliary low voltage bypass circuit (200) to receive a re-route signal or a permanent open signal to turn on / off the switch; And Bypassing the main reclosing circuit breaker 100 converts the high voltage of the fault current applied from the first system to a low voltage through the step-down transformer 210, and converts the fault current converted to low voltage by the second system (20) It is continuously applied during the dead time period by the on / off operation of the high speed switch, and measures the magnitude of the accident current converted into the low pressure to transmit a predetermined reclosing signal or permanent opening signal to the main reclosing circuit breaker 100. An auxiliary low voltage bypass circuit 200 to be applied; Breaker using active bypass reclosure, characterized in that it comprises a. The method of claim 1, The main reclosing circuit breaker 100, Measures the magnitude of the current flowing into the second system 20 through the main reclosing circuit breaker from the first system 10 and determines that it is an accident current when the current exceeds the preset range, and cuts off the preset blocking signal. An accident current detection and control unit 110 applied to the auxiliary low voltage bypass circuit 200 and receiving a reclose signal and a permanent open signal from the auxiliary low voltage bypass circuit 200; And The fault current is detected and the fault current is applied from the control unit 110 to turn off the switch to have a dead time period, and the fault current is detected and the reclose signal is received from the control unit 110 to turn on the switch, and permanently open. Shut off switch 120 for continuously applying the signal to the switch off; Breaker using active bypass reclosing, characterized in that it further comprises. The method of claim 1, The auxiliary low voltage bypass circuit 200, A step-down transformer 210 which bypasses the main reclosing circuit breaker 100 to convert the high voltage of the first system 10 to a low voltage, and applies the accident current converted into the low voltage to the high speed switch 220; A high speed switch 220 for bypassing the main reclosing circuit breaker 100 and applying it to the second system according to a schedule of a predetermined operating sequence at predetermined intervals from an accident current applied from the step-down transformer 210; And When the magnitude of the current applied to the second system is smaller than a preset minimum current, a preset reclose signal is applied to the main reclose circuit breaker 100, and when the measured current is greater than the minimum current, A controller 230 for applying a predetermined permanent open signal to the main reclosing circuit breaker 100; Breaker using active bypass reclosing, characterized in that it further comprises. In the circuit breaker operation method using active bypass reclosing, The main reclosing circuit breaker receives the fault current flowing from the first system through the main reclosing circuit breaker and flows into the second system to apply a preset cutoff signal to the cutoff switch to have a dead time period, and the cutoff signal is applied to the auxiliary low voltage bypass circuit. Applying a first process; A second process of converting the high voltage of the fault current into a low voltage and continuously applying the fault current converted into a low voltage to the second system for the dead time period after the auxiliary low voltage bypass circuit receives the cutoff signal from the main recloser breaker; ; A third step of controlling, by the controller of the auxiliary low voltage bypass circuit, a magnitude of a current applied to the second system and applying a preset reclose signal or a permanent open signal to the main reclose circuit breaker according to a preset current; And A fourth step of the main reclose circuit breaker receiving a reclose signal from a controller of the auxiliary low voltage bypass circuit to turn on a switch, and permanently opening the switch by receiving a permanent open signal; Breaker operating method using an active bypass reclosure, comprising a. The method of claim 4, wherein The first process, Measuring, by the fault current sensing and control unit, the magnitude of the current flowing into the second system from the first system via the main reclosing circuit breaker; If the measured current exceeds a preset range, determining that it is an accident current and applying a predetermined cutoff signal to the cutoff switch and the controller; Turning off the switch according to the cutoff signal applied by the cutoff switch to have a dead time; And The accident current sensing and control unit receiving a reclosing signal from the control unit of the auxiliary low voltage bypass circuit to turn on the switch, and receiving the permanent open signal to turn off the switch to open permanently; Breaker operating method using an active bypass reclosure comprising a. The method of claim 4, wherein The third process, Measuring a magnitude of a current applied to the second system by a controller of the auxiliary low voltage bypass circuit; If the magnitude of the measured current is smaller than a preset minimum current, applying a preset reclosing signal to the fault current detection and control unit; And If the magnitude of the measured current is greater than a preset minimum current, applying a preset permanent open signal to the fault current detection and control unit; Breaker operating method using an active bypass reclosure, characterized in that it comprises a.

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