JP2010287460A - Commutation type direct current breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a commutation type direct current breaker which eliminates potential of faults in a main circuit, and is safe and low in cost. <P>SOLUTION: The commutation type direct current breaker includes: a main switch 3; a sub switch 4 connected in series to the main switch 3; a commutation circuit which is composed by a series circuit of a capacitor 6 and a commutation switch 5 and is connected in parallel to the main switch; a capacitor charging device 12 for charging the capacitor 6; and a commutation circuit forming switch 5a which is connected to the opposite side of the capacitor 6 to the commutation switch 5. When the main switch is closed, if the commutation switch 5 and the commutation circuit forming switch 5a are open, the commutation type direct current breaker is operated with the capacitor 6 and capacitor charging device 12 of the commutation circuit separated from the main circuit. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a commutation type DC circuit breaker in which a commutation switch is turned on after a main switch is opened and a vibration commutation current of a capacitor is superposed on a main circuit current to be interrupted.

  A commutation type DC circuit breaker is connected between a DC power source and a load, and a main switch that is energized by a main circuit current, a capacitor and a commutation switch that are electrically connected in series to the main switch. A commutation circuit connected in parallel, a capacitor charging device, and a control device for controlling them are arranged, and these devices are arranged in a switchboard (for example, see Patent Literature 1 and Patent Literature 2).

  When an excessive current flows in the DC circuit, the commutation switch is turned on after the main switch is opened, and the high frequency commutation current accompanying the discharge of the capacitor is supplied to the main switch. This commutation current is superimposed on the main circuit current, and a direct current is cut off by generating a current zero point in the main circuit current.

JP 2000-48686 A JP 2001-143581 A

  In the conventional commutation type DC circuit breaker, the main circuit and the commutation circuit are electrically connected through one commutation switch because the interruption method generates a zero point by the commutation from the capacitor and shuts off. Yes. For this reason, the capacitor of the commutation circuit and the charging circuit of the different power source for charging the capacitor are directly connected to the main circuit, and the voltage of the main circuit is constantly pressurized. For this reason, the main circuit may be affected by an abnormality in the commutation circuit and the charging circuit of the auxiliary circuit.

  In general, the main circuit voltage is 1500 V, which is higher than the auxiliary circuit charging circuit voltage 220 V, and the high voltage is also applied to the auxiliary circuit. Is needed.

  An object of the present invention is to provide a safe and low-cost commutation type DC circuit breaker that eliminates the potential for malfunction of the main circuit.

(1) In order to achieve the above object, the present invention comprises a main switch, a sub switch connected in series to the main switch, a capacitor, a commutation switch, and a series circuit. A commutation type DC circuit breaker having a commutation circuit connected in parallel and a capacitor charging device for charging the capacitor, wherein the commutation circuit is connected to the opposite side of the commutation switch via the capacitor. A commutation circuit forming switch provided, and when the main switch is closed, the commutation switch and the commutation circuit forming switch are opened, and the capacitor of the commutation circuit and the capacitor charging device are opened from the main circuit. It can be operated by disconnecting
With this configuration, the potential for malfunction of the main circuit can be eliminated, and the cost can be reduced safely.

  (2) In the above (1), it is preferable that the commutation switch and the commutation circuit forming switch are closed to connect the main circuit and the commutation circuit during the shut-off operation.

  According to the present invention, the potential for malfunction of the main circuit can be eliminated, and the device can be made safe and inexpensive.

1 is a single line diagram of a DC circuit showing a configuration of a commutation type DC circuit breaker according to an embodiment of the present invention. 1 is a structural diagram of a commutation type DC circuit breaker according to an embodiment of the present invention. It is a time chart which shows operation | movement of the commutation type DC circuit breaker by one Embodiment of this invention. 1 is an overall structural diagram of a commutation type DC circuit breaker according to an embodiment of the present invention. It is a structure figure of the example which accommodated the commutation type DC circuit breaker by one embodiment of the present invention in the switchboard.

Hereinafter, the configuration and operation of a commutation type DC circuit breaker according to an embodiment of the present invention will be described with reference to FIGS.
First, the configuration and operation of a commutation type DC circuit breaker according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a single line diagram of a DC circuit showing a configuration of a commutation type DC circuit breaker according to an embodiment of the present invention. FIG. 2 is a structural diagram of a main part of a commutation type DC circuit breaker according to an embodiment of the present invention. FIG. 3 is a time chart showing the operation of the commutation type DC circuit breaker according to the embodiment of the present invention.

  As shown in FIG. 1, the commutation type DC circuit breaker DS is connected between a DC power supply 9 and a load 10. The commutation type DC circuit breaker DS includes a main switch 3 through which a main circuit current is passed, a sub switch 4 connected in series with the main switch 3, and the main switch 3 and the sub switch 4. The connected saturable reactor 8, the energy absorption nonlinear resistor 7 connected in parallel to the series circuit of the main switch 3 and the saturable reactor 8, the current detector 27, the driving device 12, and the commutation Circuit.

  Here, the commutation circuit includes a capacitor 5 and a commutation switch 5 that are electrically connected in series, and is configured by connecting the series circuit to the main switch 3 in parallel. The capacitor 6 is charged in advance with a polarity opposite to that of the main circuit 1 by the capacitor charging device 11. The configuration described above is conventionally provided, but the present embodiment is further characterized in that a commutation circuit forming switch 5a is further provided in the commutation circuit. The commutation circuit forming switch 5 a is provided on the opposite side of the commutation switch 5 via the capacitor 6. The commutation circuit forming switch 5a is synchronized with the commutation switch 5, and is turned on and off before and after the main circuit current 1a is cut off.

  When an excessive current flows through the DC circuit, the current detector 27 detects it. When the drive device 12 interrupts the current of the main circuit 1, immediately after opening the main switch 3, the commutation switch 5 and the commutation circuit forming switch 5a are fired, and the capacitor 6, the commutation switch 5, The commutation circuit 2 of the saturable reactor 8 and the main switch 3 is formed, the capacitor 6 is discharged, and the high frequency commutation current 2a accompanying the discharge of the capacitor flows in the opposite direction to the main circuit current 1a. When this commutation current is superimposed on the main circuit current and the current of the main switch 3 reaches the zero point, the main switch 3 is extinguished and interrupted.

  As described above, since the commutation switch 5 and the commutation circuit formation switch 5a are normally opened, the commutation circuit 2 is disconnected from the main circuit 1, and the commutation circuit 2 is disconnected only when cut off. The main circuit 1 is connected. Therefore, since no unnecessary circuit is connected to the DC power supply 9 for operation, maintenance and inspection of the main circuit 1 and the commutation circuit 2 can be performed to maintain equipment and supply stable power. It is possible to reduce the manufacturing cost of parts considering insulation in manufacturing, improve work efficiency, and supply a stable product.

  Further, by separating the main circuit and the commutation circuit, the main circuit is not affected by an abnormality in the commutation circuit and the charging circuit of the auxiliary circuit. Furthermore, in general, the voltage of the main circuit is 1500 V, which is higher than the charging circuit voltage 220 V of the auxiliary circuit, and this voltage is also applied to the auxiliary circuit. However, since this is also unnecessary, maintenance inspection is easy at low cost.

  Next, the configuration of the commutation type DC circuit breaker equipped with the commutation circuit forming switch 5a of the present embodiment will be described with reference to FIG.

  The main switch 3 and the sub switch 4 are operated by the drive device 12 through the main shaft 25. The main switch 3 is provided with a commutation switch 5 via a main switch wiper spring 15 and a commutation switch wipe spring 17. Similarly, a commutation circuit forming switch 5a is also provided on the side of the sub switch 4 via a sub opening / closing wipe spring 16, a commutation circuit forming switch wipe spring 18, and an insulating rod 24.

  The DC power supply side main circuit connection terminal 19 and the DC load side main circuit terminal 20 constitute a capacitor connection terminal 22 via a commutation switch 5 and a commutation circuit forming switch 5a. When the main switch 3 and the sub switch 4 are in a closed state, the commutation switch 5 and the commutation circuit forming switch 5a are in an open circuit state, so that no voltage is applied to the capacitor connection terminal 22 side. It has become. In addition, the code | symbol 21 is a connection terminal of the saturable reactor 8, and the code | symbol 23 is a main circuit side connection terminal. Reference numeral 13 denotes a trip device.

  Next, the operation of the commutation type DC circuit breaker commutation type of this embodiment will be described with reference to FIG.

  In FIG. 3, FIG. 3 (A) shows the main circuit current, FIG. 3 (B) shows the commutation current, and FIG. 3 (C) shows the DC cutoff state by the commutation formula. FIG. 3D shows the open / close state of the main / sub switch, and FIG. 3E shows the open / close state of the commutation switch and the commutation circuit forming switch.

  For example, at time t1 in FIG. 3A, when the main circuit current increases due to a ground fault or the like, it is detected by the current detector 27 in FIG. 1 that an overcurrent has flowed. Then, as described in FIG. 2, the driving device 12 operates the main switch 3 and the sub switch 4 via the main shaft 25 at time t1, and as shown in FIG. To do.

  Thereafter, at time t2, the commutation switch 5 and the commutation circuit formation switch 5a are closed by the operation of the driving device 12, and the commutation current shown in FIG. 3B flows. Then, as shown in FIG. 3C, at time t3, the main switch is cut off at the current zero point.

  With the above configuration, in the circuit breaker that exhibits the breaking performance with the different power sources, the circuit is formed only at the time of breaking, so that the potential for mutual failure is eliminated and the operation becomes easy. Also, in maintenance inspections and parts replacement, the circuit can be disconnected, so that necessary locations can be handled in a short time and at a minimum cost.

Next, the overall configuration of the commutation type DC circuit breaker according to the present embodiment will be described with reference to FIG.
FIG. 4 is an overall structural diagram of a commutation type DC circuit breaker according to an embodiment of the present invention.

  As shown in FIG. 4, the commutation type DC circuit breaker 100 includes a switch driving device 12 that drives the main switch 3 and the auxiliary switch shown in FIG. 1, and a switch control that controls the switch driving device 12. Circuits 54, 55, 56, 57, a commutation switch 5 and a commutation circuit forming switch 5 a that are necessary for commutation, a commutation capacitor 6, a supersaturated reactor 8, and a non-linear resistance 7. Is mounted on the gantry 68.

  Here, the switch control circuits 54, 55, 56, 57 are arranged on the upper part of the switch drive device 12, and the commutation capacitor 6 is located behind the commutation switch 5 (on the gantry on which the commutation type DC circuit breaker is mounted). The erodible reactor 8 and the non-linear resistance 7 are arranged on the rear side of the main switch 3.

  A contactor 64 connected to the main circuit conductor disposed in the DC circuit breaker storage box is disposed behind the gantry 68, and the contactor 64 is disposed between the commutation capacitor 6 and the non-linear resistance 7. Is connected to the main switch 3 via

  The commutation capacitor 6 is mounted by dividing a capacity necessary for generating a zero point in the current flowing through the main switch into a plurality of capacitors. Other devices constituting the commutation type DC circuit breaker, for example, the non-linear resistance 7 and the supersaturated reactor 8 can also be divided and mounted. Note that when mounting in a divided manner, the commutation type DC circuit breaker as a whole can be reduced in size by securing a predetermined air space distance so as to ensure insulation performance.

  Thus, the main switch 3 constituting the commutation type DC circuit breaker, the switch driving device 12 for driving the main switch, the switch control circuits 54, 55, 56, 57 for controlling the switch driving device 12, and By installing the commutation switch 5 and the commutation circuit forming switch 5a, the commutation capacitor 6, the supersaturated reactor 8 and the non-linear resistance 7 which are necessary equipment for commutation on the mount 68, a commutation type DC circuit breaker is provided. It can be handled as a DC circuit breaker that can be moved manually.

  For this reason, at the time of product manufacture, it is possible to reduce the part production cost and improve the work efficiency by mass production. In addition, a verification test can be performed with the DC breaker alone, and a stable product can be supplied.

Next, the configuration of an example in which the commutation type DC circuit breaker according to the present embodiment is housed in a switchboard will be described with reference to FIG.
FIG. 5 is a structural diagram of an example in which a commutation type DC circuit breaker according to an embodiment of the present invention is housed in a switchboard. The same reference numerals as those in FIG. 4 indicate the same parts.

  In FIG. 5, reference numeral 40 denotes a switchboard, which includes a front storage box 40A, a DC circuit breaker storage box 41, and a rear storage box 42A. A switchboard control unit 30A, terminal blocks 70A, 70B, and 70C and a front door 31 are arranged in the storage box 40A. In the DC circuit breaker storage box 41, the DC circuit breaker 100 shown in FIG. Reference numeral 66 denotes a partition plate that partitions between the DC circuit breaker 100 and the main circuit conductor disposed on the back side of the circuit breaker storage box. A main circuit conductor 67 is disposed on the back surface of the partition plate 66. The main circuit conductor 67 is connected to the bus 63 via the main switch 3. 61 is an overcurrent detector attached to the main circuit conductor. A cable connected to an external load (feed wire) is stored in the back storage box 42A. This cable is connected to the main circuit conductor 67 through a connection conductor 71. The cable connection conductor 71 is fitted with an instrument DC transformer 76, a DC current transformer 73A, and a feeder failure selection device 72.

  According to this configuration, the configuration of the DC circuit breaker storage box 41 is changed by changing the type, configuration, and arrangement of the devices installed in the front storage box 40A and the rear storage box 42A that constitute the switchboard 40. It is possible to change the specifications and applications of the DC circuit board. That is, the DC circuit breaker storage box 41 can be standardized. For this reason, the burden required for the design and manufacture of the distribution board for DC circuits can be reduced. In addition, the overall height of the switchboard can be reduced, and the DC circuit switchboard can be reduced in size, weight, and cost.

  Further, when performing maintenance inspection or replacement of parts of the switchboard 40, the front door disposed on the front face of the switchboard 40 is opened, and the movable commutation type DC circuit breaker is pulled out to the front storage box 40A side. As a result, the DC circuit breaker is disconnected from the main circuit conductor 67 at the contact 64, so that the entire commutation type DC circuit breaker can be safely inspected and parts can be replaced. Further, since the inside of the panel after the commutation type DC circuit breaker is drawn out cannot be brought close to the main circuit conductor by the partition plate 66, the internal inspection can be safely performed.

  As described above, according to this configuration, the commutation type DC circuit breaker can be configured as a single unit on one movable gantry. For this reason, mass production with the same design product becomes possible. For this reason, the design of a commutation type DC circuit breaker part becomes unnecessary in the switchboard which accommodates the said DC circuit breaker as a single unit.

  In this way, when the commutation type circuit breaker of this configuration is adopted, it becomes possible to standardize the DC circuit breaker when designing the DC circuit switchboard for different applications and specifications, and the DC circuit breaker storage box It is possible to provide a commutation type DC circuit breaker that can be reduced in size and weight, reduce the time and effort during design and manufacture, and can be easily maintained and inspected at low cost.

As described above, according to the present embodiment, the potential for malfunction of the main circuit can be eliminated, and the device can be made safe and low cost.

DESCRIPTION OF SYMBOLS 1 ... Main circuit 1a ... Main circuit current 2 ... Commutation circuit 2a ... Commutation current (reverse current)
DESCRIPTION OF SYMBOLS 3 ... Main switch 4 ... Sub switch 5 ... Commutation switch 5a ... Commutation circuit formation switch 6 ... Capacitor 7 ... Energy absorption nonlinear resistance 8 ... Saturable reactor 8
DESCRIPTION OF SYMBOLS 9 ... DC power supply 10 ... DC load 11 ... Capacitor charging device 12 ... Drive device 13 ... Trip device 14 ... Breaking spring 15 ... Main switch wipe spring 16 ... Sub switch wipe spring 17 ... Commutation switch wipe spring 18 ... Wipe spring 19 for commutation circuit forming switch ... DC power supply side main circuit connection terminal 20 ... DC load side main circuit connection terminal 21 ... Saturable reactor 8 connection terminal 22 ... Capacitor connection terminal 23 ... Main circuit side connection terminal 24 ... Insulating rod 25 ... Main shaft 100 ... Commutation type DC circuit breaker DS ... Commutation type DC circuit breaker

Claims (2)

A main switch, a sub-switch connected in series to the main switch, a commutation circuit composed of a capacitor and a commutation switch and connected in parallel to the main switch, and charging the capacitor A commutation type DC circuit breaker having a capacitor charging device,
The commutation circuit includes a commutation circuit forming switch provided on the opposite side of the commutation switch via the capacitor,
When the main switch is closed, the commutation switch and the commutation circuit forming switch are opened, and the capacitor and the capacitor charging device of the commutation circuit can be separated from the main circuit and operated. DC breaker. The commutation type DC circuit breaker according to claim 1,
A commutation type DC circuit breaker characterized in that the commutation switch and the commutation circuit formation switch are closed during a shut-off operation, and the main circuit and the commutation circuit are connected.

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