JP7318010B2 - DC circuit breaker - Google Patents

Description

Embodiments of the present invention relate to DC circuit breakers.

2. Description of the Related Art In recent years, electric power is transmitted through a DC power transmission network composed of a plurality of DC power transmission lines. When an accident occurs in a DC transmission network, only a specific transmission line may be cut off, and power may continue to be transmitted through the remaining transmission lines. In this regard, there is known a technique related to a direct current interrupting device that is used at a coupling point of a plurality of direct current transmission lines and interrupts current flowing through some or all of the plurality of direct current transmission lines.

However, although the conventional DC current interrupting device can interrupt the current flowing from each DC transmission line to the coupling point, it may be difficult to interrupt the current flowing from the coupling point to each DC transmission line.

WO2019/035180

A problem to be solved by the present invention is to provide a direct current interrupting device capable of interrupting bidirectional current at a coupling point of a plurality of direct current transmission lines.

A DC current interrupting device of an embodiment has a plurality of first mechanical contacts, a plurality of second mechanical contacts, a plurality of commutation circuits, a first semiconductor circuit breaker, and a second semiconductor circuit breaker. A first mechanical contact is provided on each of a plurality of DC power transmission lines that constitute a DC system. A second mechanical contact is provided between each of the plurality of first mechanical contacts and a common power transmission line commonly connected to the plurality of DC power transmission lines. Each of the plurality of commutation circuits has a capacitor, and a current flowing in a first direction from one of the plurality of DC transmission lines to the common transmission line, or the common It commutates the current flowing in the second direction from the transmission line to the DC transmission line. A first semiconductor circuit breaker has a first end connected to the common power transmission line and a second end connected to the plurality of DC power transmission lines, and cuts off current flowing in the first direction commutated by the commutation circuit. It is possible. A second semiconductor circuit breaker has a first end connected to each of the plurality of DC power transmission lines, a second end connected to the common power transmission line, and a current flowing in the second direction commutated by the commutation circuit. It can be cut off.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of a structure of the direct current interruption|blocking apparatus 1 of 1st Embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1 when the first DC transmission line LN1 through which the DC system current flows in the second direction is individually interrupted in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the capacitor C is charged in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the first DC power transmission line LN1 are electrically cut off in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when individually interrupting the third DC power transmission line LN3 in which the DC system current flows in the first direction in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the capacitor C is charged in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the third DC power transmission line LN3 are electrically cut off in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when an accident occurs on the common power transmission line LNc. FIG. 3 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC power transmission line LN through which the DC system current flows in the first direction is completely interrupted in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the capacitor C is charged in the first embodiment. FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. FIG. 3 is a diagram showing an example of a state of the DC current interrupting device 1 when a common power transmission line LNc and a DC power transmission line LN are electrically cut off; 4 is a flowchart showing an example of processing of the direct current interrupting device 1; It is a figure which shows an example of a structure of the direct current interruption|blocking apparatus 1a of 2nd Embodiment. It is a figure which shows an example of the state of the direct current interruption|blocking apparatus 1a in the scene which charges the capacitor|condenser C in 2nd Embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the first DC power transmission line LN1 are electrically cut off in the second embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when individually interrupting the third DC power transmission line LN3 through which the DC system current flows in the first direction in the second embodiment. It is a figure which shows an example of the state of the direct current interruption|blocking apparatus 1a in the scene which charges the capacitor|condenser C in 2nd Embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when the common power transmission line LNc and the third DC power transmission line LN3 are electrically cut off in the second embodiment; It is a figure which shows an example of the state of the direct current interruption|blocking apparatus 1a in the scene where abnormality has arisen in the common power transmission line LNc. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC power transmission line LN through which the DC system current flows in the first direction is completely interrupted in the second embodiment. It is a figure which shows an example of the state of the direct current interruption|blocking apparatus 1a in the scene which charges the capacitor|condenser C in 2nd Embodiment. FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. FIG. 3 is a diagram showing an example of a state of a DC current interrupting device 1a when a common power transmission line LNc and a DC power transmission line LN are electrically cut off; 4 is a diagram showing another example of the position of a reactor 80 in the direct current interrupting device 1. FIG. It is a figure which shows the other example of the position of the reactor in the direct current interrupting device 1a.

A DC circuit breaker according to an embodiment will be described below with reference to the drawings.

(First embodiment)
[Configuration of DC current interrupter 1]
FIG. 1 is a diagram showing an example of the configuration of a DC current interrupting device 1 according to the first embodiment. The DC current interrupting device 1 is, for example, a device that electrically connects or disconnects a plurality of DC power transmission lines that form a DC system and a common power transmission line LNc that couples these DC power transmission lines. After that, the DC current interrupting device 1 electrically connects the three DC power transmission lines of the first DC power transmission line LN1, the second DC power transmission line LN2, and the third DC power transmission line LN3 to the common power transmission line LNc. , or a device that cuts off.

Hereinafter, the configuration related to the first DC power transmission line LN1 is denoted by "-1" at the end of the code, the configuration related to the second DC power transmission line LN2 is denoted by "-2" at the end of the code, The configuration related to the third DC power transmission line LN3 will be described with the reference number ending with "-3". In the case of not distinguishing which DC power transmission line is the configuration, the description will be given without attaching a number below the hyphen. Moreover, when not distinguishing between the first DC power transmission line LN1, the second DC power transmission line LN2, and the third DC power transmission line LN3, they are referred to as the DC power transmission line LN.

The direct current interrupting device 1 includes a plurality of first mechanical contacts 10, a plurality of second mechanical contacts 20, a plurality of commutation circuits 30, a first semiconductor circuit breaker 40-R, and a second semiconductor circuit breaker. 40 -L, a plurality of arresters 50 , a plurality of first diodes 60 , a plurality of second diodes 70 , a plurality of reactors 80 , and a control section 100 . The numbers of the first mechanical contacts 10, the second mechanical contacts 20, the commutation circuits 30, the first diodes 60, the second diodes 70, and the reactors 80 provided in the direct current interrupting device 1 are The number corresponds to the number of DC transmission lines LN connected to the DC current interrupting device 1 (three in this case). Moreover, the number of arresters 50 provided in the DC current interrupting device 1 is the number corresponding to the number of semiconductor circuit breakers provided in the DC current interrupting device 1 (two in this case).

Hereinafter, the first semiconductor circuit breaker 40-R and the second semiconductor circuit breaker 40-L will be referred to as the semiconductor circuit breaker 40 when not distinguished from each other. It is also assumed that the direct current interrupting device 1 has two arresters, an arrester 50-R and an arrester 50-L. The arrester 50-R and the arrester 50-L are referred to as the arrester 50 when not distinguished from each other.

As shown in FIG. 1, the first mechanical contact 10-1 is provided on the first DC power transmission line LN1, the first mechanical contact 10-2 is provided on the second DC power transmission line LN2, and the first mechanical contact The contact 10-3 is provided on the third DC transmission line LN3. Further, the second mechanical contact 20-1 is provided between the common power transmission line LNc and the first mechanical contact 10-1, and the second mechanical contact 20-2 is provided between the common power transmission line LNc and the first mechanical contact. The second mechanical contact 20-3 is provided between the common transmission line LNc and the first mechanical contact 10-3.

An auxiliary disconnector MS may be further provided between each DC power transmission line LN and the first mechanical contact 10 . Hereinafter, it is assumed that an auxiliary disconnector MS is provided between each DC power transmission line LN and the first mechanical contact 10 . Specifically, an auxiliary disconnector MS-1 is provided between the first DC transmission line LN1 and the first mechanical contact 10-1, and the second DC transmission line LN2 and the first mechanical contact 10- 2, and an auxiliary disconnector MS-3 is provided between the third DC transmission line LN3 and the first mechanical contact 10-3.

The first mechanical contact 10 has a first terminal 10a and a second terminal 10b, the second mechanical contact 20 has a first terminal 20a and a second terminal 20b, and the auxiliary disconnector MS It has a first terminal MSa and a second terminal MSb. A second terminal MSb of the auxiliary disconnecting switch MS-1 is connected to the first DC transmission line LN1. The first terminal MSa of the auxiliary disconnector MS-1 and the second terminal 10b of the first mechanical contact 10-1 are connected to each other. The first terminal 10a of the first mechanical contact 10-1 and the second terminal 20b of the second mechanical contact 20-1 are connected to each other. A first terminal 20a of the second mechanical contact 20-1 is connected to the common power transmission line LNc. A second terminal MSb of the auxiliary disconnector MS-2 is connected to the second DC transmission line LN2. The first terminal MSa of the auxiliary disconnector MS-2 and the second terminal 10b of the first mechanical contact 10-2 are connected to each other. The first terminal 10a of the first mechanical contact 10-2 and the second terminal 20b of the second mechanical contact 20-2 are connected to each other. A first terminal 20a of the second mechanical contact 20-2 is connected to the common power transmission line LNc. A second terminal MSb of the auxiliary disconnecting switch MS-3 is connected to the third DC transmission line LN3. The first terminal MSa of the auxiliary disconnector MS-3 and the second terminal 10b of the first mechanical contact 10-3 are connected to each other. The first terminal 10a of the first mechanical contact 10-3 and the second terminal 20b of the second mechanical contact 20-3 are connected to each other. A first terminal 20a of the second mechanical contact 20-3 is connected to the common transmission line LNc.

The semiconductor circuit breaker 40 includes, for example, a plurality of (four in the figure) switching units connected in series with each other. Each switching unit includes a switching element and a diode connected in parallel. Specifically, the cathode of the diode and the collector of the switching element are connected to each other, and the anode of the diode and the emitter of the switching element are connected. The switching element is, for example, a semiconductor switching element such as an insulated gate bipolar transistor (hereinafter referred to as IGBT: Insulated Gate Bipolar Transistor). However, the switching elements are not limited to IGBTs. The switching element may be any element as long as it can realize self-extinguishing. In the following description, a case where the switching elements are IGBTs will be described. Further, in the following description, the emitter of the switching element of the switching section is also referred to as the "emitter of the switching section", and the collector of the switching element of the switching section is also referred to as the "collector of the switching section".

In the semiconductor circuit breaker 40, the emitter of the switching section and the collector of the switching section adjacent to the switching section are connected. The semiconductor circuit breaker 40 includes a first terminal 40a and a second terminal 40b. The first terminal 40a is connected to the collector of the end switching part among the plurality of switching parts of the semiconductor circuit breaker 40 and the cathode of the diode connected in parallel to the end switching part. The second terminal 40b includes the emitter of the switching section at the other end of the plurality of switching sections provided in the semiconductor circuit breaker 40, and the anode of the diode connected in parallel to the switching section at the other end. Connected.

In the following description, the ON state of the switching element provided in the semiconductor circuit breaker 40 is also described as "the semiconductor circuit breaker 40 is in the closed state", and the switching element provided in the semiconductor circuit breaker 40 is in the OFF state. is also described as "the semiconductor circuit breaker 40 is in an open state".

A second terminal 40b of the first semiconductor circuit breaker 40-R is connected to the common transmission line LNc. Also, the first terminal 40a of the first semiconductor circuit breaker 40-R is connected via the second diode 70 to the DC transmission line LN. Specifically, the first terminal 40a is connected to the cathodes of the second diodes 70-1 to 70-3. The anode of the second diode 70-1, the other end of the reactor 80-1, the second terminal 10b of the first mechanical contact 10-1, and the first terminal MSa of the auxiliary disconnector MS-1 are connected to each other. Connected. The anode of the second diode 70-2, the other end of the reactor 80-2, the second terminal 10b of the first mechanical contact 10-2, and the first terminal MSa of the auxiliary disconnector MS-2 are connected to each other. Connected. The anode of the second diode 70-3, the other end of the reactor 80-3, the second terminal 10b of the first mechanical contact 10-3, and the first terminal MSa of the auxiliary disconnector MS-3 are connected to each other. Connected.

Due to the connection relationship described above, the second diodes 70-1 to 70-3 allow current to flow in the first direction from the DC power transmission line LN to the common power transmission line LNc, and allow the current to flow from the common power transmission line LNc to the DC power transmission line LN in the second direction. block the current flowing in the direction Hereinafter, the direction from the DC power transmission line LN to the common power transmission line LNc is also referred to as the “first direction” or “inward”, and the direction from the common power transmission line LNc to the DC power transmission line LN is referred to as the “second direction” or “outward”. direction” is also described.

A first terminal 40a of the second semiconductor circuit breaker 40-L is connected to the common transmission line LNc. Also, the second terminal 40b of the second semiconductor circuit breaker 40-L is connected to the DC transmission line LN via the first diode 60 and the reactor 80. As shown in FIG. Specifically, the second terminal 40b is connected to the anodes of the first diodes 60-1 to 60-3. The cathode of the first diode 60-1, the second terminal 30b of the commutation circuit 30-1, and one end of the reactor 80-1 are connected to each other, and the other end of the reactor 80-1 and the first mechanical The second terminal 10b of the contact 10-1 and the first terminal MSa of the auxiliary disconnector MS-1 are connected to each other. The cathode of the first diode 60-2, the second terminal 30b of the commutation circuit 30-2, and one end of the reactor 80-2 are connected to each other. The second terminal 10b of the contact 10-2 and the first terminal MSa of the auxiliary disconnector MS-2 are connected to each other. The cathode of the first diode 60-3, the second terminal 30b of the commutation circuit 30-3, and one end of the reactor 80-3 are connected to each other. The second terminal 10b of the contact 10-3 and the first terminal MSa of the auxiliary disconnector MS-3 are connected to each other.

Due to the connection relationship described above, the first diodes 60-1 to 60-3 allow current to flow from the common power transmission line LNc to the DC power transmission line LN, and current to flow from the DC power transmission line LN to the common power transmission line LNc. prevent

The arrester 50-R is connected in parallel with the first semiconductor circuit breaker 40-R between the common transmission line LNc and the second diode 70. As shown in FIG. In addition, the arrester 50-L is connected in parallel with the second semiconductor circuit breaker 40-L between the common transmission line LNc and the first diode 60. As shown in FIG. Arrestor 50 absorbs surge energy generated by semiconductor circuit breaker 40 being controlled to be in an open state.

Due to the connection relationship described above, the first semiconductor circuit breaker 40-R is used when the arrester 50-R extinguishes the DC system current in the first direction that flows from the DC power transmission line LN to the common power transmission line LNc. Semiconductor circuit breaker 40-L is used to cause arrester 50-L to extinguish the DC system current flowing in the second direction from common power transmission line LNc to DC power transmission line LN.

The commutation circuit 30 includes a plurality of switching units (switching units 310a to 310d shown) and a capacitor C, for example. Each switching unit includes a switching element and a diode connected in parallel. The switching units 310c and 310a are connected in series between the positive and negative electrodes of the commutation circuit 30 in the order shown, and the switching units 310b and 310d are connected in the order shown. connected in series between the positive and negative electrodes of the current circuit 30 . The emitter of the switching section 310c and the collector of the switching section 310a are connected to each other. The emitter of switching section 310b and the collector of switching section 310d are connected to each other. The collector of the switching section 310c, the collector of the switching section 310b, and the positive electrode of the capacitor C are connected to each other. The emitter of the switching section 310a, the emitter of the switching section 310d, and the negative electrode of the capacitor C are connected to each other.

A first terminal 30a of the commutation circuit 30 is provided at a connection point between the collector of the switching section 310a and the emitter of the switching section 310c. A second terminal 30b of the commutation circuit 30 is provided at a connection point between the emitter of the switching section 310b and the collector of the switching section 310d.

The first terminal 30a of the commutation circuit 30-1, the second terminal 20b of the second mechanical contact 20-1, and the first terminal 10a of the first mechanical contact 10-1 are connected to each other. The first terminal 30a of the commutation circuit 30-2, the second terminal 20b of the second mechanical contact 20-2, and the first terminal 10a of the first mechanical contact 10-2 are connected to each other. The first terminal 30a of the commutation circuit 30-3, the second terminal 20b of the second mechanical contact 20-3, and the first terminal 10a of the first mechanical contact 10-3 are connected to each other.

The second terminal 30b of the commutation circuit 30-1 and the cathode of the first diode 60-1 are connected to each other, and the second terminal 30b of the commutation circuit 30-2 and the cathode of the first diode 60-2 are connected. The second terminal 30b of the commutation circuit 30-3 and the cathode of the first diode 60-3 are connected to each other. Thereby, a reactor 80 is provided between the second terminal 30b and the second terminal 20b.

The control unit 100 controls the opening and closing of the auxiliary disconnector MS, the first mechanical contact 10, the second mechanical contact 20, and the semiconductor circuit breaker 40, and controls the operation of the commutation circuit 30 (that is, the opening and closing of the switching units 310a to 310d). control), etc.

As shown in FIG. 1, in a state in which the common power transmission line LNc and the DC power transmission line LN are electrically connected by the DC current interruption device 1 (hereinafter referred to as normal conduction state), each part is in the following states. It's becoming
Auxiliary disconnector MS: closed state First mechanical contact 10: closed state Second mechanical contact 20: closed state Commutation circuit 30: off state Capacitor C provided in commutation circuit 30: charged state・ Semiconductor circuit breaker 40: open state

In the normal conduction state shown in FIG. 1, the DC system current in the second direction is flowing through the first DC power transmission line LN1 and the second DC power transmission line LN2. In addition, the DC system current in the first direction is flowing through the third DC power transmission line LN3.

The DC current interrupting device 1 performs various interrupting controls according to the direction of the DC system current flowing in the DC power transmission line LN to be interrupted, and interrupts the common power transmission line LNc and the DC power transmission line LN. The details of the control of the direct current interrupting device 1 will be described below.

[Individual blocking in the second direction]
FIG. 2 is a diagram showing an example of the state of the DC current interrupting device 1 when individually interrupting the first DC transmission line LN1 through which the DC system current flows in the second direction in the first embodiment. In the scene shown in FIG. 2, an abnormality occurs in the first DC power transmission line LN1. Abnormalities that occur in the DC power transmission line LN are, for example, abnormalities that occur due to accidents such as ground faults and short circuits. The control unit 100 receives a cutoff instruction signal from a control system (not shown). The control system is, for example, a system that controls the supply (interchange) of electric power between power systems. to send. The disconnection instruction signal is, for example, a signal that instructs the DC power transmission line LN to be electrically disconnected from the common power transmission line LNc. When the control unit 100 receives a cutoff instruction signal from the control system, the control unit 100 controls the first mechanical contact 10 and the second mechanical contact 20 provided on the target DC power transmission line LN to the open state, and controls the target DC Among the plurality of switching units 310 included in the commutation circuit 30 related to the power transmission line LN, the switching unit 310 corresponding to the direction of the DC system current flowing in the target DC power transmission line LN is controlled to be in the ON state.

The scene shown in FIG. 2 indicates that the disconnection instruction signal electrically disconnects the first DC power transmission line LN1 and the common power transmission line LNc. When the DC system current flowing in the DC power transmission line LN to be cut off (in this case, the first DC power transmission line LN1) is in the second direction, the control unit 100 controls each unit included in the DC current cutoff device 1 as follows. to control the state. The operation of the commutation circuit 30 when the DC system current is in the first direction will be described later.
・ Auxiliary disconnector MS-1: closed ・ First mechanical contact 10-1: open ・ Second mechanical contact 20-1: open ・ Switching units 310a and 310b of commutation circuit 30-1: ON・Switching units 310c and 310d of commutation circuit 30-1: off state ・Semiconductor circuit breaker 40: open state Remains normally conducting.)

Under the control of the control unit 100 described above, the first mechanical contact 10-1 and the second mechanical contact 20-1 of the direct current interrupting device 1 are mechanically controlled to the open state, but the contacts are simply disconnected. However, since an arc occurs between the contacts, it cannot be electrically cut off. In this state, the control unit 100 operates the commutation circuit 30-1 to turn on the switching units 310a and 310b included in the commutation circuit 30-1. Then, the commutation circuit 30-1 discharges the electric charge stored in the capacitor C, and the electric charge is discharged from the positive electrode of the capacitor C through the switching unit 310b, the reactor 80-1, the first mechanical contact 10-1, and the switching unit 310a. form a circuit in which the current circulates through the path rt1 to the negative electrode of the capacitor C. This circuit is formed because the first diode 60-1 is connected to the reactor 80-1 in the direction described above, so that the common transmission line LNc is connected via the second semiconductor circuit breaker 40-L. This is because the diode of the first semiconductor circuit breaker 40-R blocks the current flowing in the direction of the common transmission line LNc. Since the current circulating in this circuit is the current flowing in the second direction from the common power transmission line LNc to the first DC power transmission line LN1 in the first mechanical contact 10-1 and in the opposite direction, the first mechanical contact 10 It acts to cancel the arc produced at -1. As a result, the current flowing through the first mechanical contact 10-1 becomes zero, and the first mechanical contact 10-1 is electrically interrupted.

FIG. 3 is a diagram showing an example of the state of the DC current interruption device 1 when charging the capacitor C in the first embodiment. When the first mechanical contact 10-1 is cut off both mechanically and electrically, the control unit 100 charges the capacitor C of the commutation circuit 30-1 in preparation for the next reclosing. At the same time, in order to commutate the DC system current to the second semiconductor circuit breaker 40-L that interrupts the DC system current in the second direction, each part provided in the DC current interrupting device 1 is controlled in the following states.
・ Auxiliary disconnector MS-1: closed ・ First mechanical contact 10-1: open ・ Second mechanical contact 20-1: open ・ Switching units 310a and 310b of commutation circuit 30-1: off・Switching units 310c and 310d of the commutation circuit 30-1: OFF state ・First semiconductor circuit breaker 40-R: Open state ・Second semiconductor circuit breaker 40-L: Closed state (configuration related to second DC transmission line LN2 , and the configuration related to the third DC power transmission line LN3 remains in the above-described normal conduction state.)

Under the control of the control unit 100 described above, the DC system current flowing from the common power transmission line LNc to the first DC power transmission line LN1 is controlled by the second mechanical contact 20-1, the switching unit 310c, the capacitor C, the switching unit 310d, and the reactor 80. -1 via route rt2. As a result, the DC current interrupting device 1 charges the capacitor C provided in the commutation circuit 30-1, and can sufficiently output the current that circulates through the path rt1 after the next reclosing.

In addition, as the second semiconductor circuit breaker 40-L is controlled to the closed state, the DC system current flowing from the common power transmission line LNc to the DC transmission line LN flows through the switching element of the second semiconductor circuit breaker 40-L, and It joins the path rt2 via the path rt3 via the first diode 60-1. As a result, the DC current interrupting device 1 gradually reduces the DC system current flowing from the common transmission line LNc to the path via the second mechanical contact 20-1, the commutation circuit 30, and the auxiliary disconnector MS-1. It can be commutated to the second semiconductor circuit breaker 40-L.

FIG. 4 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. In the scene of FIG. 4, the DC system current does not flow through the commutation circuit 30-1, and flows to the first DC transmission line LN1 via the second mechanical contact 20-1 and the commutation circuit 30-1. The resulting DC system current is commutated to the path rt4 through the second semiconductor circuit breaker 40-L and the first diode 60-1. Along with this, the second mechanical contact 20-1 is controlled to the open state both mechanically and electrically as the arc is extinguished by the current zero point.

After the DC system current in the second direction flowing from the common power transmission line LNc to the first DC power transmission line LN1 is commutated to the second semiconductor circuit breaker 40-L, the control unit 100 controls each part of the DC current interrupting device 1 to Control as follows.
・ Auxiliary disconnector MS-1: closed ・ 1st mechanical contact 10-1: open ・ 2nd mechanical contact 20-1: open ・ Commutation circuit 30-1: off ・ 1st semiconductor circuit breaker 40-R: Open state Second semiconductor circuit breaker 40-L: Closed state → Open state as it is.)

The surge energy generated when the second semiconductor circuit breaker 40-L is controlled to be open is absorbed by the arrester 50-L. Thereby, the DC current interrupting device 1 can electrically interrupt the common power transmission line LNc and the first DC power transmission line LN1. After the current flowing through the arrester 50-L becomes zero, the control unit 100 finally opens the auxiliary disconnecting switch MS-1. When the auxiliary disconnecting switch MS-1 is controlled to be open, no current is flowing, so no arcing occurs.

Note that the control unit 100 determines the timing at which the DC system current is commutated to the second semiconductor circuit breaker 40-L by the capacitor voltage of the capacitor C of the commutation circuit 30-1 or the voltage of the first mechanical contact 10-1. It may be determined (determined) based on the current, or may be determined (determined) based on the elapse of a predetermined time after the interruption operation of the first DC power transmission line LN1 is started.

FIG. 5 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the first DC power transmission line LN1 are electrically cut off in the first embodiment. As shown in FIG. 5, since the first mechanical contact 10-1, the second mechanical contact 20-1, and the auxiliary disconnector MS-1 are controlled to be open, the common power transmission line LNc and the first DC power transmission line LN1 is electrically cut off. As a result, the DC current interrupting device 1 suppresses the second DC power transmission line LN2 and the third DC power transmission line LN3 from being affected by the abnormality occurring in the first DC power transmission line LN1, The DC power transmission line LN allows the DC power supply to continue.

[Individual blocking in the first direction]
FIG. 6 is a diagram showing an example of the state of the DC current interrupting device 1 when individually interrupting the third DC transmission line LN3 in which the DC system current flows in the first direction in the first embodiment. In the scene shown in FIG. 6, an abnormality occurs in the first DC power transmission line LN1. The control unit 100 receives a shutdown instruction signal from the control system.

The scene shown in FIG. 6 indicates that the disconnection instruction signal electrically disconnects the third DC power transmission line LN3 and the common power transmission line LNc. When the DC system current flowing in the DC power transmission line LN to be cut off (in this example, the third DC power transmission line LN3) is in the first direction, the control unit 100 controls each unit included in the DC current cutoff device 1 as follows. control to a good state.
・ Auxiliary disconnector MS-3: closed ・ First mechanical contact 10-3: open ・ Second mechanical contact 20-3: open ・ Switching units 310a and 310b of commutation circuit 30-3: off・Switching units 310c and 310d of commutation circuit 30-3: ON state ・Semiconductor circuit breaker 40: Open state Remains normally conducting.)

Under the control of the control unit 100 described above, the first mechanical contact 10-3 and the second mechanical contact 20-3 of the direct current interrupting device 1 are mechanically controlled to the open state, but the contacts are simply disconnected. However, since an arc occurs between the contacts, it cannot be electrically cut off. In this state, the control unit 100 operates the commutation circuit 30-3 to turn on the switching units 310c and 310d included in the commutation circuit 30-3. Then, the commutation circuit 30-3 discharges the electric charge stored in the capacitor C, and the electric charge is discharged from the positive electrode of the capacitor C through the switching unit 310c, the first mechanical contact 10-3, the reactor 80-3, and the switching unit 310d. rt5 to the negative electrode of the capacitor C to form a circuit in which the current circulates. The current that circulates in this circuit is the current that flows in the first direction from the third DC power transmission line LN3 to the common power transmission line LNc at the first mechanical contact 10-3, and the current flows in the first direction. It acts to cancel the arc produced at -3. As a result, the current flowing through the first mechanical contact 10-3 becomes zero, and the first mechanical contact 10-3 is electrically interrupted.

FIG. 7 is a diagram showing an example of the state of the DC current interruption device 1 when charging the capacitor C in the first embodiment. When the first mechanical contact 10-3 is cut off both mechanically and electrically, the control unit 100 charges the capacitor C of the commutation circuit 30-3 in preparation for the next reclosing. At the same time, in order to commutate the DC system current to the first semiconductor circuit breaker 40-R that interrupts the DC system current in the first direction, each part provided in the DC current interrupting device 1 is controlled in the following states.
・ Auxiliary disconnector MS-3: closed ・ First mechanical contact 10-3: open ・ Second mechanical contact 20-3: open ・ Switching units 310a and 310b of commutation circuit 30-3: off・Switching units 310c and 310d of commutation circuit 30-3: off state ・First semiconductor circuit breaker 40-R: closed state ・Second semiconductor circuit breaker 40-L: open state (configuration related to first DC transmission line LN1 , and the configuration related to the second DC power transmission line LN2 remains in the above-described normal conduction state.)

Under the control of the control unit 100 described above, the DC system current flowing from the third DC power transmission line LN3 to the common power transmission line LNc is controlled by the auxiliary disconnecting switch MS-3, the reactor 80-3, the switching unit 310b, the capacitor C, the switching unit 310a, and the path rt6 through the second mechanical contact 20-3. As a result, the direct-current interrupting device 1 can charge the capacitor C provided in the commutation circuit 30-3, and can sufficiently output the current that circulates through the path rt5 after the next reclosing.

In addition, as the first semiconductor circuit breaker 40-R is controlled to the closed state, the DC system current flowing from the third DC transmission line LN3 to the common transmission line LNc flows through the second diode 70-3 and the first semiconductor circuit breaker 40-R. It flows through the path rt7 via the switching element of the circuit breaker 40-R. As a result, the DC current interrupting device 1 cuts the DC system current flowing from the third DC transmission line LN3 through the auxiliary disconnecting switch MS-3, the commutation circuit 30-3, and the second mechanical contact 20-3 to It can be gradually commutated to the first semiconductor circuit breaker 40-R.

FIG. 8 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. In the scene of FIG. 8, the DC system current does not flow in the commutation circuit 30-3, and the direct current flowing through the common transmission line LNc via the commutation circuit 30-3 and the second mechanical contact 20-3 System current is commutated to path rt7 via second diode 70-3 and first semiconductor circuit breaker 40-R. Along with this, the second mechanical contact 20-3 is controlled to an open state both mechanically and electrically as the arc is extinguished by the current zero point.

After the DC system current in the first direction flowing from the third DC power transmission line LN3 to the common power transmission line LNc is commutated to the first semiconductor circuit breaker 40-R, the control unit 100 controls each part of the DC current interrupting device 1 to Control as follows.
・ Auxiliary disconnector MS-3: closed ・ 1st mechanical contact 10-3: open ・ 2nd mechanical contact 20-3: open ・ Commutation circuit 30-3: off ・ 1st semiconductor circuit breaker 40-R: Closed state → Opened state Second semiconductor circuit breaker 40-L: Opened state (The configuration related to the first DC power transmission line LN1 and the configuration related to the second DC power transmission line LN2 are the above-described normal conduction state as it is.)

The surge energy generated by opening the first semiconductor circuit breaker 40-R is absorbed by the arrester 50-R. Thereby, the DC current interrupting device 1 can electrically interrupt the common power transmission line LNc and the third DC power transmission line LN3. After the current flowing through the arrester 50-R becomes zero, the control unit 100 finally opens the auxiliary disconnecting switch MS-3. When the auxiliary disconnecting switch MS-3 is controlled to be open, no current is flowing, so no arcing occurs.

FIG. 9 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the third DC power transmission line LN3 are electrically cut off in the first embodiment. As shown in FIG. 9, since the first mechanical contact 10-3, the second mechanical contact 20-3, and the auxiliary disconnector MS-3 are controlled to be open, the common power transmission line LNc and the third DC power transmission line LN3 is electrically cut off. As a result, the DC current interrupting device 1 suppresses the third DC power transmission line LN3 from being affected by an abnormality that occurs in the first DC power transmission line LN1, It is possible to continue the power supply of the DC system that exists on the end side that is not on the device 1 side.

[Regarding the complete interruption of the DC power transmission line LN in the first direction]
FIG. 10 is a diagram showing an example of the state of the DC current interrupting device 1 when an abnormality occurs in the common power transmission line LNc. In the scene shown in FIG. 10, an abnormality occurs in the common power transmission line LNc. Further, in the scene shown in FIG. 10 , the DC system current in the first direction flows through the first DC power transmission line LN1, the second DC power transmission line LN2, and the third DC power transmission line LN3. The control unit 100 controls each part of the direct current interrupting device 1 so as to interrupt the common power transmission line LNc and the direct current power transmission line LN.

FIG. 11 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC transmission line LN through which the DC system current flows in the first direction is completely interrupted in the first embodiment. The control unit 100 receives a disconnection instruction signal from the control system in response to the occurrence of an abnormality in the common power transmission line LNc. In the scene shown in FIG. 11, the disconnection instruction signal indicates to electrically disconnect the DC power transmission line LN (in this case, all three circuits) through which the DC system current flows in the first direction and the common power transmission line LNc. In this case, the control section 100 controls each section provided in the DC current interrupting device 1 so as to be in the following state.
Auxiliary disconnector MS: closed state First mechanical contact 10: open state Second mechanical contact 20: open state Switching units 310a and 310b of commutation circuit 30: OFF state Switching units of commutation circuit 30 310c, 310d: ON state Semiconductor circuit breaker 40: Open state

Although the first mechanical contact 10 and the second mechanical contact 20 of the DC current interrupting device 1 are mechanically controlled to be in an open state by the control of the control unit 100 described above, the contact between the contacts may be closed even if the contacts are simply disconnected. arcing, it cannot be cut off electrically. In this state, the control unit 100 operates the commutation circuit 30, so that the switching units 310c and 310d included in the commutation circuit 30 are turned on. Then, the commutation circuit 30 discharges the electric charge stored in the capacitor C, and from the positive electrode of the capacitor C to the negative electrode of the capacitor C via the switching unit 310c, the first mechanical contact 10, the reactor 80, and the switching unit 310d. (path rt5, paths rt8-rt9 in the drawing) to form a circuit in which current flows back. As a result, the current flowing through the first mechanical contact 10 becomes zero, and the first mechanical contact 10 is electrically interrupted.

FIG. 12 is a diagram showing an example of the state of the DC current interruption device 1 when charging the capacitor C in the first embodiment. When the first mechanical contact 10 is mechanically and electrically cut off, the control unit 100 charges the capacitor C of the commutation circuit 30 in preparation for the next reclosing, and the first In order to commutate the DC system current to the first semiconductor circuit breaker 40-R that cuts off the DC system current in the direction, each part provided in the DC current interrupting device 1 is controlled in the following states.
Auxiliary disconnector MS: closed state First mechanical contact 10: open state Second mechanical contact 20: open state Switching units 310a and 310b of commutation circuit 30: OFF state Switching units of commutation circuit 30 310c, 310d: OFF state ・First semiconductor circuit breaker 40-R: Closed state ・Second semiconductor circuit breaker 40-L: Open state

Under the control of the control unit 100 described above, the DC system current flowing from the DC transmission line LN to the common transmission line LNc is controlled by the auxiliary disconnecting switch MS, the reactor 80, the switching unit 310b, the capacitor C, the switching unit 310a, and the second mechanical contact. 20 (route rt6, route rt10-rt11 shown). As a result, the direct-current interrupting device 1 charges the capacitor C provided in the commutation circuit 30, and can sufficiently output the current to circulate through the path rt5 and the paths rt8-rt9 after the next reclosing.

In addition, as the first semiconductor circuit breaker 40-R is controlled to the closed state, the DC system current flowing from the DC transmission line LN to the common transmission line LNc flows through the second diode 70 and the first semiconductor circuit breaker 40-R. It flows through a route (route rt7, route rt12-rt13 in the figure) through the switching element of R. As a result, the DC current interrupting device 1 gradually reduces the DC system current flowing from the DC transmission line LN to the path via the auxiliary disconnecting switch MS, the commutation circuit 30, and the second mechanical contact 20 to the first semiconductor circuit breaker 40. -R.

FIG. 13 is a diagram showing an example of the state of the DC current interrupting device 1 when the DC system current is commutated to the semiconductor circuit breaker 40 according to the first embodiment. In the scene of FIG. 13 , the DC system current does not flow through the commutation circuit 30, and the DC system current flowing through the common transmission line LNc via the commutation circuit 30 and the second mechanical contact 20 is transferred to the second diode 70. , and the first semiconductor circuit breaker 40-R to the path rt7 and the path rt12-rt13. Along with this, the arc is extinguished by the zero point of the current, and the second mechanical contact 20 is mechanically and electrically controlled to the open state.

After all the DC system current in the first direction flowing from the DC power transmission line LN to the common power transmission line LNc is commutated to the first semiconductor circuit breaker 40-R, the control unit 100 controls each part of the DC current interrupting device 1 to Control as follows.
・ Auxiliary disconnector MS: closed ・ First mechanical contact 10: open ・ Second mechanical contact 20: open ・ Commutation circuit 30: off ・ First semiconductor circuit breaker 40-R: closed → open State ・ Second semiconductor circuit breaker 40-L: open state

The surge energy generated by opening the first semiconductor circuit breaker 40-R is absorbed by the arrester 50-R. Thereby, the DC current interrupting device 1 can electrically interrupt the common power transmission line LNc and the DC power transmission line LN. After the current flowing through the arrester 50-R becomes zero, the control unit 100 finally opens the auxiliary disconnector MS. When the auxiliary disconnecting switch MS is controlled to be open, no current is flowing, so no arc is generated.

FIG. 14 is a diagram showing an example of the state of the DC current interrupting device 1 when the common power transmission line LNc and the DC power transmission line LN are electrically cut off. As shown in FIG. 14, since the first mechanical contact 10, the second mechanical contact 20, and the auxiliary disconnector MS are controlled to be open, the common power transmission line LNc and the DC power transmission line LN are electrically cut off. be done. As a result, the DC current interrupting device 1 suppresses the DC power transmission line LN from being affected by an abnormality that occurs in the common power transmission line LNc, and prevents the DC power transmission line LN from being affected by an abnormality occurring in the common power transmission line LNc. It is possible to eliminate adverse effects on the DC system existing on the end side.

[Operation flow]
FIG. 15 is a flow chart showing an example of processing of the direct current interrupting device 1 . First, the control unit 100 receives a shutdown instruction signal from the control system (step S100). The control unit 100 waits until receiving the cutoff instruction signal. When receiving the disconnection instruction signal, the control unit 100 determines whether or not the disconnection instruction signal indicates an instruction to disconnect the plurality of DC power transmission lines LN (that is, whether it is an individual disconnection or not) (step S102).

When the control unit 100 determines that the disconnection instruction signal is a signal instructing to disconnect the plurality of DC power transmission lines LN, the control unit 100 controls the first line provided in the plurality of DC power transmission lines LN to be disconnected indicated by the disconnection instruction signal. The first mechanical contact 10 and the second mechanical contact 20 are each controlled to be open (step S104). Next, the control unit 100 operates each of the commutation circuits 30 corresponding to the plurality of DC power transmission lines LN to be cut off so as to cancel the current flowing through the DC power transmission lines LN to be cut off (step S106). Next, the control unit 100 controls the semiconductor circuit breaker 40 corresponding to the direction of the DC system current flowing through the target DC power transmission line LN (that is, the power transmission direction) to the closed state (step S108). The direction of the DC system current flowing through the target DC transmission line LN is the first direction or the second direction, and the semiconductor circuit breaker 40 corresponding to the first direction is the first semiconductor circuit breaker 40-R. , the semiconductor circuit breaker 40 corresponding to the second direction is the second semiconductor circuit breaker 40-L. At this time, the DC power transmission lines LN that are cut off by the instruction indicated by the cutoff instruction signal are all the DC power transmission lines LN in which the DC system current flows in the same direction.

Control unit 100 determines whether or not all of the DC system current flowing through target DC power transmission line LN has been commutated to corresponding semiconductor circuit breaker 40 (step S110). Control unit 100 waits until all of the DC system current flowing through target DC power transmission line LN is commutated to corresponding semiconductor circuit breaker 40 .

Note that the control unit 100 determines the timing at which the DC system current is commutated to the semiconductor circuit breaker 40 based on the capacitor voltage of the capacitor C of the commutation circuit 30-1 and the current of the auxiliary disconnector MS-1. Alternatively, it may be determined based on the lapse of a predetermined time after the target DC power transmission line LN has been cut off. Thus, when the semiconductor circuit breaker 40 is controlled to the closed state without performing the determination process, the control unit 100 does not need to perform the process of step S110.

When the control unit 100 determines that all of the DC system current flowing through the target DC transmission line LN has been commutated to the corresponding semiconductor circuit breaker 40 (when step S108 is not performed, it is determined at a predetermined timing). or after a predetermined time has passed), the corresponding semiconductor circuit breaker 40 is controlled to open (step S112). Next, the control unit 100 controls to open each of the auxiliary disconnecting switches MS provided in the plurality of DC power transmission lines LN to be cut off (step S114). Thereby, the DC current interrupting device 1 can interrupt the plurality of target DC power transmission lines LN and the common power transmission line LNc.

When the control unit 100 determines that the disconnection instruction signal is a signal instructing individual disconnection, the first mechanical contact 10 provided on the DC power transmission line LN to be disconnected instructed by the disconnection instruction signal, the first 2 The mechanical contact 20 is controlled to open (step S116). Next, the control unit 100 operates the commutation circuit 30 corresponding to the DC power transmission line LN to be cut off so as to cancel the current flowing through the DC power transmission line LN to be cut off (step S118). Next, the control unit 100 controls the semiconductor circuit breaker 40 corresponding to the direction of the DC system current flowing through the target DC power transmission line LN (that is, the power transmission direction) to the closed state (step S120). When the DC system current flowing through the target DC transmission line LN is commutated to the corresponding semiconductor circuit breaker 40, the control unit 100 controls the corresponding semiconductor circuit breaker 40 to the open state (step S122). Next, the control unit 100 controls the auxiliary disconnecting switch MS provided in the DC power transmission line LN to be cut off to open (step S124). As a result, the DC current interrupting device 1 can interrupt one DC power transmission line LN to be interrupted and the common power transmission line LNc.

[Summary of the first embodiment]
As described above, the direct current interrupting device 1 of the present embodiment includes a plurality of first mechanical contacts 10 (in this example, first mechanical contacts 10-1 to 10-3) and a plurality of second mechanical contacts 10-1 to 10-3. contact 20 (second mechanical contacts 20-1 to 20-3 in this example), a plurality of commutation circuits 30 (commutation circuits 30-1 to 30-3 in this example), and a first semiconductor It has a circuit breaker 40-R and a second semiconductor circuit breaker 40-L. The first mechanical contact 10 is provided on each of a plurality of DC power transmission lines LN (in this example, a first DC power transmission line LN1, a second DC power transmission line LN2, and a third DC power transmission line LN3) that constitute the DC system. . The second mechanical contacts 20 are respectively provided between the plurality of first mechanical contacts 10 and a common power transmission line LNc commonly connected to the plurality of DC power transmission lines LN. Each of the plurality of commutation circuits 30-1 to 30-3 has a capacitor C, and from one of the plurality of DC transmission lines LN, the DC transmission line LN to the common transmission line LNc. It commutates the current flowing in the first direction or the current flowing in the second direction from the common transmission line LNc to the DC transmission line LN. The first semiconductor circuit breaker 40-R has a first end connected to the common power transmission line LNc, a second end connected to a plurality of DC power transmission lines LN, and a current flowing in the first direction commutated by the commutation circuit 30. can be blocked. The second semiconductor circuit breaker 40-L has a first end connected to each of the plurality of DC transmission lines LN, a second end connected to the common transmission line LNc, and flow in the second direction in which the commutation circuit 30 is commutated. It is possible to cut off the current.

In a conventional DC current interrupting device, although the commutation circuit can commutate the DC system current flowing in the DC transmission line in the second direction, it is difficult to commutate the DC system current in the first direction. . Further, in the conventional DC current interrupting device, although the semiconductor circuit breaker can interrupt the DC system current flowing in the DC transmission line in the second direction, it is difficult to interrupt the DC system current in the first direction. .

According to the DC current interrupting device 1 of the present embodiment, the commutation circuit 30 of the full bridge circuit can commutate the DC system current in the first direction to the first semiconductor circuit breaker 40-R and the DC current in the second direction. System current can be commutated to the second semiconductor circuit breaker 40-L. Further, according to the DC current interrupting device 1 of the present embodiment, the first semiconductor circuit breaker 40-R can interrupt the DC system current in the first direction, and the second semiconductor circuit breaker 40-L can interrupt the DC system current in the second direction. Current can be interrupted. Therefore, the DC current interrupting device 1 of the present embodiment can interrupt the DC system current in both the first direction and the second direction in the common power transmission line LNc, which is the connection point of the plurality of DC power transmission lines LN. .

(Second embodiment)
A second embodiment will be described below with reference to the drawings. 1st Embodiment demonstrated the case where the direct current interruption|blocking apparatus 1 was equipped with the commutation circuit 30 of a full bridge circuit. In the second embodiment, the commutation circuit 30 includes a first commutation circuit 31 that commutates the DC system current in the first direction and a second commutation circuit 32 that commutates the DC system current in the second direction. A case of implementation will be described. In addition, about the structure similar to embodiment mentioned above, the same code|symbol is attached|subjected and description is abbreviate|omitted.

[Configuration of DC current interrupter 1a]
FIG. 16 is a diagram showing an example of the configuration of the DC current interrupting device 1a of the second embodiment. The commutation circuit 30 of the DC current interruption device 1a includes, for example, a first commutation circuit 31 for commutating the DC system current in the first direction and a second commutation circuit 32 for commutating the DC system current in the second direction. and Further, the direct current interrupting device 1a includes first reactors 81-1 to 81-3 and second reactors 82-1 to 82-3 instead of the reactors 80-1 to 80-3. The first commutator circuit 31 is an example of a "first commutator circuit", and the second commutator circuit 32 is an example of a "second commutator circuit".

The first commutation circuit 31 includes, for example, a plurality of switching units (switching units 310c and 310d illustrated), a plurality of diodes (diodes 320a and 320b illustrated), and a capacitor C. The second commutation circuit 32 includes a plurality of switching units (switching units 310a and 310b shown), a plurality of diodes (diodes 320c and 320d shown), and a capacitor C, for example.

In the first commutation circuit 31, the switching unit 310c and the diode 320a are connected in series between the positive electrode and the negative electrode of the first commutation circuit 31 in the order described, and the diode 320b and the switching unit 310d are connected in series. are connected in series between the positive and negative electrodes of the first commutation circuit 31 according to the order of description. The emitter of switching section 310c and the cathode of diode 320a are connected to each other. The anode of diode 320b and the collector of switching section 310d are connected to each other. The collector of the switching section 310c, the cathode of the diode 320b, and the positive electrode of the capacitor C are connected to each other. The anode of diode 320a, the emitter of switching section 310d, and the negative electrode of capacitor C are connected to each other.

A first terminal 31a of the first commutation circuit 31 is provided at a connection point between the emitter of the switching section 310c and the cathode of the diode 320a. A second terminal 31b of the first commutation circuit 31 is provided at a connection point between the anode of the diode 320b and the collector of the switching section 310d.

In the second commutation circuit 32, the diode 320c and the switching unit 310a are connected in series between the positive and negative electrodes of the commutation circuit 30 in the order described, and the switching unit 310b and the diode 320d By the order of description, they are connected in series between the positive and negative electrodes of the commutation circuit 30 . The anode of diode 320c and the collector of switching section 310a are connected to each other. The emitter of switching section 310b and the cathode of diode 320d are connected to each other. The cathode of diode 320c, the collector of switching section 310b, and the positive electrode of capacitor C are connected to each other. The emitter of switching section 310a, the anode of diode 320d, and the negative electrode of capacitor C are connected to each other.

A first terminal 32a of the second commutation circuit 32 is provided at a connection point between the collector of the switching section 310a and the anode of the diode 320c. A second terminal 32b of the second commutation circuit 32 is provided at a connection point between the emitter of the switching section 310b and the cathode of the diode 320d.

The first terminal 31a of the first commutation circuit 31 and the first terminal 32a of the second commutation circuit 32 are connected to the same location as the first terminal 30a described above.

The second terminal 31b of the first commutation circuit 31, the anode of the second diode 70, and one end of the second reactor 82 are connected to each other. Also, the other end of the second reactor 82, the second terminal 10b of the first mechanical contact 10, and the first terminal MSa of the auxiliary disconnector MS are connected to each other.

The second terminal 32b of the second commutation circuit 32, the cathode of the first diode 60, and one end of the first reactor 81 are connected to each other. Also, the other end of the first reactor 81, the second terminal 10b of the first mechanical contact 10, and the first terminal MSa of the auxiliary disconnector MS are connected to each other.

In a state where the common power transmission line LNc and the DC power transmission line LN are electrically connected by the DC current interrupting device 1a (hereinafter referred to as normal conduction state), each part is in the following states.
Auxiliary disconnector MS: closed state First mechanical contact 10: closed state Second mechanical contact 20: closed state First commutation circuit 31: OFF state Second commutation circuit 32: OFF state Capacitor C included in first commutation circuit 31: charged state Capacitor C included in second commutation circuit 32: charged state Semiconductor circuit breaker 40: open state Below, details of control of direct current interrupting device 1a explain.

[Individual blocking in the second direction]
In the scene shown in FIG. 16, an abnormality occurs in the first DC power transmission line LN1. When the control unit 100 receives a cutoff instruction signal from the control system, the control unit 100 controls the first mechanical contact 10 and the second mechanical contact 20 provided on the target DC power transmission line LN to the open state, and controls the target DC A switching unit that corresponds to the direction of the DC system current flowing in the power transmission line LN, and is provided in the switching units 310c and 310d included in the first commutation circuit 31 related to the target DC power transmission line LN, or in the second commutation circuit 32. One of the switching units 310a and 310b is controlled to be on.

The scene shown in FIG. 16 indicates that the disconnection instruction signal electrically disconnects the first DC power transmission line LN1 and the common power transmission line LNc. When the DC system current flowing in the DC power transmission line LN to be cut off (in this case, the first DC power transmission line LN1) is in the second direction, the control unit 100 controls each unit of the DC current cutoff device 1a as follows. to control the state. The operations of the first commutation circuit 31 and the second commutation circuit 32 when the DC system current is in the first direction will be described later.
・ Auxiliary disconnector MS-1: closed ・ 1st mechanical contact 10-1: open ・ 2nd mechanical contact 20-1: open ・ 1st commutation circuit 31-1: off ・ 2nd commutation Current circuit 32-1: ON state Semiconductor circuit breaker 40: Open state (The configuration relating to the second DC power transmission line LN2 and the configuration relating to the third DC power transmission line LN3 remain in the above-described normal conduction state.)

Under the control of the control unit 100 described above, the first mechanical contact 10-1 and the second mechanical contact 20-1 of the direct current interrupting device 1a are mechanically controlled to the open state. However, since an arc occurs between the contacts, it cannot be electrically cut off. In this state, the control unit 100 operates the second commutation circuit 32-1 to turn on the switching units 310a and 310b included in the second commutation circuit 32-1. Then, the second commutation circuit 32-1 discharges the charge stored in the capacitor C, and from the positive electrode of the capacitor C, the switching unit 310b, the first reactor 81-1, the first mechanical contact 10-1, and the switching unit 310b. A circuit is formed in which the current circulates through the path rt14 to the negative electrode of the capacitor C via the portion 310a. As a result, the current flowing through the first mechanical contact 10-1 becomes zero, and the first mechanical contact 10-1 is electrically interrupted.

FIG. 17 is a diagram showing an example of the state of the DC current interrupting device 1a when charging the capacitor C in the second embodiment. When the first mechanical contact 10-1 is cut off both mechanically and electrically, the control unit 100 closes the capacitor C of the second commutation circuit 32-1 in preparation for the next reclosing. In order to commutate the DC system current to the second semiconductor circuit breaker 40-L that cuts off the DC system current in the second direction while charging, each part provided in the DC current interrupting device 1a is controlled in the following states.
・ Auxiliary disconnector MS-1: closed ・ 1st mechanical contact 10-1: open ・ 2nd mechanical contact 20-1: open ・ 1st commutation circuit 31-1: off ・ 2nd commutation Current circuit 32-1: OFF state First semiconductor circuit breaker 40-R: Open state Second semiconductor circuit breaker 40-L: Closed state (configuration related to second DC transmission line LN2 and third DC transmission line LN3 The configuration pertaining to this means that the normal conduction state remains as described above.)

Under the control of the control unit 100 described above, the DC system current flowing from the common power transmission line LNc to the first DC power transmission line LN1 is controlled by the second mechanical contact 20-1, the diode 320c of the second commutation circuit 32-1, the capacitor C , the diode 320d and the path rt15 through the first reactor 81-1. As a result, the direct-current interrupting device 1a charges the capacitor C provided in the second commutation circuit 32-1, and can sufficiently output the current that circulates through the path rt14 after the next reclosing.

In addition, as the second semiconductor circuit breaker 40-L is controlled to the closed state, the DC system current flowing from the common power transmission line LNc to the first DC transmission line LN1 flows through the second semiconductor circuit breaker 40-L and the 1 joins the path rt15 via the path rt16 via the diode 60-1. As a result, the DC current interrupting device 1a allows the DC system current to flow from the common transmission line LNc to the path via the second mechanical contact 20-1, the second commutation circuit 32-1, and the auxiliary disconnector MS-1. can be gradually commutated to the second semiconductor circuit breaker 40-L.

FIG. 18 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. The DC system current no longer flows in the second commutation circuit 32-1, and the DC system that was flowing to the first DC transmission line LN1 via the second mechanical contact 20-1 and the second commutation circuit 32-1 Current is commutated to path rt16 via second semiconductor circuit breaker 40-L and first diode 60-1. Along with this, the second mechanical contact 20-1 is controlled to the open state both mechanically and electrically as the arc is extinguished by the current zero point.

After the DC system current in the second direction flowing from the common power transmission line LNc to the first DC power transmission line LN1 is commutated to the second semiconductor circuit breaker 40-L, the control unit 100 controls each part of the DC current interrupting device 1a to Control as follows.
・ Auxiliary disconnector MS-1: closed ・ 1st mechanical contact 10-1: open ・ 2nd mechanical contact 20-1: open ・ 1st commutation circuit 31-1: off ・ 2nd commutation Current circuit 32-1: OFF state First semiconductor circuit breaker 40-R: Open state Second semiconductor circuit breaker 40-L: Closed state → Open state (configuration related to second DC transmission line LN2 and third DC The configuration related to the power transmission line LN3 remains in the above-described normal conduction state.)

The surge energy generated when the second semiconductor circuit breaker 40-L is controlled to be open is absorbed by the arrester 50-L. Thereby, the DC current interrupting device 1a can electrically interrupt the common power transmission line LNc and the first DC power transmission line LN1. After the current flowing through the arrester 50-L becomes zero, the control unit 100 finally opens the auxiliary disconnecting switch MS-1. When the auxiliary disconnecting switch MS-1 is controlled to be open, no current is flowing, so no arcing occurs.

FIG. 19 is a diagram showing an example of the state of the DC current interrupting device 1a when the common power transmission line LNc and the first DC power transmission line LN1 are electrically cut off in the second embodiment.

[Individual blocking in the first direction]
FIG. 20 is a diagram showing an example of the state of the DC current interrupting device 1a when individually interrupting the third DC transmission line LN3 through which the DC system current flows in the first direction in the second embodiment. In the scene shown in FIG. 20, an abnormality occurs in the first DC power transmission line LN1. The control unit 100 receives a shutdown instruction signal from the control system.

The scene shown in FIG. 20 indicates that the disconnection instruction signal electrically disconnects the third DC power transmission line LN3 and the common power transmission line LNc. When the DC system current flowing in the DC power transmission line LN to be cut off (in this case, the third DC power transmission line LN3) is in the first direction, the control unit 100 controls each part of the DC current cutoff device 1a as follows. to control the state.
・ Auxiliary disconnector MS-3: closed ・ 1st mechanical contact 10-3: open ・ 2nd mechanical contact 20-3: open ・ 1st commutation circuit 31-3: ON ・ 2nd commutation Current circuit 32-3: OFF state Semiconductor circuit breaker 40: Open state (The configuration related to the first DC power transmission line LN1 and the configuration related to the second DC power transmission line LN2 remain in the normal conduction state described above.)

Under the control of the control unit 100 described above, the first mechanical contact 10-3 and the second mechanical contact 20-3 of the direct current interrupting device 1a are mechanically controlled to the open state. However, since an arc occurs between the contacts, it cannot be electrically cut off. In this state, the control unit 100 operates the first commutation circuit 31-3, thereby turning on the switching units 310c and 310d of the first commutation circuit 31-3. Then, the first commutation circuit 31-3 discharges the electric charge stored in the capacitor C, and from the positive electrode of the capacitor C, the switching unit 310c, the first mechanical contact 10-3, the second reactor 82-3, and the switching unit 310c. A circuit is formed in which the current circulates through the path rt17 to the negative electrode of the capacitor C via the portion 310d. As a result, the current flowing through the first mechanical contact 10-3 becomes zero, and the first mechanical contact 10-3 is electrically interrupted.

FIG. 21 is a diagram showing an example of the state of the DC current interrupting device 1a when charging the capacitor C in the second embodiment. When the first mechanical contact 10-3 is cut off both mechanically and electrically, the control unit 100 closes the capacitor C of the first commutation circuit 31-3 in preparation for the next reclosing. In order to commutate the DC system current to the first semiconductor circuit breaker 40-R that cuts off the DC system current in the first direction while charging, each part provided in the DC current interrupting device 1a is controlled in the following states.
・ Auxiliary disconnector MS-3: closed ・ 1st mechanical contact 10-3: open ・ 2nd mechanical contact 20-3: open ・ 1st commutation circuit 31-3: off ・ 2nd commutation Current circuit 32-3: OFF state First semiconductor circuit breaker 40-R: Closed state Second semiconductor circuit breaker 40-L: Open state (configuration related to first DC transmission line LN1 and second DC transmission line LN2 The configuration pertaining to this means that the normal conduction state remains as described above.)

Under the control of the control unit 100 described above, the DC system current flowing from the third DC power transmission line LN3 to the common power transmission line LNc is controlled by the auxiliary disconnecting switch MS-3, the second reactor 82-3, the diode 320b, the capacitor C, the diode 320a, and the path rt18 via the second mechanical contact 20-3. As a result, the direct-current interrupting device 1a charges the capacitor C provided in the first commutation circuit 31-3, and can sufficiently output the current that circulates through the path rt17 after the next reclosing.

In addition, as the first semiconductor circuit breaker 40-R is controlled to the closed state, the DC system current flowing from the third DC transmission line LN3 to the common transmission line LNc flows through the second diode 70-3 and the first semiconductor circuit breaker 40-R. It flows through path rt19 via the switching element of circuit breaker 40-R. As a result, the DC current interrupting device 1a allows the DC system current to flow from the third DC transmission line LN3 through the auxiliary disconnecting switch MS-3, the first commutation circuit 31-3, and the second mechanical contact 20-3. can be gradually commutated to the first semiconductor circuit breaker 40-R.

FIG. 22 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. The DC system current does not flow through the first commutation circuit 31-3, and the DC system current flowing through the common power transmission line LNc via the first commutation circuit 31-3 and the second mechanical contact 20-3 stops. , the second diode 70-3 and the first semiconductor circuit breaker 40-R to the path rt19. Along with this, the second mechanical contact 20-3 is controlled to an open state both mechanically and electrically as the arc is extinguished by the current zero point.

After the DC system current in the first direction flowing from the third DC power transmission line LN3 to the common power transmission line LNc is commutated to the first semiconductor circuit breaker 40-R, the control unit 100 controls each part of the DC current interrupting device 1a to Control as follows.
・ Auxiliary disconnector MS-3: closed ・ 1st mechanical contact 10-3: open ・ 2nd mechanical contact 20-3: open ・ 1st commutation circuit 31-3: off ・ 2nd commutation Current circuit 32-3: OFF state First semiconductor circuit breaker 40-R: Closed state → Open state Second semiconductor circuit breaker 40-L: Open state (configuration related to first DC transmission line LN1 and second DC The configuration related to the power transmission line LN2 remains in the above-described normal conduction state.)

The surge energy generated by opening the first semiconductor circuit breaker 40-R is absorbed by the arrester 50-R. Thereby, the DC current interrupting device 1a can electrically interrupt the common power transmission line LNc and the third DC power transmission line LN3. After the current flowing through the arrester 50-R becomes zero, the control unit 100 finally opens the auxiliary disconnecting switch MS-3. When the auxiliary disconnecting switch MS-3 is controlled to be open, no current is flowing, so no arcing occurs.

FIG. 23 is a diagram showing an example of the state of the DC current interrupting device 1a when the common power transmission line LNc and the third DC power transmission line LN3 are electrically cut off.

[Regarding the complete interruption of the DC power transmission line LN in the first direction]
FIG. 24 is a diagram showing an example of the state of the DC current interrupting device 1a when an abnormality occurs in the common power transmission line LNc. In the scene shown in FIG. 24, an abnormality has occurred in the common power transmission line LNc. In addition, in the scene shown in FIG. 24 , the DC system current in the first direction flows through the first DC power transmission line LN1, the second DC power transmission line LN2, and the third DC power transmission line LN3. The control unit 100 controls each part of the DC current interrupting device 1a so as to interrupt the common power transmission line LNc and the DC power transmission line LN.

FIG. 25 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC transmission line LN through which the DC system current flows in the first direction is completely interrupted in the second embodiment. The control unit 100 receives a disconnection instruction signal from the control system in response to the occurrence of an abnormality in the common power transmission line LNc. In the scene shown in FIG. 25, the disconnection instruction signal indicates that the DC power transmission line LN (in this case, all three circuits) through which the DC system current flows in the first direction and the common power transmission line LNc are electrically disconnected. In this case, the control section 100 controls each section of the DC current interrupting device 1a so as to be in the following state.
Auxiliary disconnector MS: closed state First mechanical contact 10: open state Second mechanical contact 20: open state First commutation circuit 31: ON state Second commutation circuit 32: OFF state Semiconductor Breaker 40: open state

Although the first mechanical contact 10 and the second mechanical contact 20 of the DC current interrupting device 1a are mechanically controlled to be in an open state by the control of the control unit 100 described above, the contact between the contacts may be closed even if the contacts are simply disconnected. arcing, it cannot be cut off electrically. In this state, the control unit 100 operates the first commutation circuit 31, so that the switching units 310c and 310d included in the first commutation circuit 31 are turned on. Then, the first commutation circuit 31 discharges the electric charge accumulated in the capacitor C, and the capacitor C is discharged from the positive electrode of the capacitor C via the switching portion 310c, the first mechanical contact 10, the second reactor 82, and the switching portion 310d. A circuit is formed in which the current circulates through the paths to the negative electrode of C (path rt17 and paths rt20-rt21 in the figure). As a result, the current flowing through the first mechanical contact 10 becomes zero, and the first mechanical contact 10 is electrically interrupted.

FIG. 26 is a diagram showing an example of the state of the DC current interruption device 1a when charging the capacitor C in the second embodiment. When the first mechanical contact 10 is mechanically and electrically cut off, the control unit 100 charges the capacitor C of the first commutation circuit 31 in preparation for the next reclosing. In order to commutate the DC system current to the first semiconductor circuit breaker 40-R that interrupts the DC system current in the first direction, each part provided in the DC current interrupting device 1a is controlled in the following states.
Auxiliary disconnector MS: closed state First mechanical contact 10: open state Second mechanical contact 20: open state First commutation circuit 31: off state Second commutation circuit 32: off state 1 semiconductor circuit breaker 40-R: closed state ・ 2nd semiconductor circuit breaker 40-L: open state

Under the control of the control unit 100 described above, the DC system current flowing from the DC power transmission line LN to the common power transmission line LNc is controlled by the auxiliary disconnecting switch MS, the second reactor 82, the diode 320b, the capacitor C, the diode 320a, and the second mechanical contact. 20 (path rt18 and paths rt22-rt23 shown). As a result, the direct-current interruption device 1a charges the capacitor C provided in the first commutation circuit 31, and can sufficiently output the current that circulates through the path rt17 and the paths rt20-rt21 after the next reclosing.

In addition, as the first semiconductor circuit breaker 40-R is controlled to the closed state, the DC system current flowing from the DC transmission line LN to the common transmission line LNc flows through the second diode 70 and the first semiconductor circuit breaker 40-R. It flows through a route (route rt19, route rt24-rt25 in the figure) through the switching element of R. As a result, the DC current interrupting device 1a gradually cuts off the DC system current flowing from the DC transmission line LN through the auxiliary disconnecting switch MS, the first commutation circuit 31, and the second mechanical contact 20. can be commutated to device 40-R.

FIG. 27 is a diagram showing an example of the state of the DC current interrupting device 1a when the DC system current is commutated to the semiconductor circuit breaker 40 according to the second embodiment. The DC system current no longer flows through the first commutation circuit 31, and the DC system current flowing through the common transmission line LNc via the first commutation circuit 31 and the second mechanical contact 20 is transferred to the second diode 70, and commutated to the path rt19 and the path rt24-rt25 via the first semiconductor circuit breaker 40-R. Along with this, the arc is extinguished by the zero point of the current, and the second mechanical contact 20 is mechanically and electrically controlled to the open state.

After all the DC system current in the first direction flowing from the DC power transmission line LN to the common power transmission line LNc is commutated to the first semiconductor circuit breaker 40-R, the control unit 100 controls each part of the DC current interrupting device 1a to Control as follows.
Auxiliary disconnector MS: closed state First mechanical contact 10: open state Second mechanical contact 20: open state First commutation circuit 31: off state Second commutation circuit 32: off state 1 semiconductor circuit breaker 40-R: closed → open ・ 2nd semiconductor circuit breaker 40-L: open

The surge energy generated by opening the first semiconductor circuit breaker 40-R is absorbed by the arrester 50-R. Thereby, the DC current interrupting device 1 can electrically interrupt the common power transmission line LNc and the DC power transmission line LN. After the current flowing through the arrester 50-R becomes zero, the control unit 100 finally opens the auxiliary disconnector MS. When the auxiliary disconnecting switch MS is controlled to be open, no current is flowing, so no arc is generated.

FIG. 28 is a diagram showing an example of the state of the DC current interrupting device 1a when the common power transmission line LNc and the DC power transmission line LN are electrically cut off. As shown in FIG. 28, since the first mechanical contact 10, the second mechanical contact 20, and the auxiliary disconnector MS are controlled to be open, the common power transmission line LNc and the DC power transmission line LN are electrically cut off. be done.

[Combination of DC transmission lines LN to be cut off]
In the above description, the DC current interrupting device 1 and the DC current interrupting device 1a are connected to any one of the first DC power transmission line LN1, the second DC power transmission line LN2, and the third DC power transmission line LN3. A case has been described in which the LN and the common transmission line LNc are cut off (that is, individual cutoff) or all of the DC transmission line LN and the common transmission line LNc are cut off (that is, total cutoff), but the present invention is not limited to this. . The DC current interrupting device 1 and the DC current interrupting device 1a, for example, among the DC transmission lines LN, interrupt two or more DC transmission lines LN in which the DC system current flows in the same direction and the common transmission line LNc. may be

For example, in the scenes shown in FIGS. 2 and 16, the DC system current flows in the second direction through the first DC power transmission line LN1 and the second DC power transmission line LN2. In this case, the DC current interrupting device 1 and the DC current interrupting device 1a may interrupt the first DC power transmission line LN1 and the second DC power transmission line LN2, and the common power transmission line LNc. In the scenes of FIGS. 2 and 16 , the process of interrupting the second DC power transmission line LN2 is the same as the process of interrupting the first DC power transmission line LN1 in the scenes of FIGS. 2 and 16 . In this case, after both the DC system current flowing through the first DC transmission line LN1 and the DC system current flowing through the second DC transmission line LN2 are commutated to the second semiconductor circuit breaker 40-L, the control unit 100 , to open the second semiconductor circuit breaker 40-L. As a result, the DC current interrupting device 1 and the DC current interrupting device 1a are connected to two or more DC power transmission lines LN (in this case, the first DC power transmission line) in which the DC system current flows in the same direction (in this case, the second direction). LN1 and the second DC power transmission line LN2) can be cut off from the common power transmission line LNc.

In this example, the case where the same DC system current in the second direction flows through the first DC power transmission line LN1 and the second DC power transmission line LN2 has been described, but the present invention is not limited to this. When the same DC system current in the second direction flows through the first DC transmission line LN1 and the third DC transmission line LN3, the DC current interruption device 1 and the DC current interruption device 1a are connected to the first DC transmission line LN1. , and the third DC power transmission line LN3 and the common power transmission line LNc. Further, in a scene where a DC system current in the first direction flows through the first DC transmission line LN1 and a DC system current in the second direction flows through the second DC transmission line LN2 and the third DC transmission line LN3, the DC The current interrupting device 1 and the DC current interrupting device 1a may interrupt the second DC power transmission line LN2 and the third DC power transmission line LN3, and the common power transmission line LNc.

6 and 20, the DC system current flows in the first direction only through the third DC power transmission line LN3, and the first DC power transmission line LN1 and the second DC power transmission line LN2 are connected to the second DC power transmission line LN2. Although the case where the DC system current is flowing in the direction has been described, it is not limited to this, and in the scenes shown in FIG. 6 and FIG. When the DC system current is flowing and the DC system current in the second direction is flowing in the first DC transmission line LN1, the third DC transmission line LN3, the second DC transmission line LN2, and the common transmission line LNc and may be blocked. In the scenes of FIGS. 6 and 20, the process of interrupting the second DC power transmission line LN2 is the same as the process of interrupting the third DC power transmission line LN3 in the scenes of FIGS. In this case, the control unit 100 controls that both the DC system current flowing through the third DC transmission line LN3 and the DC system current flowing through the second DC transmission line LN2 are commutated to the first semiconductor circuit breaker 40-R. After that, the first semiconductor circuit breaker 40-R is controlled to open. As a result, the DC current interrupting device 1 has two or more DC power transmission lines LN (in this case, the third DC power transmission line LN3 and the second DC power transmission line LN3 in this case) in which the DC system current flows in the same direction (in this case, the first direction). line LN2) and the common transmission line LNc can be cut off.

In addition, when a DC system current in the first direction flows through the first DC transmission line LN1 and the third DC transmission line LN3, and a DC system current in the second direction flows through the second DC transmission line LN2, The DC current interrupting device 1 and the DC current interrupting device 1a may interrupt the first DC power transmission line LN1, the third DC power transmission line LN3, and the common power transmission line LNc. The process of disconnecting the DC power transmission line LN through which the DC system current flows in the first direction from the common power transmission line LNc by combining these is the same as the above-described process, and the hyphens at the end of the symbols may be replaced. Therefore, the description is omitted.

[Regarding the position where the reactor is installed]
In addition, in the DC current interrupting device 1 and the DC current interrupting device 1a, the reactor component of the reactor 80 is not only the commutation operation of the commutation circuit 30, but also the first semiconductor circuit breaker 40-R and the second semiconductor circuit breaker 40- It may be provided at a position acting on the blocking operation of L.

FIG. 29 is a diagram showing another example of the position of the reactor 80 in the direct current interrupting device 1. As shown in FIG. 29, one end of reactor 80, the second terminal 30b of commutation circuit 30, the cathode of first diode 60, and the anode of second diode 70 are connected to each other, and the other end of reactor 80 and the second terminal 30b are connected to each other. 2 terminals 20b are connected to each other. Since the reactor 80 is provided at this position, the reactor component of the reactor 80 causes the current in the first direction to be commutated to the first semiconductor circuit breaker 40-R while generating the reflux accompanying the operation of the commutation circuit 30 in the path rt26. The inductance of the path rt27 of the DC system current and the path rt28 of the DC system current in the second direction commutated to the second semiconductor circuit breaker 40-L can be unified.

FIG. 30 is a diagram showing another example of the position of the reactor in the DC current interrupting device 1a. In FIG. 30, the direct current interruption device 1a includes third reactors 83-1 to 83-3 instead of the first reactors 81-1 to 81-3 and the second reactors 82-1 to 82-3. . One end of the third reactor 83, the second terminal 31b of the first commutation circuit 31, the anode of the second diode 70, the second terminal 32b of the second commutation circuit 32, and the cathode of the first diode 60 are connected to each other, and the other end of the third reactor 83 and the second terminal 20b are connected to each other. By providing the third reactor 83 at this position, the reactor component of the third reactor 83 causes a return flow along the path rt29 associated with the operation of the first commutation circuit 31, or the operation of the second commutation circuit 32. A path rt31 of the DC system current in the first direction that is commutated to the first semiconductor circuit breaker 40-R and a second direction of the DC system current that is commutated to the second semiconductor circuit breaker 40-L. It is possible to unify the inductance with the path rt32 of the DC system current.

Here, when the reactor 80 is provided at the conventional position, the reactor component of the reactor 80 acts on the DC system current in the second direction commutated to the commutation circuit 30 and the second semiconductor circuit breaker 40-L. However, it did not act on the DC system current in the first direction commutated to the first semiconductor circuit breaker 40-R. In this case, the inductance of each DC power transmission line LN depends on the parasitic reactor of each DC power transmission line LN. It was not possible to unify or adjust the DC system current breaking speed of the circuit breaker 40-L. On the other hand, by providing the reactor 80 at the position shown in FIG. DC system current interrupting speed can be unified or adjusted.

Further, by providing the first reactor 81 and the second reactor 82 at the position of the third reactor 83, the DC current interrupting device 1a can reduce the number of parts and The third reactor 83 acts on the commutation operation of the current circuit 32 to unify the DC system current breaking speed of the first semiconductor circuit breaker 40-R and the DC system current breaking speed of the second semiconductor circuit breaker 40-L, or can be adjusted.

While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, as well as the scope of the invention described in the claims and equivalents thereof.

Claims (8)

a plurality of first mechanical contacts respectively provided on a plurality of DC power transmission lines constituting a DC system;
a second mechanical contact provided between each of the plurality of first mechanical contacts and a common power transmission line connected in common to the plurality of DC power transmission lines;
a plurality of commutation circuits, each commutation circuit having a capacitor, current flowing in a first direction from one of the plurality of DC transmission lines to the common transmission line; or a plurality of commutation circuits for commutating current flowing in a second direction from the common transmission line to the DC transmission line;
A first semiconductor circuit breaker having a first end connected to the common power transmission line, a second end connected to the plurality of DC power transmission lines, and capable of interrupting current flowing in the first direction commutated by the commutation circuit. and,
A second semiconductor breaker having first ends connected to the plurality of direct current transmission lines, a second end connected to the common power transmission line, and capable of blocking the current flowing in the second direction commutated by the commutation circuit. vessel and
A direct current interrupter. each of the plurality of commutation circuits has a plurality of switching elements,
further comprising a control unit for controlling open/closed states of the plurality of switching elements in the plurality of commutation circuits;
When the control unit turns off some or all of the plurality of first mechanical contacts,
Some switching elements among the plurality of switching elements are turned on to put the commutation circuit into an operating state, and current flows in the first direction or in the second direction using the charge charged in the capacitor. After commutating at least one of the flowing currents,
All of the plurality of switching elements are turned off to stop the commutation circuit, and the current flowing in the first direction and the current flowing in the second direction are not commutated;
The direct current interrupting device according to claim 1. Each of the plurality of commutation circuits includes a first commutator circuit that commutates the current flowing in the first direction and a second commutator circuit that commutates the current flowing in the second direction.
The direct current interrupting device according to claim 1. each of the plurality of commutation circuits further includes a plurality of switching elements and a plurality of diodes;
Further comprising a control unit for controlling the open/closed state of the switching element,
The control unit
The commutation circuit is activated by turning on the plurality of switching elements, and at least one of the current flowing in the first direction and the current flowing in the second direction is commutated using the charge charged in the capacitor. After letting it flow
all of the plurality of switching elements are controlled to be in an off state to stop the commutation circuit, and the current flowing in the first direction and the current flowing in the second direction are not commutated;
The DC current interrupting device according to claim 3. A plurality provided between the second end of the first semiconductor circuit breaker and the plurality of DC transmission lines and between the second end of the second semiconductor circuit breaker and the plurality of DC transmission lines, respectively further equipped with a reactor of
The commutation circuit forms a closed circuit with the reactor and the capacitor, and commutates current between the common power transmission line and the DC power transmission line.
The DC current interrupting device according to any one of claims 2 to 4. The commutation circuit forms a closed circuit with the reactor component of the DC power transmission line and the capacitor, and commutates current between the common power transmission line and the DC power transmission line.
The DC current interrupting device according to any one of claims 2 to 4. The open/close state of the first mechanical contact, the open/close state of the second mechanical contact, the operation of the commutation circuit, the open/close state of the first semiconductor circuit breaker, and the open/close state of the second semiconductor circuit breaker. and further comprising a control unit for controlling
The control unit
When electrically conducting the plurality of DC power transmission lines and the common power transmission line, the first mechanical contact and the second mechanical contact are both controlled to a closed state, and the commutation circuit is closed. Both are in a stopped state, and both the first semiconductor circuit breaker and the second semiconductor circuit breaker are controlled to an open state,
When electrically disconnecting the target DC power transmission line and the common power transmission line among the plurality of DC power transmission lines, the first mechanical contact and the second mechanical contact provided on the target DC power transmission line Control the mechanical contact to an open state, and put the commutation circuit corresponding to the target DC transmission line into an operating state,
When the current flowing in the target DC transmission line is the current in the first direction, the first semiconductor circuit breaker is closed and the commutation circuit transmits the target DC power transmission to the first semiconductor circuit breaker. After the current flowing through the line is commutated, the first semiconductor circuit breaker is controlled to be in an open state to electrically disconnect the target DC power transmission line and the common power transmission line;
When the current flowing in the target DC transmission line is the current in the second direction, the second semiconductor circuit breaker is closed and the commutation circuit transmits the target DC power transmission to the second semiconductor circuit breaker. After the current flowing through the line is commutated, the second semiconductor circuit breaker is controlled to be in an open state to electrically disconnect the target DC power transmission line and the common power transmission line;
The DC current interrupting device according to any one of claims 1 to 6. The open/close state of the first mechanical contact, the open/close state of the second mechanical contact, the operation of the commutation circuit, the open/close state of the first semiconductor circuit breaker, and the open/close state of the second semiconductor circuit breaker. and further comprising a control unit for controlling
The control unit
When electrically conducting the plurality of DC power transmission lines and the common power transmission line, the first mechanical contact and the second mechanical contact are both controlled to a closed state, and the commutation circuit is closed. Both are in a stopped state, and both the first semiconductor circuit breaker and the second semiconductor circuit breaker are controlled to an open state,
When all the currents flowing in the plurality of DC power transmission lines are in the same direction and the plurality of DC power transmission lines and the common power transmission line are electrically disconnected, the plurality of first mechanical contacts and the second mechanical contact are both controlled to be in an open state, and both the commutation circuits are in an operating state,
When all of the currents flowing through the plurality of DC power transmission lines are currents in the first direction, the first semiconductor circuit breaker is closed so that all of the currents flowing through the plurality of DC power transmission lines are After commutation to the first semiconductor circuit breaker by the commutation circuit, the first semiconductor circuit breaker is controlled to be in an open state to electrically disconnect the plurality of DC transmission lines and the common transmission line. ,
When all of the currents flowing in the plurality of DC power transmission lines are currents in the second direction, the second semiconductor circuit breaker is closed so that all of the currents flowing in the plurality of DC power transmission lines are After commutation to the second semiconductor circuit breaker by the commutation circuit, the second semiconductor circuit breaker is controlled to be in an open state to electrically disconnect the plurality of DC transmission lines and the common transmission line. ,
The DC current interrupting device according to any one of claims 1 to 7.

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