JP7404171B2

JP7404171B2 - DC current interrupter

Info

Publication number: JP7404171B2
Application number: JP2020114823A
Authority: JP
Inventors: 裕史児山; 崇裕石黒
Original assignee: Toshiba Energy Systems and Solutions Corp
Current assignee: Toshiba Energy Systems and Solutions Corp
Priority date: 2020-07-02
Filing date: 2020-07-02
Publication date: 2023-12-25
Anticipated expiration: 2040-07-02
Also published as: JP2022012760A

Description

本発明の実施形態は、直流電流遮断装置に関する。 Embodiments of the present invention relate to a DC current interrupting device.

近年、送電システムにおいて直流送電を行うことについて検討・導入が進められている。直流送電システムは、従来の交流送電システムに比べ、長距離大電力送電に適用した場合に、低コストで設置可能であり且つ送電損失が少ない高効率システムを構築することが可能である。その一方、直流送電においては系統事故の発生した個所を遮断・隔離することが難しい。直流電流では、電流がゼロを横切る点（ゼロ点）が生じないため、機械式接点では電流を容易に遮断できないためである。これを解決するため、様々な直流電流遮断装置が検討されている。 In recent years, consideration and introduction of DC power transmission in power transmission systems has been progressing. Compared to conventional AC power transmission systems, DC power transmission systems can be installed at low cost when applied to long-distance high-power power transmission, and can construct a highly efficient system with less power transmission loss. On the other hand, in DC power transmission, it is difficult to cut off and isolate the location where a system fault occurs. This is because with direct current, there is no point where the current crosses zero (zero point), so mechanical contacts cannot easily interrupt the current. In order to solve this problem, various DC current interrupting devices are being considered.

直流電流遮断装置を運転する際には、内部の電流情報を動作の制御に用いるために、電流を検出することが重要となる。しかし直流電流遮断装置は平常時には導通状態を保ち、直流送電線に事故が発生した場合にのみ遮断動作するものであるため、平常時には特段の動作が発生しない。したがって、電流検出に故障が発生していても、それを検知できるのは事故が発生した時である。事故時に正常に回線を遮断するためには、電流検出器の故障をいち早く検出する必要がある。 When operating a DC current interrupting device, it is important to detect the current in order to use internal current information to control the operation. However, since the DC current interrupting device maintains a conductive state under normal conditions and only performs the interrupting operation when an accident occurs on the DC transmission line, no special operation occurs during normal times. Therefore, even if a failure occurs in current detection, it can only be detected when an accident occurs. In order to properly shut down the line in the event of an accident, it is necessary to detect failure of the current detector as soon as possible.

特開２０１６－１６２７１３号公報Japanese Patent Application Publication No. 2016-162713

本発明が解決しようとする課題は、電流検出器の故障を早期に検出し、故障がある場合には速やかにシステムを保護停止させることができる直流電流遮断装置を提供することである。 The problem to be solved by the present invention is to provide a DC current interrupting device that can detect a failure of a current detector at an early stage and, if a failure occurs, promptly bring the system to a protective stop.

実施形態の直流電流遮断装置は、機械式接点または電気式接点と、半導体遮断器と、転流回路と、複数の電流検出器と、制御装置とを持つ。半導体遮断器は、前記機械式接点または電気式接点と並行に設けられている。転流回路は、前記機械式接点または電気式接点を流れる電流を前記半導体遮断器に転流させる。制御装置は、前記複数の電流検出器の検出値に基づいて前記機械式接点または電気式接点、前記半導体遮断器、および前記転流回路を制御し、前記直流電流遮断装置を流れる直流電流を遮断する。また、前記制御装置は、前記複数の電流検出器のうち一部または全部の前記電流検出器の検出値の変化度合いまたは、他の電流検出器の検出値との関係に基づいて前記複数の電流検出器のうち一部または全部に異常が生じているか否かを判定し、異常が生じていると判定した場合、前記直流電流を遮断するための一連の動作を停止する。 The DC current interrupting device of the embodiment includes a mechanical contact or an electrical contact, a semiconductor circuit breaker, a commutation circuit, a plurality of current detectors, and a control device. A semiconductor circuit breaker is provided in parallel with the mechanical contact or the electrical contact. The commutation circuit commutates the current flowing through the mechanical contact or the electrical contact to the semiconductor circuit breaker. The control device controls the mechanical contact or the electrical contact, the semiconductor circuit breaker, and the commutation circuit based on the detected values of the plurality of current detectors, and interrupts the direct current flowing through the direct current interrupting device. do. In addition, the control device controls the amount of current detected by the plurality of current detectors based on the degree of change in the detected values of some or all of the current detectors, or the relationship with the detected values of other current detectors. It is determined whether or not an abnormality has occurred in some or all of the detectors, and if it is determined that an abnormality has occurred, a series of operations for cutting off the DC current is stopped.

第１の実施形態の直流電流遮断装置１の構成の一例を示す図。FIG. 1 is a diagram showing an example of the configuration of a DC current interrupting device 1 according to a first embodiment. 直流電流遮断装置１の動作について説明するための図。FIG. 3 is a diagram for explaining the operation of the DC current interrupting device 1. FIG. 直流電流遮断装置１の動作について説明するための図。FIG. 3 is a diagram for explaining the operation of the DC current interrupting device 1. FIG. 直流電流遮断装置１の動作について説明するための図。FIG. 3 is a diagram for explaining the operation of the DC current interrupting device 1. FIG. 変形例の直流電流遮断装置１Ａの構成の一例を示す図。The figure which shows an example of the structure of 1 A of direct current interruption devices of a modification. 上位制御装置２００と制御装置１００との関係を示す図。FIG. 2 is a diagram showing the relationship between a higher-level control device 200 and a control device 100. 遮断動作時において制御装置１００により実行される処理の流れの一例を示すフローチャート。5 is a flowchart showing an example of the flow of processing executed by the control device 100 during a shutoff operation. 転流回路１１の他の構成例を示す図。The figure which shows the other example of a structure of the commutation circuit 11. 第２の実施形態に係る直流電流遮断装置１Ｂの構成の一例を示す図。The figure which shows an example of the structure of the DC current interruption device 1B based on 2nd Embodiment. 第３の実施形態に係る直流電流遮断装置１Ｃの構成の一例を示す図。The figure which shows an example of a structure of 1 C of direct current interruption devices based on 3rd Embodiment.

以下、実施形態の直流電流遮断装置を、図面を参照して説明する。 Hereinafter, a DC current interrupting device according to an embodiment will be described with reference to the drawings.

（第１の実施形態）
図１は、第１の実施形態の直流電流遮断装置１の構成の一例を示す図である。例えば、図の左側には送電設備が存在し、図の右側には需要家が存在する。この場合、通常であれば左側から右側に直流電流が流れる。電流遮断装置１は、例えば、転流回路１１、機械接点式の断路器１２、遮断器１３、半導体遮断器１４、アレスタ１５、ダイオード１６、リアクトル１７、補助断路器１８、および制御装置１００を備える。電流遮断装置１には、電流検出器Ｓ１～Ｓ６が取り付けられている。電流検出器Ｓ１～Ｓ６のそれぞれの検出値は制御装置１００に入力される。 (First embodiment)
FIG. 1 is a diagram showing an example of the configuration of a DC current interrupting device 1 according to the first embodiment. For example, power transmission equipment exists on the left side of the diagram, and consumers exist on the right side of the diagram. In this case, direct current normally flows from the left side to the right side. The current interrupting device 1 includes, for example, a commutation circuit 11, a mechanical contact type disconnector 12, a circuit breaker 13, a semiconductor circuit breaker 14, an arrester 15, a diode 16, a reactor 17, an auxiliary disconnector 18, and a control device 100. . The current interrupting device 1 is equipped with current detectors S1 to S6. The detection values of each of the current detectors S1 to S6 are input to the control device 100.

直流電流遮断装置１の第１端である節点ｄと第２端である節点ｃは、断路器１２と遮断器１３が直列に接続された第１線路と、半導体遮断器１４とアレスタ１５が並列に接続され、更にダイオード１６が直列に接続された第２線路とで並列に接続されている。また、第１線路における断路器１２と遮断器１３との間の節点ａと、第２線路におけるダイオード１６のカソード側の節点ｂとを接続する第３線路には、転流回路１１が設けられている。 A node d, which is the first end of the DC current interrupting device 1, and a node c, which is the second end, are connected to a first line in which a disconnector 12 and a circuit breaker 13 are connected in series, and a semiconductor circuit breaker 14 and an arrester 15 are connected in parallel. The second line is further connected in parallel with a second line connected in series with a diode 16. Further, a commutation circuit 11 is provided on a third line that connects a node a between the disconnector 12 and the circuit breaker 13 on the first line and a node b on the cathode side of the diode 16 on the second line. ing.

転流回路１１は、例えば、コンデンサ１１Ａ、ダイオード１１Ｂ、スイッチング部１１Ｃ、およびサイリスタ１１Ｄを備え、それらが図示する形態で接続されている。スイッチング部１１Ｃは、それぞれ、互いに並列に接続されたスイッチング素子とダイオードとを備える。サイリスタ１１Ｄは、オフ状態において、流れる電流を双方向に阻止し、オン状態において、節点ａから節点ｂに向けて流れる電流を許容し、その逆向きの電流を阻止する。転流回路１１のスイッチング部１１Ｃのオン・オフ制御は、制御装置１００によって行われる。 The commutation circuit 11 includes, for example, a capacitor 11A, a diode 11B, a switching section 11C, and a thyristor 11D, which are connected in the illustrated manner. Each of the switching units 11C includes a switching element and a diode that are connected in parallel to each other. Thyristor 11D blocks current flowing in both directions in the off state, and allows current to flow from node a to node b in the on state, and blocks current in the opposite direction. On/off control of the switching section 11C of the commutation circuit 11 is performed by the control device 100.

断路器１２と遮断器１３は、制御装置１００によって開極状態または閉極状態のいずれかに制御される。 The disconnector 12 and the circuit breaker 13 are controlled by the control device 100 to be in either an open state or a closed state.

半導体遮断器１４は、例えば、互いに直列に接続された複数（図では４つ）のスイッチング部を備える。スイッチング部は、それぞれ、互いに並列に接続されたスイッチング素子とダイオードとを備える。具体的には、ダイオードのカソードと、スイッチング素子のコレクタとが互いに接続され、ダイオードのアノードと、スイッチング素子のエミッタとが接続されている。スイッチング素子は、例えば、絶縁ゲートバイポーラトランジスタ（ＩＧＢＴ：Insulated Gate Bipolar Transistor）等の半導体スイッチング素子である。スイッチング素子は、ＩＧＢＴに限定されず、自己消弧を実現可能なスイッチング素子であれば、いかなる素子でもよい。半導体遮断器１４のスイッチング素子のオン・オフ制御は、制御装置１００によって行われる。 The semiconductor circuit breaker 14 includes, for example, a plurality of (four in the figure) switching sections connected in series with each other. Each of the switching sections includes a switching element and a diode that are connected in parallel to each other. 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 to each other. The switching element is, for example, a semiconductor switching element such as an insulated gate bipolar transistor (IGBT). The switching element is not limited to an IGBT, and may be any switching element that can realize self-extinguishing. On/off control of the switching elements of the semiconductor circuit breaker 14 is performed by the control device 100.

アレスタ１５は、半導体遮断器１４がオフ状態に制御されることにより、直流送電線ＤＬのインダクタンス１９の分のエネルギーに起因して発生するサージエネルギーを吸収する。ダイオード１６は、節点ｄから節点ｂに流れる電流を許容し、その逆向きの電流を阻止する。 The arrester 15 absorbs surge energy generated due to the energy of the inductance 19 of the DC power transmission line DL when the semiconductor circuit breaker 14 is turned off. Diode 16 allows current to flow from node d to node b, and blocks current in the opposite direction.

制御装置１００は、例えば、例えば、ＣＰＵ（Central Processing Unit）などのハードウェアプロセッサがプログラム（ソフトウェア）を実行することにより以下の機能を実現するものである。制御装置１００の機能のうち一部または全部は、ＬＳＩ（Large Scale Integration）やＡＳＩＣ（Application Specific Integrated Circuit）、ＦＰＧＡ（Field-Programmable Gate Array）、ＧＰＵ（Graphics Processing Unit）などのハードウェア（回路部；circuitryを含む）によって実現されてもよいし、ソフトウェアとハードウェアの協働によって実現されてもよい。プログラムは、予めＨＤＤ（Hard Disk Drive）やフラッシュメモリなどの記憶装置（非一過性の記憶媒体を備える記憶装置）に格納されていてもよいし、ＤＶＤやＣＤ－ＲＯＭなどの着脱可能な記憶媒体（非一過性の記憶媒体）に格納されており、記憶媒体がドライブ装置に装着されることで記憶装置にインストールされてもよい。 The control device 100 realizes the following functions by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of the functions of the control device 100 are implemented using hardware (circuit units) such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), and GPU (Graphics Processing Unit). ; circuitry), or may be realized by collaboration between software and hardware. The program may be stored in advance in a storage device (a storage device with a non-transitory storage medium) such as an HDD (Hard Disk Drive) or flash memory, or may be stored in a removable storage device such as a DVD or CD-ROM. It may be stored in a medium (non-transitory storage medium), and installed in the storage device by loading the storage medium into a drive device.

図２～図４を参照し、直流電流遮断装置１の動作について説明する。図２におけるＣＬ１は、通常送電時における電流の流れを示している。直流送電線ＤＬの電流は、第１端ｄ、節点ａ、および第２端ｃを通り、節点ｂを通らずに流れる。 The operation of the DC current interrupting device 1 will be explained with reference to FIGS. 2 to 4. CL1 in FIG. 2 indicates the flow of current during normal power transmission. The current of the DC power transmission line DL flows through the first end d, the node a, and the second end c without passing through the node b.

図３におけるＣＬ２は、直流電流遮断装置１の遮断動作時の第１段階における電流の流れを示している。例えば、制御装置１００は、上位の制御システムから遮断指示信号を受信すると、断路器１２と遮断器１３とを開極状態にし、転流回路１１を（スイッチング部１１Ｃを）オン状態にする。断路器１２と遮断器１３とを開極状態にしただけでは、接点間にアークが生じるため、断路器１２も遮断器１３も電気的に遮断された状態にはならない。しかしながら、転流回路１１がオン状態になると、転流回路１１は、コンデンサ１１Ａに蓄電されている電荷を放電し、コンデンサ１１Ａの正極からスイッチング部１１Ｃ－１（本図の説明においてのみハイフン以下の符号を示す）、節点ｂ、遮断器１３、節点ａ、スイッチング部１１Ｃ－２、を順に経てコンデンサ１１Ａの負極に至る回路を形成する。この回路が形成されるのは、リアクトル１７に対して上述した向きによってダイオード１６が接続されていることにより、節点ｂから節点ｄに流れる電流が阻止されるためである。この回路を還流する電流は、遮断器１３において通常送電時と同様に流れようとする電流と逆方向の電流であるため、遮断器１３に生じたアークを打ち消すように作用する。この結果、遮断器１３に流れる電流がゼロになり、遮断器１３が電気的にも遮断状態となる。 CL2 in FIG. 3 indicates the current flow in the first stage during the interrupting operation of the DC current interrupting device 1. For example, when the control device 100 receives a cutoff instruction signal from a higher-level control system, it opens the disconnector 12 and the circuit breaker 13, and turns on the commutation circuit 11 (the switching unit 11C). If only the disconnector 12 and the circuit breaker 13 are opened, an arc will be generated between the contacts, so that neither the circuit breaker 12 nor the circuit breaker 13 will be electrically disconnected. However, when the commutation circuit 11 is turned on, the commutation circuit 11 discharges the charge stored in the capacitor 11A, and connects the positive electrode of the capacitor 11A to the switching section 11C-1 (only in the explanation of this figure, the numbers below the hyphen) ), node b, circuit breaker 13, node a, and switching section 11C-2 to form a circuit that reaches the negative electrode of capacitor 11A in this order. This circuit is formed because the diode 16 is connected to the reactor 17 in the above-described direction, thereby blocking the current flowing from the node b to the node d. The current circulating in this circuit is a current in the opposite direction to the current flowing in the circuit breaker 13 as in the case of normal power transmission, so it acts to cancel the arc generated in the circuit breaker 13. As a result, the current flowing through the circuit breaker 13 becomes zero, and the circuit breaker 13 becomes electrically disconnected.

図４におけるＣＬ３は、直流電流遮断装置１の遮断動作時の第２段階における電流の流れを示している。図３に示す状態となった後、制御装置１００は、半導体遮断器１４をオン状態にし、転流回路１１をオフ状態にする。すると、コンデンサ１１Ａに蓄電されている電荷による電圧が、断路器１２を流れ続ける電流を減少させる方向に印加される。これによって、断路器１２を流れる電流が減少し、半導体遮断器１４の側の第２線路に転流する。最終的に断路器１２を流れる電流が全て半導体遮断器１４の側の第２線路に転流され、断路器１２を流れる電流がゼロになるため、断路器１２が電気的にも遮断状態となる。 CL3 in FIG. 4 indicates the current flow in the second stage of the interrupting operation of the DC current interrupting device 1. After entering the state shown in FIG. 3, the control device 100 turns on the semiconductor circuit breaker 14 and turns off the commutation circuit 11. Then, a voltage due to the charge stored in the capacitor 11A is applied in a direction that reduces the current that continues to flow through the disconnector 12. As a result, the current flowing through the disconnector 12 decreases and is commutated to the second line on the semiconductor circuit breaker 14 side. Finally, all the current flowing through the disconnector 12 is commutated to the second line on the semiconductor circuit breaker 14 side, and the current flowing through the disconnector 12 becomes zero, so the disconnector 12 becomes electrically cut off. .

図４に示す状態の後、制御装置１００は、半導体遮断器１４をオフ状態にする。これによって、直流電流遮断装置１を流れる電流が遮断される。遮断後、直流送電線ＤＬのインダクタンス１９の分のエネルギーは、アレスタ１５で消費される。その後、補助断路器１８が開極状態にされることで、遮断動作が完了する。 After the state shown in FIG. 4, the control device 100 turns the semiconductor circuit breaker 14 off. As a result, the current flowing through the DC current interrupting device 1 is interrupted. After the interruption, the energy corresponding to the inductance 19 of the DC power transmission line DL is consumed by the arrester 15. Thereafter, the auxiliary disconnector 18 is brought into an open state, thereby completing the disconnection operation.

制御装置１００は、例えば、上記説明した遮断動作を、電流検出器Ｓ１～Ｓ６のそれぞれの検出値に基づいて進行させる。ところが、前述したように通常送電時において制御装置１００は特段の制御を行わないため、電流検出器Ｓ１～Ｓ６の検出値も特段に変化するものではなく、遮断動作時に初めて異常を検知するということが生じ得る。直流電流遮断装置１の遮断動作においては制御タイミングの正確さが要求されるため、電流検出器の故障を早期に検出し、故障がある場合には速やかにシステムを保護停止させることが望ましい。 For example, the control device 100 advances the above-described shutoff operation based on the detection values of the current detectors S1 to S6. However, as described above, since the control device 100 does not perform any special control during normal power transmission, the detected values of the current detectors S1 to S6 do not change particularly, and an abnormality is detected for the first time during the interruption operation. may occur. Since accurate control timing is required in the interrupting operation of the DC current interrupting device 1, it is desirable to detect a failure of the current detector early and to immediately bring the system to a protective stop if there is a failure.

そこで、制御装置１００は、以下に説明するように、複数の電流検出器Ｓ１～Ｓ６のうち一部または全部の電流検出器の検出値の変化度合いまたは、他の電流検出器の検出値との関係に基づいて、複数の電流検出器Ｓ１～Ｓ６のうち一部または全部に異常が生じているか否かを判定し、異常が生じていると判定した場合、直流電流を遮断するための一連の動作を停止する。なお、直流電流遮断装置１は複数の電流検出器Ｓ１～Ｓ６の全てを備えている必要は無く、一部の電流検出器が省略されてもよいし、他の箇所に別の電流検出器が設けられてもよい。 Therefore, as described below, the control device 100 determines the degree of change in the detected values of some or all of the current detectors S1 to S6, or the degree of change in the detected values of the other current detectors. Based on the relationship, it is determined whether an abnormality has occurred in some or all of the plurality of current detectors S1 to S6, and if it is determined that an abnormality has occurred, a series of steps are performed to interrupt the DC current. Stop operation. Note that the DC current interrupting device 1 does not need to include all of the plurality of current detectors S1 to S6, and some of the current detectors may be omitted, or other current detectors may be provided at other locations. may be provided.

「一連の動作を停止する」とは、例えば、転流回路１１のスイッチング部１１Ｃと、半導体遮断器１４のスイッチング素子に与える全てのゲート信号をオフにすることを意味する。また、「一連の動作を停止する」際に、制御装置１００は、直流電流を遮断するための一連の動作を指示する上位制御装置２００（後述）と通信し、複数の電流検出器Ｓ１～Ｓ６のうち一部または全部に異常が生じている旨の情報を、上位制御装置２００に送信してもよい。 "Stopping a series of operations" means, for example, turning off all gate signals applied to the switching unit 11C of the commutation circuit 11 and the switching elements of the semiconductor circuit breaker 14. In addition, when "stopping a series of operations," the control device 100 communicates with a higher-level control device 200 (described later) that instructs a series of operations to cut off the DC current, and controls the multiple current detectors S1 to S6. Information indicating that an abnormality has occurred in some or all of them may be transmitted to the higher-level control device 200.

制御装置１００は、以下に示す判定処理Ａ～Ｅのうち一部または全部、或いは他の種類の判定処理を実行する。 The control device 100 executes some or all of the determination processes A to E described below, or other types of determination processes.

（判定処理Ａの第1例）
制御装置１００は、転流回路１１の状態をオフ状態からオン状態に、或いはオン状態からオフ状態に切り替えることで生じる、転流回路１１を流れる電流の変化期間における、転流回路１１を流れる電流を検出可能な電流検出器の検出値の変化度合いに基づいて、転流回路１１を流れる電流を検出可能な電流検出器に異常が生じているか否かを判定する。例えば、転流回路１１の状態をオフ状態からオン状態に切り替えた場合、一定期間の間、転流回路１１を流れる電流は、制御サイクルの到来ごとに一定に近い傾き（変化率）で増加する。オン状態からオフ状態に切り替えた場合はその逆である。この状態が継続する時間は実験等で予め求められており、制御装置１００は、例えば転流回路１１の状態を切り替えた時点を起点として、上記求められた時間よりも若干短い時間が経過する時点までを電流の変化期間として、上記の判定を行う。「転流回路１１を流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ３、Ｓ５、Ｓ２のうち一部または全部である。制御装置１００は、電流検出器Ｓ２を判定の対象とする場合、電流検出器Ｓ２の検出値は転流回路１１を流れる電流が増加するのに応じて低下するものであるため、電流検出器Ｓ２の検出値の低下量を判定の対象とする。 (First example of determination process A)
The control device 100 controls the current flowing through the commutation circuit 11 during a period when the current flowing through the commutation circuit 11 changes, which is caused by switching the state of the commutation circuit 11 from an off state to an on state or from an on state to an off state. Based on the degree of change in the detected value of the current detector capable of detecting current, it is determined whether an abnormality has occurred in the current detector capable of detecting the current flowing through the commutation circuit 11. For example, when the state of the commutation circuit 11 is switched from the off state to the on state, the current flowing through the commutation circuit 11 increases at a nearly constant slope (rate of change) every time a control cycle arrives for a certain period of time. . The opposite is true when switching from an on state to an off state. The time for which this state continues is determined in advance through experiments or the like, and the control device 100 determines, for example, a point in time when a slightly shorter time than the determined time has elapsed, starting from the point in time when the state of the commutation circuit 11 is switched. The above determination is made with the period up to this period as the current change period. The "current detector capable of detecting the current flowing through the commutation circuit 11" is, for example, some or all of the current detectors S3, S5, and S2. When the control device 100 uses the current detector S2 as a determination target, the detected value of the current detector S2 decreases as the current flowing through the commutation circuit 11 increases. The amount of decrease in the detected value of is the subject of determination.

制御装置１００は、電流の変化期間における、転流回路１１を流れる電流を検出可能な電流検出器の検出値の制御サイクルごとの傾き（直前の制御サイクルに対する変化率）が閾値未満である場合、当該電流検出器に異常が生じていると判定する。これに代えて、制御装置１００は、電流の変化期間における、検出値（同上）の各制御サイクルに対応する移動平均値の傾きが閾値未満である場合、当該電流検出器に異常が生じていると判定してもよい。また、制御装置１００は、電流の変化期間における、検出値（同上）を最小二乗法などで直線近似した直線の傾きが閾値未満である場合、当該電流検出器に異常が生じていると判定してもよい。同様の趣旨である限り、制御装置１００は、如何なる手法で電流検出器に異常が生じているか否かを判定してよい。閾値は、コンデンサ１１Ａの電圧と、前述したスイッチング部１１Ｃ－１、節点ｂ、遮断器１３、節点ａ、スイッチング部１１Ｃ－２、を順に経てコンデンサ１１Ａの負極に至る回路のインダクタンス（主にリアクトル１７による）から求められる電流の傾きの設計値に基づいて、予め計算され設定されている。電流検出器Ｓ３、Ｓ５、Ｓ２のそれぞれを判定の対象とする場合、それらに対する閾値は共通であってよい。 If the slope of the detected value of the current detector capable of detecting the current flowing through the commutation circuit 11 for each control cycle (rate of change with respect to the immediately preceding control cycle) during the current change period is less than the threshold, It is determined that an abnormality has occurred in the current detector. Alternatively, if the slope of the moving average value corresponding to each control cycle of the detected value (same as above) during the current change period is less than the threshold value, the control device 100 determines that an abnormality has occurred in the current detector. It may be determined that Further, the control device 100 determines that an abnormality has occurred in the current detector when the slope of a straight line obtained by linearly approximating the detected value (same as above) using the least squares method or the like during the current change period is less than a threshold value. It's okay. The control device 100 may use any method to determine whether or not an abnormality has occurred in the current detector, as long as the purpose is similar. The threshold value is determined by the voltage of the capacitor 11A and the inductance of the circuit (mainly the reactor 17 It is calculated and set in advance based on the design value of the current slope obtained from When each of the current detectors S3, S5, and S2 is to be subjected to determination, the threshold value for them may be common.

（判定処理Ａの第２例）
制御装置１００は、転流回路１１の状態をオフ状態からオン状態に、或いはオン状態からオフ状態に切り替えた前後における、転流回路１１を流れる電流を検出可能な電流検出器の検出値の変化度合いに基づいて、転流回路１１を流れる電流を検出可能な電流検出器に異常が生じているか否かを判定してもよい。「切り替えた前後における（中略）変化度合い」とは、例えば、転流回路１１の状態をオン状態にする直前の制御サイクルにおける検出値と、オン状態にすることによる電流変化が収束するのに十分な時間が経過した時点の制御サイクルにおける検出値との差分または変化率（いずれも絶対値）を意味する。転流回路１１をオン状態からオフ状態にする場合も同様である。以下、そのような意味であるものとして「切り替えた前後における変化度合い」なる語を用いて説明する。 (Second example of determination process A)
The control device 100 changes the detection value of a current detector capable of detecting the current flowing through the commutation circuit 11 before and after switching the state of the commutation circuit 11 from an off state to an on state or from an on state to an off state. Based on the degree, it may be determined whether an abnormality has occurred in a current detector capable of detecting the current flowing through the commutation circuit 11. "The degree of change before and after switching" refers to, for example, the detected value in the control cycle immediately before turning on the commutation circuit 11 and the current change sufficient to converge due to turning on the commutation circuit 11. It means the difference or rate of change (both absolute values) from the detected value in the control cycle after a certain period of time has elapsed. The same applies when switching the commutation circuit 11 from the on state to the off state. Hereinafter, the term "degree of change before and after switching" will be used to describe this meaning.

制御装置１００は、転流回路１１の状態を切り替えた前後における、転流回路１１を流れる電流を検出可能な電流検出器の検出値の変化度合いが閾値未満である場合、当該電流検出器に異常が生じていると判定する。閾値は、予め実験等により求められ設定されている。電流検出器Ｓ３、Ｓ５、Ｓ２のそれぞれを判定の対象とする場合、それらに対する閾値は共通であってよい。 If the degree of change in the detection value of a current detector capable of detecting the current flowing through the commutation circuit 11 before and after switching the state of the commutation circuit 11 is less than a threshold, the control device 100 detects an abnormality in the current detector. It is determined that this has occurred. The threshold value is determined and set in advance through experiments or the like. When each of the current detectors S3, S5, and S2 is to be subjected to determination, the threshold value for them may be common.

（判定処理Ａの拡張）
転流回路１１は、互いに直列に接続された複数の子転流回路を含んでもよい。図５は、変形例の直流電流遮断装置１Ａの構成の一例を示す図である。図示するように転流回路１１は、子転流回路１１－１、１１－２、…、１１－ｎを含む（ｎは２以上の自然数）。係る構成の場合、一部の子転流回路は遮断動作の際にオン状態にされず、待機状態のまま放置される場合がある。また、直流送電線の状況に応じて全ての子転流回路を、遮断動作の際にオン状態にする可能性もあるし、直流電流遮断装置１Ａの設置される環境に応じて一部の子転流回路のみオン状態にするか全ての子転流回路をオン状態にするかを切り替える場合もあり得る。すなわち、制御装置１００Ａは、遮断動作の際に、ｋ個（ｎ≧ｋ）の子転流回路をオン状態にする。そして、制御装置１００Ａは、判定処理Ａの第１例、第２例のいずれかを実行する場合において、転流回路１１を流れる電流を検出可能な電流検出器の検出値の変化度合い（電流の傾き、移動平均値または近似した直線の傾き、状態変化前後の変化度合い等）と、複数の子転流回路のうち状態を変更した子転流回路の数ｋに応じた閾値との比較に基づいて、転流回路を流れる電流を検出可能な電流検出器に異常が生じているか否かを判定する。この場合の閾値は、一つの子転流回路のみオン状態にする場合の閾値をＴｒｅｆとすると、Ｔｒｅｆ×ｋで求められる。 (Expansion of determination process A)
Commutation circuit 11 may include a plurality of child commutation circuits connected in series. FIG. 5 is a diagram showing an example of the configuration of a modified DC current interrupting device 1A. As illustrated, the commutation circuit 11 includes child commutation circuits 11-1, 11-2, . . . , 11-n (n is a natural number of 2 or more). In the case of such a configuration, some child commutation circuits may not be turned on during the interruption operation and may be left in a standby state. In addition, depending on the situation of the DC power transmission line, there is a possibility that all the child commutation circuits may be turned on during the interruption operation, or some of the child commutation circuits may be turned on depending on the environment in which the DC current interrupting device 1A is installed. There may also be a case where switching is made between turning on only the commutation circuit and turning on all child commutation circuits. That is, the control device 100A turns on k child commutation circuits (n≧k) during the cutoff operation. Then, when executing either the first example or the second example of the determination process A, the control device 100A determines the degree of change in the detected value of the current detector capable of detecting the current flowing through the commutation circuit 11 (current slope, moving average value or slope of an approximated straight line, degree of change before and after state change, etc.) and a threshold value corresponding to the number k of child commutation circuits whose state has changed among multiple child commutation circuits. Then, it is determined whether an abnormality has occurred in the current detector capable of detecting the current flowing through the commutation circuit. The threshold value in this case is determined by Tref×k, where Tref is the threshold value when only one child commutation circuit is turned on.

（判定処理Ｂの第１例）
制御装置１００は、半導体遮断器１４の状態をオフ状態からオン状態に、或いはオン状態からオフ状態に切り替えることで生じる、半導体遮断器１４を流れる電流の変化期間における、半導体遮断器１４を流れる電流を検出可能な電流検出器の検出値の変化度合いに基づいて、半導体遮断器１４を流れる電流を検出可能な電流検出器に異常が生じているか否かを判定する。例えば、半導体遮断器１４の状態をオフ状態からオン状態に切り替えた場合、一定期間の間、半導体遮断器１４を流れる電流は、制御サイクルの到来ごとに一定に近い傾き（変化率）で増加する。オン状態からオフ状態に切り替えた場合はその逆である。この状態が継続する時間は実験等で予め求められており、制御装置１００は、例えば半導体遮断器１４の状態を切り替えた時点を起点として、上記求められた時間よりも若干短い時間が経過する時点までを電流の変化期間として、上記の判定を行う。「半導体遮断器１４を流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ４である。電流検出器Ｓ４は、半導体遮断器１４とアレスタ１５が並列に接続されている部分の半導体遮断器１４側に設けられてもよい。制御装置１００は、判定処理Ａの第１例と同様に、半導体遮断器１４を流れる電流の変化期間における、電流検出器Ｓ４の検出値の変化度合い（電流の傾き、移動平均値または近似した直線の傾き等）が閾値未満である場合、電流検出器Ｓ４に異常が生じていると判定する。閾値は、判定処理Ａの第１例と同様に、コンデンサ１１Ａの電圧と、電流経路のインダクタンスに基づいて、予め計算され設定されている。 (First example of determination process B)
The control device 100 controls the current flowing through the semiconductor circuit breaker 14 during a period when the current flowing through the semiconductor circuit breaker 14 changes, which is caused by switching the state of the semiconductor circuit breaker 14 from an off state to an on state or from an on state to an off state. Based on the degree of change in the detected value of the current detector capable of detecting current, it is determined whether or not an abnormality has occurred in the current detector capable of detecting the current flowing through the semiconductor circuit breaker 14. For example, when the state of the semiconductor circuit breaker 14 is switched from the off state to the on state, the current flowing through the semiconductor circuit breaker 14 increases at a nearly constant slope (rate of change) every time a control cycle arrives for a certain period of time. . The opposite is true when switching from an on state to an off state. The time period during which this state lasts is determined in advance through experiments or the like, and the control device 100 starts from the point in time when the state of the semiconductor circuit breaker 14 is switched, for example, and controls the control device 100 at a point in time when a period of time slightly shorter than the determined time period has elapsed. The above determination is made with the period up to this period as the current change period. The "current detector capable of detecting the current flowing through the semiconductor circuit breaker 14" is, for example, the current detector S4. The current detector S4 may be provided on the semiconductor circuit breaker 14 side in a portion where the semiconductor circuit breaker 14 and the arrester 15 are connected in parallel. Similarly to the first example of determination processing A, the control device 100 determines the degree of change in the detected value of the current detector S4 (current slope, moving average value, or approximated straight line) during the change period of the current flowing through the semiconductor circuit breaker 14. slope, etc.) is less than the threshold value, it is determined that an abnormality has occurred in the current detector S4. As in the first example of determination processing A, the threshold value is calculated and set in advance based on the voltage of the capacitor 11A and the inductance of the current path.

（判定処理Ｂの第２例）
制御装置１００は、半導体遮断器１４の状態をオフ状態からオン状態に、或いはオン状態からオフ状態に切り替えた前後における、半導体遮断器１４を流れる電流を検出可能な電流検出器の検出値の変化度合いに基づいて、半導体遮断器１４を流れる電流を検出可能な電流検出器に異常が生じているか否かを判定してもよい。制御装置１００は、判定処理Ａの第２例と同様に、半導体遮断器１４の状態を切り替えた前後における、電流検出器Ｓ４の検出値の変化度合いが閾値未満である場合、電流検出器Ｓ４に異常が生じていると判定する。閾値は、判定処理Ａの第２例と同様に、予め実験等により求められ設定されている。 (Second example of determination process B)
The control device 100 changes the detection value of a current detector capable of detecting the current flowing through the semiconductor circuit breaker 14 before and after switching the state of the semiconductor circuit breaker 14 from an off state to an on state or from an on state to an off state. Based on the degree, it may be determined whether an abnormality has occurred in a current detector capable of detecting the current flowing through the semiconductor circuit breaker 14. Similarly to the second example of determination processing A, if the degree of change in the detected value of the current detector S4 before and after switching the state of the semiconductor circuit breaker 14 is less than the threshold, the control device 100 causes the current detector S4 to It is determined that an abnormality has occurred. As in the second example of determination processing A, the threshold value is determined and set in advance through experiments or the like.

（判定処理Ｃ）
制御装置１００は、断路器１２を流れる電流を検出可能な電流検出器の検出値および半導体遮断器１４を流れる電流を検出可能な電流検出器の検出値の和と、直流電流遮断装置１の全体に流れる電流を検出可能な電流検出器の検出値が一致しているか否かに基づいて、それらの電流検出器に異常が生じているか否かを判定する。「断路器１２を流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ１であり、「半導体遮断器１４を流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ４であり、「直流電流遮断装置１の全体に流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ６である。「一致している」とは、両者の差が種々の理由で生じ得る誤差の範囲内であることを含んでも良い。 (Judgment process C)
The control device 100 detects the sum of the detected value of the current detector capable of detecting the current flowing through the disconnector 12 and the detected value of the current detector capable of detecting the current flowing through the semiconductor circuit breaker 14, and the entire DC current interrupting device 1. Based on whether or not the detection values of the current detectors that can detect the current flowing in the current detectors match, it is determined whether or not an abnormality has occurred in the current detectors. The "current detector capable of detecting the current flowing through the disconnector 12" is, for example, the current detector S1, and the "current detector capable of detecting the current flowing through the semiconductor circuit breaker 14" is, for example, the current detector S1. The "current detector capable of detecting the current flowing throughout the DC current interrupting device 1" is, for example, the current detector S6. "Agreement" may include that the difference between the two is within the range of error that may occur for various reasons.

（判定処理Ｄ）
制御装置１００は、三以上の線路が接続される節点に接続された三以上の線路のそれぞれを流れる電流を検出可能な三以上の電流検出器の検出値がキルヒホッフの第１法則（節点に流れ込む電流と流出する電流の総和は等しい）を満たさない場合に、三以上の線路のそれぞれを流れる電流を検出可能な三以上の電流検出器のいずれかに異常が生じていると判定する。三以上の線路が接続される節点とは、例えば、節点ａであり、節点ａに接続された三以上の線路のそれぞれを流れる電流を検出可能な三以上の電流検出器は、電流検出器Ｓ１、Ｓ２、Ｓ３である。制御装置１００は、電流検出器Ｓ１の検出値と、電流検出器Ｓ２、Ｓ３の検出値の和とが一致しているか否かに基づいて、それらの電流検出器に異常が生じているか否かを判定する。また、三以上の線路が接続される節点とは、例えば、節点ｂであり、節点ｂに接続された三以上の線路のそれぞれを流れる電流を検出可能な三以上の電流検出器は、電流検出器Ｓ３、Ｓ４、Ｓ５である。制御装置１００は、電流検出器Ｓ３、Ｓ４の検出値の和と、電流検出器Ｓ５の検出値とが一致しているか否かに基づいて、それらの電流検出器に異常が生じているか否かを判定する。また、三以上の線路が接続される節点とは、例えば、節点ｃであり、節点ｃに接続された三以上の線路のそれぞれを流れる電流を検出可能な三以上の電流検出器は、電流検出器Ｓ２、Ｓ５、Ｓ６である。制御装置１００は、電流検出器Ｓ２、Ｓ５の検出値の和と、電流検出器Ｓ６の検出値とが一致しているか否かに基づいて、それらの電流検出器に異常が生じているか否かを判定する。 (Judgment process D)
The control device 100 is configured such that the detected values of three or more current detectors capable of detecting the current flowing through each of the three or more lines connected to the node where the three or more lines are connected are based on Kirchhoff's first law (flow into the node). (The sum of the current and the outgoing current is equal), it is determined that an abnormality has occurred in one of the three or more current detectors capable of detecting the current flowing through each of the three or more lines. The node to which three or more lines are connected is, for example, node a, and the three or more current detectors that can detect the current flowing through each of the three or more lines connected to node a are current detector S1. , S2, and S3. The control device 100 determines whether an abnormality has occurred in the current detectors based on whether the detected value of the current detector S1 and the sum of the detected values of the current detectors S2 and S3 match. Determine. Further, the node to which three or more lines are connected is, for example, node b, and three or more current detectors capable of detecting the current flowing through each of the three or more lines connected to node b are used for current detection. They are containers S3, S4, and S5. The control device 100 determines whether an abnormality has occurred in the current detectors based on whether the sum of the detected values of the current detectors S3 and S4 matches the detected value of the current detector S5. Determine. Further, a node to which three or more lines are connected is, for example, node c, and three or more current detectors capable of detecting current flowing through each of the three or more lines connected to node c are used for current detection. They are containers S2, S5, and S6. The control device 100 determines whether an abnormality has occurred in the current detectors based on whether the sum of the detected values of the current detectors S2 and S5 matches the detected value of the current detector S6. Determine.

（判定処理Ｅ）
制御装置１００は、上位制御装置２００から取得した直流電流遮断装置１の全体に流れる電流の値と、直流電流遮断装置１の全体に流れる電流を検出可能な電流検出器の検出値とを比較することで、直流電流遮断装置１の全体に流れる電流を検出可能な電流検出器に異常が生じているか否かを判定する。図６は、上位制御装置２００と制御装置１００との関係を示す図である。上位制御装置２００は、直流送電線ＤＬや直流電流遮断装置１などシステム全体の情報を統括する装置である。上位制御装置２００と制御装置１００はネットワークＮＷを介して通信する。ネットワークＮＷは、ＷＡＮ（Wide Area Network）やＬＡＮ（Local Area Network）、インターネット、公衆回線、光ファイバーや電気ケーブルによる直接接続等である。上位制御装置２００は、直流送電線ＤＬに流れる電流を検出する電流検出器２１０の検出値を取得し、これをネットワークＮＷを介して制御装置１００に伝送する。 (Judgment process E)
The control device 100 compares the value of the current flowing throughout the DC current interrupting device 1 obtained from the host control device 200 with the detection value of a current detector capable of detecting the current flowing throughout the DC current interrupting device 1. By doing so, it is determined whether or not an abnormality has occurred in the current detector capable of detecting the current flowing throughout the DC current interrupting device 1. FIG. 6 is a diagram showing the relationship between the higher-level control device 200 and the control device 100. The host control device 200 is a device that controls information about the entire system such as the DC power transmission line DL and the DC current interrupting device 1. Upper control device 200 and control device 100 communicate via network NW. The network NW is a WAN (Wide Area Network), a LAN (Local Area Network), the Internet, a public line, a direct connection using an optical fiber, an electric cable, or the like. The host control device 200 acquires the detection value of the current detector 210 that detects the current flowing through the DC power transmission line DL, and transmits this to the control device 100 via the network NW.

「直流電流遮断装置１の全体に流れる電流を検出可能な電流検出器」とは、例えば、電流検出器Ｓ６である。制御装置１００は、上位制御装置２００から取得した値と、電流検出器Ｓ６の検出値とが一致しない場合、電流検出器Ｓ６に異常が生じていると判定する。但し、上記の場合であっても、電流検出器Ｓ６の検出値が電流検出器Ｓ２、Ｓ５の検出値の和と一致している場合には、電流検出器２１０の方に異常が生じていると判定し、その旨を上位制御装置２００に送信してもよい。この場合、制御装置１００は、「一連の動作を停止する」ことを行わないようにしてもよいし、念のため行ってもよい。 The "current detector capable of detecting the current flowing throughout the DC current interrupting device 1" is, for example, the current detector S6. If the value acquired from the host control device 200 and the detected value of the current detector S6 do not match, the control device 100 determines that an abnormality has occurred in the current detector S6. However, even in the above case, if the detected value of the current detector S6 matches the sum of the detected values of the current detectors S2 and S5, an abnormality has occurred in the current detector 210. It may be determined that this is the case, and transmit that fact to the higher-level control device 200. In this case, the control device 100 may not "stop the series of operations" or may do so just in case.

図７は、遮断動作時において制御装置１００により実行される処理の流れの一例を示すフローチャートである。本フローチャートの処理は、例えば、遮断動作が開始されたタイミングで、遮断動作に係る処理と並行して実行される。 FIG. 7 is a flowchart showing an example of the flow of processing executed by the control device 100 during the shutoff operation. The processing in this flowchart is executed in parallel with the processing related to the cutoff operation, for example, at the timing when the cutoff operation is started.

まず、制御装置１００は、前述した判定処理Ｃ～Ｅを実行する（ステップＳ１００）。いずれかの判定処理において電流検出器に異常が生じていると判定した場合、制御装置１００は、直流電流を遮断するための一連の動作を停止し（ステップＳ１１４）、その旨を上位制御装置２００に通知する（ステップＳ１１６）。なお、ステップＳ１００の判定処理に関しては、遮断動作時以外にも行われてよいし、本フローチャートが実行されている間の任意のタイミングで行われてよい。遮断動作時以外に行われる場合、ステップＳ１１４の処理は省略されてよい。 First, the control device 100 executes the aforementioned determination processes C to E (step S100). If it is determined in any of the determination processes that an abnormality has occurred in the current detector, the control device 100 stops a series of operations for cutting off the DC current (step S114), and notifies the host control device 200 to that effect. (Step S116). Note that the determination process in step S100 may be performed at times other than the time of the shutoff operation, or may be performed at any timing while this flowchart is being executed. If the process is performed at a time other than the cutoff operation, the process of step S114 may be omitted.

判定処理Ｃ～Ｅの結果、電流検出器に異常が生じていないと判定した場合、制御装置１００は、転流回路１１がオフ状態からオン状態に変更されたか否かを判定する（ステップＳ１０２）。転流回路１１がオフ状態からオン状態に変更されると、制御装置１００は、判定処理Ａを実行する（ステップＳ１０４）。判定処理Ａにおいて電流検出器に異常が生じていると判定した場合、制御装置１００は、直流電流を遮断するための一連の動作を停止し（ステップＳ１１４）、その旨を上位制御装置２００に通知する（ステップＳ１１６）。 If it is determined that no abnormality has occurred in the current detector as a result of the determination processes C to E, the control device 100 determines whether the commutation circuit 11 has been changed from the off state to the on state (step S102). . When the commutation circuit 11 is changed from the off state to the on state, the control device 100 executes determination processing A (step S104). If it is determined in determination process A that an abnormality has occurred in the current detector, the control device 100 stops a series of operations for cutting off the DC current (step S114), and notifies the host control device 200 to that effect. (Step S116).

ステップＳ１０４の判定処理Ａの結果、電流検出器に異常が生じていないと判定した場合、制御装置１００は、転流回路１１がオン状態からオフ状態に変更されたか否かを判定する（ステップＳ１０６）。転流回路１１がオン状態からオフ状態に変更されると、制御装置１００は、再度判定処理Ａを実行する（ステップＳ１０８）。判定処理Ａにおいて電流検出器に異常が生じていると判定した場合、制御装置１００は、直流電流を遮断するための一連の動作を停止し（ステップＳ１１４）、その旨を上位制御装置２００に通知する（ステップＳ１１６）。 If it is determined that there is no abnormality in the current detector as a result of the determination process A in step S104, the control device 100 determines whether the commutation circuit 11 has been changed from the on state to the off state (step S106). ). When the commutation circuit 11 is changed from the on state to the off state, the control device 100 executes the determination process A again (step S108). If it is determined in determination process A that an abnormality has occurred in the current detector, the control device 100 stops a series of operations for cutting off the DC current (step S114), and notifies the host control device 200 to that effect. (Step S116).

ステップＳ１０８の判定処理Ａの結果、電流検出器に異常が生じていないと判定した場合、制御装置１００は、半導体遮断器１４がオフ状態からオン状態に変更されたか否かを判定する（ステップＳ１１０）。半導体遮断器１４がオフ状態からオン状態に変更されると、制御装置１００は、判定処理Ｂを実行する（ステップＳ１１２）。判定処理Ｂにおいて電流検出器に異常が生じていると判定した場合、制御装置１００は、直流電流を遮断するための一連の動作を停止し（ステップＳ１１４）、その旨を上位制御装置２００に通知する（ステップＳ１１６）。 If it is determined that there is no abnormality in the current detector as a result of the determination process A in step S108, the control device 100 determines whether the semiconductor circuit breaker 14 has been changed from the off state to the on state (step S110 ). When the semiconductor circuit breaker 14 is changed from the off state to the on state, the control device 100 executes determination processing B (step S112). If it is determined in determination process B that an abnormality has occurred in the current detector, the control device 100 stops a series of operations for cutting off the DC current (step S114), and notifies the host control device 200 to that effect. (Step S116).

以下、第１の実施形態の変形例について説明する。図８は、変形例に係る転流回路１１＃１の構成の一例を示す図である。転流回路１１＃１は、図１等に示したダイオード１１Ｂが混在したハーフブリッジ回路ではなく、ダイオード１１Ｂに代えてスイッチング部１１Ｃが設けられたフルブリッジ回路である。なお、図８においてはサイリスタ１１Ｄの図示を省略している。 Modifications of the first embodiment will be described below. FIG. 8 is a diagram showing an example of the configuration of a commutation circuit 11#1 according to a modification. The commutation circuit 11#1 is not a half-bridge circuit including the diode 11B shown in FIG. 1 etc., but a full-bridge circuit in which a switching section 11C is provided in place of the diode 11B. Note that in FIG. 8, illustration of the thyristor 11D is omitted.

また、半導体遮断器１４は、同様の回路を逆向きにも接続した双方向型であってもよい。また、遮断器１３や半導体遮断器１４を、直列に複数設けてもよい。また、補助断路器１８は省略されてもよい。 Moreover, the semiconductor circuit breaker 14 may be a bidirectional type in which similar circuits are connected in opposite directions. Further, a plurality of circuit breakers 13 and semiconductor circuit breakers 14 may be provided in series. Further, the auxiliary disconnector 18 may be omitted.

以上説明した第１の実施形態によれば、電流検出器の故障を早期に検出し、故障がある場合には速やかにシステムを保護停止させることができる。 According to the first embodiment described above, a failure of the current detector can be detected early, and if there is a failure, the system can be promptly brought to a protective stop.

（第２の実施形態）
以下、第２の実施形態について説明する。図９は、第２の実施形態に係る直流電流遮断装置１Ｂの構成の一例を示す図である。第１実施形態と共通する機能を有する構成要素については同一の符号を付している。図中の左側から右側に流れる電流を遮断する場合において、第２の実施形態の制御装置１００Ｂは、断路器１２を開極状態にしてアークが生じた状態で、転流回路１１＃１と半導体遮断器１４をオン状態にする。すると図中時計回りの電流が生じ、これがアークの電流を打ち消すように作用するため断路器１２に電流ゼロ点が生じ、断路器１２を電気的遮断状態にすることができる。その後で、制御装置１００Ｂは、半導体遮断器１４と転流回路１１＃１をオフ状態にすることで直流電流遮断装置１Ｂを流れる直流電流を遮断する。制御装置１００Ｂは、電流検出器Ｓ１２について判定処理Ａ、Ｂを行い、電流検出器Ｓ１１、Ｓ１２、Ｓ１３について判定処理Ｃ～Ｅを行うことができる。 (Second embodiment)
The second embodiment will be described below. FIG. 9 is a diagram showing an example of the configuration of a DC current interrupting device 1B according to the second embodiment. Components having functions common to those of the first embodiment are given the same reference numerals. In the case of interrupting the current flowing from the left side to the right side in the figure, the control device 100B of the second embodiment connects the commutation circuit 11#1 and the semiconductor with the disconnector 12 in an open state and an arc generated. Turn on the circuit breaker 14. Then, a current flows clockwise in the figure, and this acts to cancel the arc current, so that a current zero point occurs in the disconnector 12, and the disconnector 12 can be electrically cut off. After that, the control device 100B turns off the semiconductor circuit breaker 14 and the commutation circuit 11#1, thereby interrupting the DC current flowing through the DC current interrupting device 1B. The control device 100B can perform determination processes A and B for the current detector S12, and can perform determination processes C to E for the current detectors S11, S12, and S13.

（第３の実施形態）
以下、第３の実施形態について説明する。図１０は、第３の実施形態に係る直流電流遮断装置１Ｃの構成の一例を示す図である。第１実施形態と共通する機能を有する構成要素については同一の符号を付している。第３の実施形態の直流電流遮断装置１Ｃは、転流回路１１＃２を備える。転流回路１１＃２は、スイッチング素子とダイオードが逆並列に設けられたスイッチングが、逆向きで直列に接続されたものである。転流回路１１＃２は、通常送電時においてオン状態に維持される。図中の左側から右側に流れる電流を遮断する場合において、第３の実施形態の制御装置１００Ｃは、断路器１２を開極状態にしてアークが生じた状態で、半導体遮断器１４をオン状態にした上で、転流回路１１＃２のスイッチング部のいずれかまたは双方をオフ状態にする。すると電流は半導体遮断器１４に転流する。その後で、制御装置１００Ｃは、半導体遮断器１４をオフ状態にすることで直流電流遮断装置１Ｃを流れる直流電流を遮断する。第３の実施形態の制御装置１００Ｃは、電流検出器Ｓ２２について判定処理Ａ、Ｂを行い、電流検出器Ｓ２１、Ｓ２２、Ｓ２３について判定処理Ｃ～Ｅを行うことができる。 (Third embodiment)
The third embodiment will be described below. FIG. 10 is a diagram showing an example of the configuration of a DC current interrupting device 1C according to the third embodiment. Components having functions common to those of the first embodiment are given the same reference numerals. The DC current interrupting device 1C of the third embodiment includes a commutation circuit 11#2. The commutation circuit 11#2 is a circuit in which switching elements and diodes are provided in antiparallel and connected in series in opposite directions. The commutation circuit 11#2 is maintained in the on state during normal power transmission. In the case of interrupting the current flowing from the left side to the right side in the figure, the control device 100C of the third embodiment turns on the semiconductor circuit breaker 14 while the disconnector 12 is in the open state and an arc is generated. Then, one or both of the switching sections of the commutation circuit 11#2 is turned off. The current then commutates to the semiconductor circuit breaker 14. After that, the control device 100C turns off the semiconductor circuit breaker 14, thereby interrupting the DC current flowing through the DC current interrupting device 1C. The control device 100C of the third embodiment can perform determination processes A and B for the current detector S22, and can perform determination processes C to E for the current detectors S21, S22, and S23.

以上説明した少なくともひとつの実施形態によれば、機械式接点または電気式接点（１２）と、機械式接点または電気式接点と並行に設けられた半導体遮断器（１４）と、機械式接点または電気式接点を流れる電流を半導体遮断器に転流させる転流回路（１１、１１＃１、１１＃２）と、複数の電流検出器（Ｓ１～Ｓ６、Ｓ１１～Ｓ１３、Ｓ２１～Ｓ２３）と、複数の電流検出器の検出値に基づいて機械式接点または電気式接点、半導体遮断器、および転流回路を制御し、直流電流遮断装置（１、１Ａ、１Ｂ、１Ｃ）を流れる直流電流を遮断する制御装置（１００、１００Ａ、１００Ｂ、１００Ｃ）と、を備え、制御装置は、複数の電流検出器のうち一部または全部の電流検出器の検出値の変化度合いまたは、他の電流検出器の検出値との関係に基づいて複数の電流検出器のうち一部または全部に異常が生じているか否かを判定し、異常が生じていると判定した場合、直流電流を遮断するための一連の動作を停止することにより、電流検出器の故障を早期に検出し、故障がある場合には速やかにシステムを保護停止させることができる。 According to at least one embodiment described above, the mechanical contact or the electrical contact (12), the semiconductor circuit breaker (14) provided in parallel with the mechanical contact or the electrical contact, and the mechanical contact or the electrical contact A commutation circuit (11, 11#1, 11#2) that commutates the current flowing through the type contact to the semiconductor circuit breaker, a plurality of current detectors (S1 to S6, S11 to S13, S21 to S23), and a plurality of Controls mechanical contacts or electrical contacts, semiconductor circuit breakers, and commutation circuits based on the detected value of the current detector, and interrupts the direct current flowing through the direct current interrupting device (1, 1A, 1B, 1C). A control device (100, 100A, 100B, 100C), the control device controls the degree of change in the detected value of some or all of the plurality of current detectors or the detection of other current detectors. A series of actions to determine whether an abnormality has occurred in some or all of the multiple current detectors based on the relationship with the value, and if it is determined that an abnormality has occurred, to cut off the DC current. By stopping the current detector, failure of the current detector can be detected early, and if a failure occurs, the system can be immediately brought to a protective stop.

本発明のいくつかの実施形態を説明したが、これらの実施形態は、例として提示したものであり、発明の範囲を限定することは意図していない。これら実施形態は、その他の様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で、種々の省略、置き換え、変更を行うことができる。これら実施形態やその変形は、発明の範囲や要旨に含まれると同様に、特許請求の範囲に記載された発明とその均等の範囲に含まれるものである。 Although several embodiments of the invention have been described, these embodiments are 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, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention as well as within the scope of the invention described in the claims and its equivalents.

１、１Ａ、１Ｂ、１Ｃ直流電流遮断装置
１１、１１＃１、１１＃２転流回路
１１Ａコンデンサ
１１Ｂダイオード
１１Ｃスイッチング部
１１Ｄサイリスタ
１２断路器
１３遮断器
１４半導体遮断器
１５アレスタ
１６ダイオード
１７リアクトル
１００、１００Ａ、１００Ｂ、１００Ｃ制御装置
ＤＬ直流送電線 1, 1A, 1B, 1C DC current interrupting device 11, 11#1, 11#2 Commutation circuit 11A Capacitor 11B Diode 11C Switching section 11D Thyristor 12 Disconnector 13 Circuit breaker 14 Semiconductor circuit breaker 15 Arrester 16 Diode 17 Reactor 100, 100A, 100B, 100C Control device DL DC power transmission line

Claims

mechanical or electrical contacts;
a semiconductor circuit breaker provided in parallel with the mechanical contact or the electrical contact;
a commutation circuit that commutates the current flowing through the mechanical contact or the electrical contact to the semiconductor circuit breaker;
multiple current detectors;
a control device that controls the mechanical contacts or electrical contacts, the semiconductor circuit breaker, and the commutation circuit based on the detected values of the plurality of current detectors, and interrupts the direct current flowing through the direct current interrupting device; Equipped with
The control device controls the control of the plurality of current detectors based on the degree of change in the detected values of some or all of the plurality of current detectors or the relationship with the detected values of other current detectors. determining whether an abnormality has occurred in some or all of them, and if it is determined that an abnormality has occurred, stopping a series of operations for interrupting the direct current;
DC current interrupter.

The plurality of current detectors include a current detector capable of detecting a current flowing through the commutation circuit,
The control device controls the degree of change in the detection value of a current detector capable of detecting the current flowing through the commutation circuit during a period of change in the current flowing through the commutation circuit, which is caused by switching the state of the commutation circuit. Based on the above, determining whether an abnormality has occurred in a current detector capable of detecting the current flowing through the commutation circuit,
The direct current interrupting device according to claim 1.

The plurality of current detectors include a current detector capable of detecting a current flowing through the commutation circuit,
The control device detects the current flowing through the commutation circuit based on the degree of change in the detection value of a current detector capable of detecting the current flowing through the commutation circuit before and after switching the state of the commutation circuit. Determine whether an abnormality has occurred in the possible current detector,
The direct current interrupting device according to claim 1 or 2.

The commutation circuit includes a plurality of child commutation circuits connected in series with each other,
The control device controls the current flowing through the commutation circuit based on a comparison between the degree of change in the detected value and a threshold value corresponding to the number of child commutation circuits whose states have been changed among the plurality of child commutation circuits. Determine whether there is an abnormality in the current detector that can detect the
The direct current interrupting device according to claim 2 or 3.

The plurality of current detectors include a current detector capable of detecting a current flowing through the semiconductor circuit breaker,
The control device controls the degree of change in the detection value of a current detector capable of detecting the current flowing through the semiconductor circuit breaker during a period of change in the current flowing through the semiconductor circuit breaker caused by switching the state of the semiconductor circuit breaker. Based on the above, it is determined whether an abnormality has occurred in a current detector capable of detecting the current flowing through the semiconductor circuit breaker.
The direct current interrupting device according to any one of claims 1 to 4.

The plurality of current detectors include a current detector capable of detecting a current flowing through the semiconductor circuit breaker,
The control device detects the current flowing through the semiconductor circuit breaker based on the degree of change in a detected value of a current detector capable of detecting the current flowing through the semiconductor circuit breaker before and after switching the state of the semiconductor circuit breaker. Determine whether an abnormality has occurred in the possible current detector,
The direct current interrupting device according to any one of claims 1 to 5.

The plurality of current detectors include a current detector capable of detecting the current flowing through the mechanical contact or the electrical contact, a current detector capable of detecting the current flowing through the semiconductor circuit breaker, and a current detector capable of detecting the current flowing through the semiconductor circuit breaker. and a current detector capable of detecting the current flowing throughout the
The control device calculates the sum of the detection value of a current detector capable of detecting the current flowing through the mechanical contact or the electrical contact and the detection value of the current detector capable of detecting the current flowing through the semiconductor circuit breaker, and the direct current. A current detector capable of detecting the current flowing through the mechanical contact or the electrical contact based on whether detected values of the current detector capable of detecting the current flowing throughout the current interrupting device match or not; determining whether an abnormality has occurred in a current detector capable of detecting the current flowing through the circuit breaker or a current detector capable of detecting the current flowing throughout the DC current interrupting device;
A direct current interrupting device according to any one of claims 1 to 6.

The plurality of current detectors include three or more current detectors capable of detecting current flowing through each of the three or more lines connected to a node to which three or more lines are connected,
The control device detects the current flowing through each of the three or more lines when the detected values of the three or more current detectors that can detect the current flowing through each of the three or more lines do not satisfy Kirchhoff's first law. It is determined that an abnormality has occurred in one of three or more current detectors capable of detecting
A direct current interrupting device according to any one of claims 1 to 7.

The plurality of current detectors include a current detector capable of detecting a current flowing throughout the DC current interrupting device,
The control device communicates with a higher-level control device that instructs a series of operations for interrupting the DC current, and transmits the value of the current flowing throughout the DC current interrupting device acquired from the higher-level control device and the DC current. By comparing the detection value of the current detector capable of detecting the current flowing throughout the entire DC current interrupting device, it can be determined whether or not an abnormality has occurred in the current detector capable of detecting the current flowing throughout the DC current interrupting device. judge,
A direct current interrupting device according to any one of claims 1 to 7.

The plurality of current detectors further include a current detector capable of detecting the current flowing through the mechanical contact or the electrical contact, and a current detector capable of detecting the current flowing through the semiconductor circuit breaker,
The control device is configured such that the value of the current flowing throughout the DC current interrupting device obtained from the host control device is different from the value detected by a current detector capable of detecting the current flowing throughout the DC current interrupting device. , and the sum of a detection value of a current detector capable of detecting the current flowing through the mechanical contact or the electrical contact and a detection value of a current detector capable of detecting the current flowing through the semiconductor circuit breaker, and the DC current interruption. If the detection values of the current detectors capable of detecting the current flowing through the entire device match, the above-mentioned controller determines that the value of the current flowing through the entire DC current interrupting device obtained from the higher-level control device is abnormal. Notify the upper control device,
The direct current interrupting device according to claim 9.

The commutation circuit includes one or more switching elements,
The control device turns off all gate signals applied to the commutation circuit and the semiconductor circuit breaker when stopping the series of operations for interrupting the direct current.
The direct current interrupting device according to any one of claims 1 to 10.

The control device includes:
communicating with a higher-level control device that instructs a series of operations to interrupt the direct current;
When stopping the series of operations for cutting off the DC current, transmitting information to the higher-level control device that an abnormality has occurred in some or all of the plurality of current detectors;
The direct current interrupting device according to any one of claims 1 to 11.