JP2024080351A - Anomaly detection device - Google Patents

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JP2024080351A
JP2024080351A JP2022193476A JP2022193476A JP2024080351A JP 2024080351 A JP2024080351 A JP 2024080351A JP 2022193476 A JP2022193476 A JP 2022193476A JP 2022193476 A JP2022193476 A JP 2022193476A JP 2024080351 A JP2024080351 A JP 2024080351A
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亮 小林
彰大 大堀
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Daihen Corp
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Abstract

【課題】三相配線の接続異常を検出する際に、処理時間の変動を抑制できる異常検出装置を提供する。【解決手段】異常検出装置Ａ１において、三相配線の三相交流に基づく相電圧信号Ｖｕ，Ｖｖ，Ｖｗをα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換する三相二相変換部２１と、α軸電圧信号Ｖαに含まれる正相分の信号である正相分信号Ｖα’と、β軸電圧信号Ｖβに含まれる正相分の信号である正相分信号Ｖβ’とを、それぞれ抽出する正相分抽出部２２と、α軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに基づいて実効値Ｖを算出する実効値算出部２３と、正相分信号Ｖα’，Ｖβ’に基づいて、実効値Ｖ’を算出する実効値算出部２４と、実効値Ｖおよび実効値Ｖ’に基づく逆相割合ｋを算出する逆相割合算出部２５と、逆相割合ｋと所定の閾値ｋ0とを比較することで、三相配線の接続異常を判定する判定部２６とを備えた。【選択図】図１[Problem] To provide an abnormality detection device capable of suppressing fluctuations in processing time when detecting a connection abnormality in three-phase wiring. [Solution] An abnormality detection device A1 includes a three-phase to two-phase conversion unit 21 that converts phase voltage signals Vu, Vv, Vw based on three-phase AC of the three-phase wiring into an α-axis voltage signal Vα and a β-axis voltage signal Vβ, a positive-phase component extraction unit 22 that extracts a positive-phase component signal Vα' that is a positive-phase component signal included in the α-axis voltage signal Vα and a positive-phase component signal Vβ' that is a positive-phase component signal included in the β-axis voltage signal Vβ, an effective value calculation unit 23 that calculates an effective value V based on the α-axis voltage signal Vα and the β-axis voltage signal Vβ, an effective value calculation unit 24 that calculates the effective value V' based on the positive-phase component signals Vα' and Vβ', a negative-phase ratio calculation unit 25 that calculates a negative-phase ratio k based on the effective value V and the effective value V', and a determination unit 26 that determines a connection abnormality in the three-phase wiring by comparing the negative-phase ratio k with a predetermined threshold value k0. [Selected Figure] FIG.

Description

本発明は、三相配線の接続異常を検出する異常検出装置に関する。 The present invention relates to an anomaly detection device that detects connection anomalies in three-phase wiring.

例えばパワーコンディショナの交流出力または交流モータの入力などの三相配線を外部の三相配線に接続する場合、相順を誤って逆相に接続してしまう場合がある。逆相で接続された場合、機器が正しく動作しなかったり、故障してしまうおそれがある。これを防止するために、逆相接続を検出する方法が開発されている。例えば、基準相の電圧のゼロクロスを検出して、その時の判定相の電圧の極性によって、正相接続であるか逆相接続であるかを判定する方法がある。例えば、特許文献１には、基準相の電圧の一方の半サイクルの立ち上がりが検出されたときに、判定相の電圧の一方の半サイクルの有無によって、相回転の方向を判定する判定手段を備えた相回転検出装置が開示されている。 For example, when connecting three-phase wiring such as the AC output of a power conditioner or the input of an AC motor to external three-phase wiring, the phase sequence may be mistakenly connected in reverse. If the device is connected in reverse phase, it may not operate correctly or may break down. To prevent this, methods for detecting reverse phase connection have been developed. For example, there is a method of detecting the zero crossing of the reference phase voltage and determining whether the connection is positive phase or negative phase depending on the polarity of the voltage of the determination phase at that time. For example, Patent Document 1 discloses a phase rotation detection device equipped with a determination means for determining the direction of phase rotation depending on the presence or absence of one half cycle of the voltage of the determination phase when the rising edge of one half cycle of the reference phase voltage is detected.

実開平１－１８０６７０号公報Japanese Utility Model Application Publication No. 1-180670 特開２０１３－０８３５６６号公報JP 2013-083566 A 特開２０１３－１０１０１６号公報JP 2013-101016 A

しかしながら、上記のような判定方法の場合、ゼロクロスを検出するために、基準相の現在の電圧情報以外に過去の電圧情報を記憶する必要がある。また、ゼロクロスのタイミングのときだけ処理内容が変わって、ソフトウエアの処理時間が延びるという問題がある。組み込みマイコンを利用する場合、演算速度の関係で、タイミングによって処理時間が異なることはできるだけ避けたいという事情がある。 However, when using the above judgment method, in order to detect zero crossings, it is necessary to store past voltage information in addition to the current voltage information of the reference phase. Also, there is a problem that the processing content changes only at the timing of zero crossings, which increases the software processing time. When using an embedded microcontroller, it is desirable to avoid differences in processing time depending on the timing as much as possible due to the calculation speed.

本発明は上述した事情のもとで考え出されたものであって、三相配線の接続異常を検出する際に、処理時間の変動を抑制できる異常検出装置を提供することをその目的としている。 The present invention was conceived in light of the above circumstances, and its purpose is to provide an anomaly detection device that can suppress fluctuations in processing time when detecting connection anomalies in three-phase wiring.

上記課題を解決するため、本発明では、次の技術的手段を講じている。 To solve the above problems, the present invention provides the following technical solutions:

本発明の第１の側面によって提供される異常検出装置は、三相配線の三相交流に基づく３個の信号を第１の信号および第２の信号に変換する三相二相変換部と、前記第１の信号に含まれる正相分の信号である第１の正相分信号と、前記第２の信号に含まれる正相分の信号である第２の正相分信号とを、それぞれ抽出する正相分抽出部と、前記第１の信号および前記第２の信号に基づいて、第１実効値を算出する第１実効値算出部と、前記第１の正相分信号および前記第２の正相分信号に基づいて、第２実効値を算出する第２実効値算出部と、前記第１実効値および前記第２実効値に基づく割合を算出する割合算出部と、前記割合と所定の閾値とを比較することで、前記三相配線の接続異常を判定する判定部と、を備えている。なお、「正相分の信号」とは、三相交流の基本波と周波数が同じで相順が同じ信号であり、「逆相分の信号」とは、三相交流の基本波と周波数が同じで相順が逆の信号である。 The abnormality detection device provided by the first aspect of the present invention includes a three-phase to two-phase conversion unit that converts three signals based on three-phase AC of three-phase wiring into a first signal and a second signal, a positive-phase component extraction unit that extracts a first positive-phase component signal that is a positive-phase component signal included in the first signal and a second positive-phase component signal that is a positive-phase component signal included in the second signal, respectively, a first effective value calculation unit that calculates a first effective value based on the first signal and the second signal, a second effective value calculation unit that calculates a second effective value based on the first positive-phase component signal and the second positive-phase component signal, a ratio calculation unit that calculates a ratio based on the first effective value and the second effective value, and a determination unit that determines a connection abnormality of the three-phase wiring by comparing the ratio with a predetermined threshold value. Note that the "positive-phase component signal" is a signal that has the same frequency and phase sequence as the fundamental wave of the three-phase AC, and the "negative-phase component signal" is a signal that has the same frequency and phase sequence as the fundamental wave of the three-phase AC.

本発明の好ましい実施の形態においては、前記割合算出部は、前記第１実効値に対する、前記第１実効値から前記第２実効値を減じた差の割合を算出する。 In a preferred embodiment of the present invention, the ratio calculation unit calculates the ratio of the difference between the first effective value and the second effective value.

本発明の好ましい実施の形態においては、前記閾値は、６０％より大きく、１００％より小さい。 In a preferred embodiment of the present invention, the threshold is greater than 60% and less than 100%.

本発明の好ましい実施の形態においては、前記正相分抽出部は、複数の帯域通過型の複素係数フィルタと、帯域阻止型の複素係数フィルタとを用いて、前記第１の正相分信号および前記第２の正相分信号を抽出する。 In a preferred embodiment of the present invention, the positive-phase-sequence component extraction unit extracts the first positive-phase-sequence component signal and the second positive-phase-sequence component signal using a plurality of band-pass complex-coefficient filters and a band-rejection complex-coefficient filter.

本発明の第２の側面によって提供される異常検出装置は、三相配線の三相交流に基づく３個の信号を第１の信号および第２の信号に変換する三相二相変換部と、前記第１の信号に含まれる正相分の信号である第１の正相分信号と、前記第２の信号に含まれる正相分の信号である第２の正相分信号とを、それぞれ抽出する正相分抽出部と、前記第１の正相分信号および前記第２の正相分信号に基づいて、正相分実効値を算出する正相分実効値算出部と、前記第１の信号に含まれる逆相分の信号である第１の逆相分信号と、前記第２の信号に含まれる逆相分の信号である第２の逆相分信号とを、それぞれ抽出する逆相分抽出部と、前記第１の逆相分信号および前記第２の逆相分信号に基づいて、逆相分実効値を算出する逆相分実効値算出部と、前記正相分実効値と前記逆相分実効値とから不平衡率を算出する不平衡率算出部と、前記不平衡率と所定の閾値とを比較することで、前記三相配線の接続異常を判定する判定部と、を備えている。 The abnormality detection device provided by the second aspect of the present invention includes a three-phase to two-phase conversion unit that converts three signals based on three-phase AC of a three-phase wiring into a first signal and a second signal, a positive-phase component extraction unit that extracts a first positive-phase component signal that is a positive-phase component signal included in the first signal and a second positive-phase component signal that is a positive-phase component signal included in the second signal, respectively, a positive-phase component effective value calculation unit that calculates a positive-phase component effective value based on the first positive-phase component signal and the second positive-phase component signal, and The system includes a negative-phase-sequence component extraction unit that extracts a first negative-phase-sequence component signal, which is a negative-phase-sequence component signal included in the second signal, and a second negative-phase-sequence component signal, which is a negative-phase-sequence component signal included in the second signal; a negative-phase-sequence component effective value calculation unit that calculates a negative-phase-sequence component effective value based on the first negative-phase-sequence component signal and the second negative-phase-sequence component signal; an unbalance ratio calculation unit that calculates an unbalance ratio from the positive-phase-sequence component effective value and the negative-phase-sequence component effective value; and a determination unit that determines a connection abnormality in the three-phase wiring by comparing the unbalance ratio with a predetermined threshold value.

本発明によると、第１の信号および第２の信号に基づいて第１実効値が算出され、正相分を抽出した第１の正相分信号および第２の正相分信号に基づいて第２実効値が算出される。そして、第１実効値および第２実効値に基づく割合を閾値と比較することで接続異常が判定される。したがって、本発明にかかる異常検出装置は、三相配線の接続異常を検出できる。また、いずれのタイミングにおいても、実施される処理は共通している。したがって、本発明にかかる異常検出装置は、処理時間の変動を抑制できる。 According to the present invention, a first effective value is calculated based on a first signal and a second signal, and a second effective value is calculated based on a first positive-phase component signal and a second positive-phase component signal from which the positive-phase component is extracted. Then, a connection abnormality is determined by comparing a ratio based on the first effective value and the second effective value with a threshold value. Therefore, the abnormality detection device according to the present invention can detect a connection abnormality in three-phase wiring. Furthermore, the processing performed at each timing is the same. Therefore, the abnormality detection device according to the present invention can suppress fluctuations in processing time.

本発明のその他の特徴および利点は、添付図面を参照して以下に行う詳細な説明によって、より明らかとなろう。 Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

第１実施形態に係る異常検出装置を説明するためのブロック図である。1 is a block diagram for explaining an abnormality detection device according to a first embodiment. 判定部における逆相割合の閾値を設定するためのシミュレーション結果を説明するための図である。13 is a diagram for explaining a simulation result for setting a threshold value of the reverse phase ratio in the determination unit. FIG. 第１実施形態に係る異常検出装置が行う接続異常検出処理を説明するためのフローチャートの一例である。5 is an example of a flowchart for explaining a connection abnormality detection process performed by the abnormality detection device according to the first embodiment. 第２実施形態に係る異常検出装置の全体構成を示すブロック図である。FIG. 11 is a block diagram showing the overall configuration of an abnormality detection device according to a second embodiment.

以下、本発明の実施の形態を、図面を参照して具体的に説明する。 The following describes in detail the embodiment of the present invention with reference to the drawings.

図１（ａ）は、第１実施形態に係る異常検出装置Ａ１の全体構成を示すブロック図である。図１（ｂ）は、異常検出装置Ａ１の正相分抽出部２２の内部構成の一例を示すブロック図である。 Figure 1(a) is a block diagram showing the overall configuration of an abnormality detection device A1 according to the first embodiment. Figure 1(b) is a block diagram showing an example of the internal configuration of a positive-phase component extraction unit 22 of the abnormality detection device A1.

異常検出装置Ａ１は、三相配線の接続異常を検出する装置であり、例えばパワーコンディショナまたは交流モータなどの、三相交流を利用する各種機器に配置される。電圧センサ４は、三相配線の各相電圧を検出するものであり、Ｕ相の相電圧を検出した相電圧信号Ｖｕ、Ｖ相の相電圧を検出した相電圧信号Ｖｖ、Ｗ相の相電圧を検出した相電圧信号Ｖｗを異常検出装置Ａ１に出力する。異常検出装置Ａ１は、電圧センサ４より入力される相電圧信号Ｖｕ，Ｖｖ，Ｖｗに基づいて接続異常を検出する。 The abnormality detection device A1 is a device that detects connection abnormalities in three-phase wiring, and is placed in various devices that use three-phase AC, such as a power conditioner or an AC motor. The voltage sensor 4 detects each phase voltage of the three-phase wiring, and outputs a phase voltage signal Vu that detects the phase voltage of the U phase, a phase voltage signal Vv that detects the phase voltage of the V phase, and a phase voltage signal Vw that detects the phase voltage of the W phase to the abnormality detection device A1. The abnormality detection device A1 detects connection abnormalities based on the phase voltage signals Vu, Vv, and Vw input from the voltage sensor 4.

異常検出装置Ａ１は、図１（ａ）に示すように、演算部２および表示部３を備えている。演算部２は、逆相割合ｋを演算し、逆相割合ｋに基づいて接続異常であるか否かを判定する構成であり、例えばマイクロコンピュータなどによって実現されている。逆相割合ｋは、三相配線の電圧のうち、正相分の電圧を除いた電圧の割合を、百分率で示している。一般的に、三相配線の電圧には、正相分の電圧以外に、逆相分の電圧、および、高調波成分の電圧などが含まれている。本明細書では、三相配線の電圧のうち、正相分の電圧を除いた電圧（逆相分の電圧、および、高調波成分の電圧などを合わせた合計電圧）の割合を、「逆相割合」と記載する。演算部２は、判定結果を表示部３に出力する。表示部３は、判定結果を表示する構成であり、モニタなどの表示手段によって実現されている。表示部３は、演算部２より入力された判定結果を表示する。また、演算部２は、接続が適切であると判定した場合、異常検出装置Ａ１が配置された機器に起動を許可する信号を送信する。一方、演算部２が接続異常であると判定した場合、当該機器に起動を許可する信号が送信されないので、当該機器は起動しない。演算部２は、三相二相変換部２１、正相分抽出部２２、実効値算出部２３，２４、逆相割合算出部２５、および判定部２６を備えている。 As shown in FIG. 1(a), the abnormality detection device A1 includes a calculation unit 2 and a display unit 3. The calculation unit 2 is configured to calculate the negative phase ratio k and determine whether or not there is a connection abnormality based on the negative phase ratio k, and is realized by, for example, a microcomputer. The negative phase ratio k indicates the ratio of the voltage of the three-phase wiring excluding the positive phase voltage, expressed as a percentage. In general, the voltage of the three-phase wiring includes, in addition to the positive phase voltage, the negative phase voltage and the voltage of the harmonic components. In this specification, the ratio of the voltage of the three-phase wiring excluding the positive phase voltage (the total voltage including the negative phase voltage and the voltage of the harmonic components) is described as the "negative phase ratio". The calculation unit 2 outputs the judgment result to the display unit 3. The display unit 3 is configured to display the judgment result, and is realized by a display means such as a monitor. The display unit 3 displays the judgment result input from the calculation unit 2. Furthermore, if the calculation unit 2 determines that the connection is appropriate, it transmits a signal to the device in which the abnormality detection device A1 is located to allow it to start up. On the other hand, if the calculation unit 2 determines that there is an abnormal connection, the signal to allow the device to start up is not transmitted to the device, and the device does not start up. The calculation unit 2 includes a three-phase to two-phase conversion unit 21, a positive-phase component extraction unit 22, effective value calculation units 23 and 24, a negative-phase ratio calculation unit 25, and a determination unit 26.

三相二相変換部２１は、電圧センサ４より入力される３個の相電圧信号Ｖｕ，Ｖｖ，Ｖｗを、α軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換する。三相二相変換部２１は、いわゆる三相二相変換処理（αβ変換処理）を行うものであり、相電圧信号Ｖｕ，Ｖｖ，Ｖｗを互いに直交するα軸成分とβ軸成分とにそれぞれ分解して、各軸成分をまとめることでα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβを生成する。三相二相変換部２１は、α軸電圧信号Ｖαおよびβ軸電圧信号Ｖβを、正相分抽出部２２および実効値算出部２３に出力する。 The three-phase to two-phase conversion unit 21 converts the three phase voltage signals Vu, Vv, and Vw input from the voltage sensor 4 into an α-axis voltage signal Vα and a β-axis voltage signal Vβ. The three-phase to two-phase conversion unit 21 performs so-called three-phase to two-phase conversion processing (αβ conversion processing), and decomposes the phase voltage signals Vu, Vv, and Vw into mutually orthogonal α-axis and β-axis components, respectively, and generates the α-axis voltage signal Vα and the β-axis voltage signal Vβ by combining the respective axis components. The three-phase to two-phase conversion unit 21 outputs the α-axis voltage signal Vα and the β-axis voltage signal Vβ to the positive-phase component extraction unit 22 and the effective value calculation unit 23.

正相分抽出部２２は、三相二相変換部２１より入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβから、基本波（例えば６０Ｈｚ）の正相分信号Ｖα’，Ｖβ’を抽出する。抽出された正相分信号Ｖα’，Ｖβ’は、実効値算出部２４に出力される。正相分抽出部２２は、複素係数フィルタを備えており、本実施形態では、図１（ｂ）に示すように、複数の複素係数バンドパスフィルタ（帯域通過型の複素係数フィルタ）２２１と、１個の複素係数ノッチフィルタ（帯域阻止型の複素係数フィルタ）２２２と、を備えている。 The positive-phase-sequence extraction unit 22 extracts positive-phase-sequence signals Vα', Vβ' of a fundamental wave (e.g., 60 Hz) from the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. The extracted positive-phase-sequence signals Vα', Vβ' are output to the effective value calculation unit 24. The positive-phase-sequence extraction unit 22 includes a complex coefficient filter, and in this embodiment, as shown in FIG. 1(b), includes a plurality of complex coefficient band-pass filters (complex coefficient filters of band-pass type) 221 and one complex coefficient notch filter (complex coefficient filter of band-rejection type) 222.

複素係数バンドパスフィルタ２２１は、例えば複素係数の１次ＩＩＲフィルタで構成されている。複素係数バンドパスフィルタ２２１の通過帯域を決定する正規化角周波数Ωdとして、系統電圧の基本波（正相分）の角周波数ω0（例えば、ω0＝１２０π[rad/sec]（６０[Ｈｚ]））を正規化したωdがあらかじめ設定されている。複素係数バンドパスフィルタ２２１は、その他の角周波数の信号（逆相分および高調波成分）を好適に除去して、基本波の正相分の信号を通過させる。本実施形態では、正相分抽出部２２が３個の複素係数バンドパスフィルタ２２１を備えている例を示しているが、正相分抽出部２２が備える複素係数バンドパスフィルタ２２１の数は限定されない。正相分抽出部２２は、複素係数バンドパスフィルタ２２１の数が多いほど、より精度よく、基本波の正相分の信号を通過させられる。なお、複素係数バンドパスフィルタ２２１は、上記に限定されず、例えば複素係数の２次以上のＩＩＲフィルタなどで構成されてもよい。 The complex coefficient bandpass filter 221 is configured, for example, by a complex coefficient first-order IIR filter. As the normalized angular frequency Ωd that determines the passband of the complex coefficient bandpass filter 221, ωd, which is obtained by normalizing the angular frequency ω0 (for example, ω0 = 120π [rad/sec] (60 [Hz])) of the fundamental wave (positive phase component) of the system voltage, is set in advance. The complex coefficient bandpass filter 221 preferably removes signals of other angular frequencies (negative phase components and harmonic components) and passes the positive phase component signal of the fundamental wave. In this embodiment, an example is shown in which the positive phase component extraction unit 22 has three complex coefficient bandpass filters 221, but the number of complex coefficient bandpass filters 221 that the positive phase component extraction unit 22 has is not limited. The more complex coefficient bandpass filters 221 are provided, the more accurately the positive phase component signal of the fundamental wave can be passed by the positive phase component extraction unit 22. Note that the complex coefficient bandpass filter 221 is not limited to the above, and may be configured, for example, as a complex coefficient second-order or higher IIR filter.

複素係数ノッチフィルタ２２２は、例えば複素係数の１次ＩＩＲフィルタで構成されている。複素係数ノッチフィルタ２２２の阻止帯域を決定する正規化角周波数Ωdとして、系統電圧の基本波（逆相分）の角周波数「－ω0」（－６０[Ｈｚ]）を正規化した「－ωd」があらかじめ設定されている。複素係数ノッチフィルタ２２２は、基本波の逆相分の信号の通過を抑制することで、基本波の正相分の信号を抽出する。本実施形態では、正相分抽出部２２が１個の複素係数ノッチフィルタ２２２を備えている例を示しているが、正相分抽出部２２が備える複素係数ノッチフィルタ２２２の数は限定されない。正相分抽出部２２は、複素係数ノッチフィルタ２２２の数が多いほど、より精度よく、基本波の正相分の信号を抽出できる。なお、複素係数ノッチフィルタ２２２は、上記に限定されず、例えば複素係数の２次以上のＩＩＲフィルタなどで構成されてもよい。 The complex coefficient notch filter 222 is configured, for example, by a complex coefficient first-order IIR filter. The normalized angular frequency Ωd that determines the stop band of the complex coefficient notch filter 222 is set in advance to "-ωd", which is the normalized angular frequency "-ω0" (-60 [Hz]) of the fundamental wave (negative phase component) of the system voltage. The complex coefficient notch filter 222 extracts the positive phase component signal of the fundamental wave by suppressing the passage of the negative phase component signal of the fundamental wave. In this embodiment, an example is shown in which the positive phase component extraction unit 22 has one complex coefficient notch filter 222, but the number of complex coefficient notch filters 222 that the positive phase component extraction unit 22 has is not limited. The more complex coefficient notch filters 222 are provided, the more accurately the positive phase component extraction unit 22 can extract the positive phase component signal of the fundamental wave. Note that the complex coefficient notch filter 222 is not limited to the above, and may be configured, for example, by a complex coefficient second-order or higher IIR filter.

なお、正相分抽出部２２は、複素係数バンドパスフィルタ２２１のみで構成されてもよい。また、正相分抽出部２２は、複素係数ノッチフィルタ２２２と、例えば５次、７次、１１次高調波（正相分）を抑制するための各複素係数ノッチフィルタとで構成されてもよい。正相分抽出部２２は、基本波の正相分の信号を通過させ、その他の信号を抑制できる複素係数フィルタであればよい。正相分抽出部２２を構成する複素係数フィルタの詳細な例は、例えば特許文献２に開示されている。 The positive-phase-sequence extraction unit 22 may be composed of only the complex-coefficient band-pass filter 221. The positive-phase-sequence extraction unit 22 may also be composed of the complex-coefficient notch filter 222 and complex-coefficient notch filters for suppressing, for example, the fifth, seventh, and eleventh harmonics (positive phase components). The positive-phase-sequence extraction unit 22 may be any complex-coefficient filter that can pass the positive-phase signal of the fundamental wave and suppress other signals. A detailed example of the complex-coefficient filter constituting the positive-phase-sequence extraction unit 22 is disclosed in, for example, Patent Document 2.

実効値算出部２３は、三相二相変換部２１から入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに基づいて、三相配線の電圧の実効値Ｖを算出する。具体的には、実効値算出部２３は、α軸電圧信号Ｖαを２乗した値とβ軸電圧信号Ｖβを２乗した値との加算値の平方根を、実効値Ｖ（＝√（Ｖα2＋Ｖβ2））として算出する。実効値算出部２３は、算出した実効値Ｖを逆相割合算出部２５に出力する。 The effective value calculation unit 23 calculates the effective value V of the voltage of the three-phase wiring based on the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. Specifically, the effective value calculation unit 23 calculates the square root of the sum of the squared value of the α-axis voltage signal Vα and the squared value of the β-axis voltage signal Vβ as the effective value V (=√(Vα 2 + Vβ 2 )). The effective value calculation unit 23 outputs the calculated effective value V to the negative phase ratio calculation unit 25.

実効値算出部２４は、正相分抽出部２２から入力される正相分信号Ｖα’および正相分信号Ｖβ’に基づいて、三相配線の電圧から正相分を抽出した電圧の実効値Ｖ’を算出する。具体的には、実効値算出部２４は、正相分信号Ｖα’を２乗した値と正相分信号Ｖβ’を２乗した値との加算値の平方根に（５／３）を乗算した値を、実効値Ｖ’（＝（５／３）・√（Ｖα’2＋Ｖβ’2））として算出する。正相分抽出部２２から出力される正相分信号Ｖα’および正相分信号Ｖβ’は、正相分抽出部２２のフィルタの特性により、（３／５）に減衰しているので、減衰前の値にするために（５／３）を乗算している。実効値算出部２４は、算出した実効値Ｖ’を逆相割合算出部２５に出力する。 The effective value calculation unit 24 calculates an effective value V' of a voltage obtained by extracting a positive phase component from the voltage of the three-phase wiring based on the positive phase component signal Vα' and the positive phase component signal Vβ' input from the positive phase component extraction unit 22. Specifically, the effective value calculation unit 24 calculates the effective value V'(=(5/3)·√(Vα' 2 +Vβ' 2 )) by multiplying the square root of the sum of the squared value of the positive phase component signal Vα' and the squared value of the positive phase component signal Vβ' by ( 5/3 ). The positive phase component signal Vα' and the positive phase component signal Vβ' output from the positive phase component extraction unit 22 are attenuated to (3/5) due to the characteristics of the filter of the positive phase component extraction unit 22, so that they are multiplied by (5/3) to return them to values before attenuation. The effective value calculation unit 24 outputs the calculated effective value V' to the negative phase ratio calculation unit 25.

逆相割合算出部２５は、実効値算出部２３から入力される実効値Ｖと、実効値算出部２４から入力される実効値Ｖ’とから、逆相割合ｋを算出する。具体的には、逆相割合算出部２５は、実効値Ｖから実効値Ｖ’を減算した値を、実効値Ｖで除算し、１００を乗算した値を、逆相割合ｋ（＝（Ｖ－Ｖ’）・１００／Ｖ）として算出する。逆相割合算出部２５ は、算出した逆相割合ｋを判定部２６ に出力する。 The negative-phase-sequence ratio calculation unit 25 calculates the negative-phase-sequence ratio k from the effective value V input from the effective value calculation unit 23 and the effective value V' input from the effective value calculation unit 24. Specifically, the negative-phase-sequence ratio calculation unit 25 subtracts the effective value V' from the effective value V, divides the result by the effective value V, and multiplies the result by 100 to calculate the negative-phase-sequence ratio k (=(V-V') x 100/V). The negative-phase-sequence ratio calculation unit 25 outputs the calculated negative-phase-sequence ratio k to the determination unit 26.

三相配線が正しい相順で接続され、三相配線の電圧が正相分だけで構成された理想的な状態であった場合、正相分抽出部２２の入力側と出力側とで信号に変化がなく、実効値Ｖと実効値Ｖ’とが等しくなる。この場合、逆相割合ｋは０％になる。しかし、実際には、三相配線が正しい相順で接続されている場合でも、三相配線の電圧には、正相分の電圧以外に、逆相分の電圧、および、高調波成分の電圧などが含まれている。したがって、正相分抽出部２２の出力側の正相分が抽出された信号は入力側の信号より小さくなるので、実効値Ｖ’は実効値Ｖより小さくなる。よって、逆相割合ｋは０％より大きな値になる。一方、三相配線が逆相の相順で接続されていると、三相配線の電圧には正相分の電圧がほとんど含まれないので、正相分抽出部２２の出力側の信号の実効値Ｖ’が「０」に近い値になる。この場合、逆相割合ｋは１００％に近い値になる。 In an ideal state in which the three-phase wiring is connected in the correct phase sequence and the voltage of the three-phase wiring is composed of only the positive phase components, there is no change in the signal between the input side and the output side of the positive phase component extraction unit 22, and the effective value V and the effective value V' are equal. In this case, the negative phase ratio k is 0%. However, in reality, even if the three-phase wiring is connected in the correct phase sequence, the voltage of the three-phase wiring contains not only the positive phase component voltage, but also the negative phase component voltage and the voltage of the harmonic components. Therefore, the signal from which the positive phase component is extracted on the output side of the positive phase component extraction unit 22 is smaller than the signal on the input side, so the effective value V' is smaller than the effective value V. Therefore, the negative phase ratio k is a value larger than 0%. On the other hand, if the three-phase wiring is connected in the reverse phase sequence, the voltage of the three-phase wiring contains almost no positive phase component voltage, so the effective value V' of the signal on the output side of the positive phase component extraction unit 22 is close to "0". In this case, the negative phase ratio k is close to 100%.

判定部２６は、逆相割合算出部２５が算出した逆相割合ｋを入力され、逆相割合ｋとあらかじめ設定されている所定の閾値ｋ0とを比較することで、三相配線の接続異常であるか否かを判定する。閾値ｋ0は、三相配線の接続異常を判定できる値があらかじめ設定される。上述したように、逆相割合ｋは、三相配線が逆相の相順で接続されている場合は１００％に近い値になる。一方、三相配線が正しい相順で接続されている場合、逆相割合ｋは、０％より大きな値になり、三相配線の電圧に含まれる、正相分以外の成分の大きさに応じて大きくなる。閾値ｋ0は、三相配線が正しい相順で接続された場合に、ある程度の高調波が含まれていても、接続異常と判定されない値が設定される。また、系統連系規定の事故時運転継続（FRT：Fault Ride Through）要件において、太陽光発電設備は、二相短絡事故による電圧低下時でも運転の継続が求められている。したがって、閾値ｋ0は、二相短絡事故が発生した場合でも、接続異常と判定されない値である必要がある。これらを踏まえて、閾値ｋ0は、シミュレーションなどに基づいて適宜設定される。 The determination unit 26 receives the negative phase ratio k calculated by the negative phase ratio calculation unit 25, and compares the negative phase ratio k with a preset threshold value k 0 to determine whether or not the connection of the three-phase wiring is abnormal. The threshold value k 0 is preset to a value that can determine the connection abnormality of the three-phase wiring. As described above, the negative phase ratio k is close to 100% when the three-phase wiring is connected in a reverse phase sequence. On the other hand, when the three-phase wiring is connected in a correct phase sequence, the negative phase ratio k is a value greater than 0% and increases according to the magnitude of the components other than the positive phase components contained in the voltage of the three-phase wiring. The threshold value k 0 is set to a value that is not determined to be a connection abnormality even if a certain amount of harmonics is included when the three-phase wiring is connected in a correct phase sequence. In addition, in the Fault Ride Through (FRT) requirement of the grid interconnection regulations, the photovoltaic power generation facility is required to continue operation even when the voltage drops due to a two-phase short circuit accident. Therefore, the threshold value k 0 needs to be a value that is not determined to be a connection abnormality even when a two-phase short circuit accident occurs. Taking these factors into consideration, the threshold value k 0 is appropriately set based on simulations or the like.

図２は、閾値ｋ0を設定するためのシミュレーション結果を説明するための図である。図１に示す異常検出装置Ａ１において、電圧センサ４が配置された三相配線に様々な三相交流電圧を印加して逆相割合ｋを検出するシミュレーションを行った。図２に示す各図は、逆相割合算出部２５が算出した逆相割合ｋの時間変化を示しており、各図の横軸は時間を示し、縦軸は逆相割合ｋを示している。 Fig. 2 is a diagram for explaining the results of a simulation for setting the threshold value k0 . In the abnormality detection device A1 shown in Fig. 1, a simulation was performed to detect the negative-phase-sequence ratio k by applying various three-phase AC voltages to the three-phase wiring in which the voltage sensor 4 is arranged. Each diagram shown in Fig. 2 shows the time change of the negative-phase-sequence ratio k calculated by the negative-phase-sequence ratio calculation unit 25, with the horizontal axis of each diagram indicating time and the vertical axis indicating the negative-phase-sequence ratio k.

図２（ａ）は、三相配線に理想的な正相分だけの三相交流電圧を印加した場合を示している。この場合、正相分抽出部２２の入力側と出力側とで信号に変化がないので、逆相割合ｋは０％になっている。図２（ｂ）は、三相配線に逆相分だけの三相交流電圧を印加した場合を示している。この場合、正相分抽出部２２の出力側の信号の実効値Ｖ’が「０」になるので、逆相割合ｋは１００％になっている。 Figure 2(a) shows the case where an ideal three-phase AC voltage of only the positive sequence component is applied to the three-phase wiring. In this case, since there is no change in the signal between the input side and the output side of the positive sequence component extraction unit 22, the negative sequence ratio k is 0%. Figure 2(b) shows the case where an ideal three-phase AC voltage of only the negative sequence component is applied to the three-phase wiring. In this case, since the effective value V' of the signal on the output side of the positive sequence component extraction unit 22 is "0", the negative sequence ratio k is 100%.

図２（ｃ）は、正相分の三相交流電圧に５次、７次、１１次の各高調波を５％ずつ重畳した三相交流電圧を、三相配線に印加した場合を示している。５次、７次、１１次の各高調波は、三相配線で一般的に発生する高調波である。また、５％は、十分に大きい水準である。この場合、高調波の影響で、逆相割合ｋには、周期的な変動が生じている。逆相割合ｋの最大値は１５％程度である。図２（ｄ）は、逆相分の三相交流電圧に５次、７次、１１次の各高調波を５％ずつ重畳した三相交流電圧を、三相配線に印加した場合を示している。この場合、高調波による影響は現れず、逆相割合ｋは、図２（ｂ）と同様に、１００％になっている。 Figure 2(c) shows a case where a three-phase AC voltage in which 5th, 7th, and 11th harmonics are superimposed by 5% each on the positive-phase three-phase AC voltage is applied to a three-phase wiring. The fifth, seventh, and 11th harmonics are harmonics that generally occur in three-phase wiring. 5% is a sufficiently large level. In this case, the negative-phase ratio k fluctuates periodically due to the influence of the harmonics. The maximum value of the negative-phase ratio k is about 15%. Figure 2(d) shows a case where a three-phase AC voltage in which 5th, 7th, and 11th harmonics are superimposed by 5% each on the negative-phase three-phase AC voltage is applied to a three-phase wiring. In this case, there is no influence of the harmonics, and the negative-phase ratio k is 100%, as in Figure 2(b).

図２（ｅ）は、Ｙ結線側の系統で二相短絡事故が発生したときのＹ結線側での正相分の三相交流電圧を、三相配線に印加した場合を示している。この場合、逆相割合ｋには、周期的な変動が生じている。逆相割合ｋの最大値は５０％程度である。なお、図示しないが、Δ結線側での三相交流電圧を印加した場合の逆相割合ｋの時間変化は、図２（ｅ）と同様であった。 Figure 2(e) shows the case where a positive-phase three-phase AC voltage on the Y-connection side is applied to the three-phase wiring when a two-phase short circuit fault occurs in the system on the Y-connection side. In this case, the negative-phase ratio k fluctuates periodically. The maximum value of the negative-phase ratio k is about 50%. Although not shown, the change over time of the negative-phase ratio k when a three-phase AC voltage is applied on the Δ-connection side is the same as in Figure 2(e).

図２（ｆ）は、Ｙ結線側の系統で二相短絡事故が発生したときのＹ結線側での正相分の三相交流電圧に５次、７次、１１次の各高調波を５％ずつ重畳した三相交流電圧を、三相配線に印加した場合を示している。この場合、逆相割合ｋには、周期的な変動が生じている。逆相割合ｋの最大値は６０％である。なお、図示しないが、Δ結線側での三相交流電圧（５次、７次、１１次の各高調波を５％ずつ重畳）を印加した場合の逆相割合ｋの時間変化は、図２（ｆ）と同様であった。図２（ｆ）に示すシミュレーションにおいて、逆相割合ｋが最大（６０％）になることが判った。したがって、閾値ｋ0は、６０％より大きく、１００％より小さい値を設定するのが望ましく、さらに上下に余裕をもって、７０％より大きく、９０％より小さい値を設定するのがより望ましい。本実施形態では、閾値ｋ0として８０％が設定されている。なお、閾値ｋ0は、これに限定されない。 FIG. 2(f) shows a case where a three-phase AC voltage in which 5th, 7th, and 11th harmonics are superimposed at 5% each on the positive-phase three-phase AC voltage on the Y-connection side when a two-phase short circuit accident occurs in the system on the Y-connection side is applied to the three-phase wiring. In this case, a periodic fluctuation occurs in the negative phase ratio k. The maximum value of the negative phase ratio k is 60%. Although not shown, the time change of the negative phase ratio k when a three-phase AC voltage (5th, 7th, and 11th harmonics are superimposed at 5% each) on the Δ-connection side is the same as that in FIG. 2(f). In the simulation shown in FIG. 2(f), it was found that the negative phase ratio k becomes maximum (60%). Therefore, it is preferable to set the threshold value k 0 to a value larger than 60% and smaller than 100%, and more preferably to set a value larger than 70% and smaller than 90% with a margin above and below. In this embodiment, 80% is set as the threshold value k 0. It is to be noted that the threshold value k 0 is not limited to this.

判定部２６は、逆相割合ｋが閾値ｋ0以上の状態が所定時間Ｔ0以上経過した場合に接続異常であると判定し、それ以外の場合には正常であると判定する。所定時間Ｔ0は、逆相割合ｋが瞬間的に閾値ｋ0以上となった場合に誤検出してしまうことを防止するために設けられており、例えば数秒程度である。なお、所定時間Ｔ0は限定されない。また、所定時間Ｔ0は設定されなくてもよく、判定部２６は、逆相割合ｋが閾値ｋ0以上である場合に、接続異常であると判定してもよい。判定部２６が判定した判定結果は、表示部３に出力されて表示される。 The determination unit 26 determines that a connection abnormality has occurred when the state in which the negative phase ratio k is equal to or greater than the threshold value k0 has continued for a predetermined time T0 or more, and otherwise determines that the connection is normal. The predetermined time T0 is provided to prevent erroneous detection when the negative phase ratio k momentarily becomes equal to or greater than the threshold value k0 , and is, for example, about several seconds. Note that the predetermined time T0 is not limited. Also, the predetermined time T0 does not need to be set, and the determination unit 26 may determine that a connection abnormality has occurred when the negative phase ratio k is equal to or greater than the threshold value k0 . The determination result determined by the determination unit 26 is output to the display unit 3 and displayed.

図３は、異常検出装置Ａ１が行う接続異常検出処理を説明するためのフローチャートの一例である。当該接続異常検出処理は、異常検出装置Ａ１が配置された機器の起動時に実施される。 Figure 3 is an example of a flowchart for explaining the connection abnormality detection process performed by the abnormality detection device A1. The connection abnormality detection process is performed when the device in which the abnormality detection device A1 is installed is started up.

まず、時間を計時するための変数である経過時間Ｔを「０」に初期化する（Ｓ１）。次に、三相配線の電圧の実効値Ｖが算出される（Ｓ２）。具体的には、実効値算出部２３が、三相二相変換部２１から入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに基づいて、実効値Ｖ（＝√（Ｖα2＋Ｖβ2））を算出する。次に、正相分を抽出した電圧の実効値Ｖ’が算出される（Ｓ３）。具体的には、実効値算出部２４が、正相分抽出部２２から入力される正相分信号Ｖα’および正相分信号Ｖβ’に基づいて、実効値Ｖ’（＝（５／３）・√（Ｖα’2＋Ｖβ’2））を算出する。次に、逆相割合ｋが算出される（Ｓ４）。具体的には、逆相割合算出部２５が、実効値Ｖと実効値Ｖ’とから、逆相割合ｋ（＝（Ｖ－Ｖ’）・１００／Ｖ）を算出する。なお、図２に示すように、逆相割合ｋは電圧の測定開始直後には適切な値にならない場合があるので、定常状態になってから（図２の例では０．０２秒程度経過してから）、接続異常検出処理が開始される。 First, the elapsed time T, which is a variable for counting time, is initialized to "0" (S1). Next, the effective value V of the voltage of the three-phase wiring is calculated (S2). Specifically, the effective value calculation unit 23 calculates the effective value V (=√(Vα 2 +Vβ 2 )) based on the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. Next, the effective value V' of the voltage from which the positive phase component is extracted is calculated (S3). Specifically, the effective value calculation unit 24 calculates the effective value V'(=(5/3)√(Vα' 2 +Vβ' 2 )) based on the positive phase component signal Vα' and the positive phase component signal Vβ' input from the positive phase component extraction unit 22. Next, the negative phase ratio k is calculated (S4). Specifically, the negative-phase-sequence ratio calculation unit 25 calculates the negative-phase-sequence ratio k (=(V-V')·100/V) from the effective values V and V'. As shown in Fig. 2, the negative-phase-sequence ratio k may not be an appropriate value immediately after the start of voltage measurement, so the connection abnormality detection process is started after a steady state is reached (after about 0.02 seconds have elapsed in the example of Fig. 2).

次に、逆相割合ｋが閾値ｋ0以上であるか否かが判別される（Ｓ５）。逆相割合ｋが閾値ｋ0以上である場合（Ｓ５：ＹＥＳ）、経過時間Ｔを増加させて（Ｓ６）、経過時間Ｔが所定時間Ｔ0以上であるか否かが判別される（Ｓ７）。経過時間Ｔが所定時間Ｔ0未満である場合（Ｓ７：ＮＯ）、ステップＳ２に戻って、ステップＳ２～Ｓ７の処理が繰り返される。 Next, it is determined whether the negative phase ratio k is equal to or greater than a threshold value k0 (S5). If the negative phase ratio k is equal to or greater than the threshold value k0 (S5: YES), the elapsed time T is increased (S6), and it is determined whether the elapsed time T is equal to or greater than a predetermined time T0 (S7). If the elapsed time T is less than the predetermined time T0 (S7: NO), the process returns to step S2, and steps S2 to S7 are repeated.

ステップＳ５において、逆相割合ｋが閾値ｋ0未満である場合（Ｓ５：ＮＯ）、接続が適切であると判断され、適切に接続されている旨が表示部３に表示され（Ｓ８）、異常検出装置Ａ１が配置された機器に起動を許可する信号が送信されて（Ｓ９）、接続異常検出処理は終了する。一方、ステップＳ７において、経過時間Ｔが所定時間Ｔ0以上である場合（Ｓ７：ＹＥＳ）、接続異常であると判断され、接続異常である旨が表示部３に表示され（Ｓ１０）、接続異常検出処理は終了する。この場合、異常検出装置Ａ１が配置された機器に起動を許可する信号は送信されないので、当該機器は起動しない。なお、異常検出装置Ａ１が行う接続異常検出処理は、図３に示すフローチャートに限定されない。 In step S5, if the reverse phase ratio k is less than the threshold value k0 (S5: NO), the connection is judged to be appropriate, a message indicating that the connection is appropriate is displayed on the display unit 3 (S8), a signal permitting startup is sent to the device in which the abnormality detection device A1 is installed (S9), and the connection abnormality detection process ends. On the other hand, in step S7, if the elapsed time T is equal to or greater than the predetermined time T0 (S7: YES), the connection is judged to be abnormal, a message indicating that the connection is abnormal is displayed on the display unit 3 (S10), and the connection abnormality detection process ends. In this case, a signal permitting startup is not sent to the device in which the abnormality detection device A1 is installed, so the device does not start up. Note that the connection abnormality detection process performed by the abnormality detection device A1 is not limited to the flowchart shown in FIG. 3.

次に、異常検出装置Ａ１の作用効果について説明する。 Next, we will explain the effects of the abnormality detection device A1.

本実施形態によると、逆相割合算出部２５が実効値Ｖと実効値Ｖ’とから逆相割合ｋを算出し、判定部２６が逆相割合ｋと所定の閾値ｋ0とを比較することで、三相配線の接続異常を判定する。これにより、異常検出装置Ａ１は、三相配線の接続異常を検出できる。また、異常検出装置Ａ１は、接続異常の検出においてゼロクロスタイミングを利用しないので、いずれのタイミングにおいても、実施される処理は共通している。したがって、異常検出装置Ａ１は、処理時間の変動を抑制できる。 According to this embodiment, the negative phase ratio calculation unit 25 calculates the negative phase ratio k from the effective value V and the effective value V', and the determination unit 26 compares the negative phase ratio k with a predetermined threshold value k0 to determine a connection abnormality in the three-phase wiring. In this way, the abnormality detection device A1 can detect a connection abnormality in the three-phase wiring. Furthermore, since the abnormality detection device A1 does not use zero crossing timing in detecting a connection abnormality, the processing performed is the same at any timing. Therefore, the abnormality detection device A1 can suppress fluctuations in processing time.

また、本実施形態によると、三相二相変換部２１は、電圧センサ４より入力される３個の相電圧信号Ｖｕ，Ｖｖ，Ｖｗを、α軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換する。正相分抽出部２２は、三相二相変換部２１より入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβから、基本波の正相分信号Ｖα’，Ｖβ’を抽出する。実効値算出部２３は、三相二相変換部２１から入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに基づいて、三相配線の電圧の実効値Ｖを算出する。実効値算出部２４は、正相分抽出部２２から入力される正相分信号Ｖα’，Ｖβ’に基づいて、三相配線の電圧から正相分を抽出した電圧の実効値Ｖ’を算出する。逆相割合算出部２５は、実効値Ｖと実効値Ｖ’とから逆相割合ｋを算出する。このように、異常検出装置Ａ１は、簡単な演算処理で逆相割合ｋを検出できる。 In addition, according to this embodiment, the three-phase to two-phase conversion unit 21 converts the three phase voltage signals Vu, Vv, and Vw input from the voltage sensor 4 into an α-axis voltage signal Vα and a β-axis voltage signal Vβ. The positive-phase component extraction unit 22 extracts the positive-phase component signals Vα' and Vβ' of the fundamental wave from the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. The effective value calculation unit 23 calculates the effective value V of the voltage of the three-phase wiring based on the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. The effective value calculation unit 24 calculates the effective value V' of the voltage obtained by extracting the positive phase component from the voltage of the three-phase wiring based on the positive-phase component signals Vα' and Vβ' input from the positive-phase component extraction unit 22. The negative-phase ratio calculation unit 25 calculates the negative-phase ratio k from the effective value V and the effective value V'. In this way, the abnormality detection device A1 can detect the negative phase ratio k with simple calculation processing.

また、本実施形態によると、判定部２６が逆相割合ｋと比較するための閾値ｋ0を、６０％より大きく１００％より小さい値に設定する。したがって、異常検出装置Ａ１は、三相配線の接続異常を適切に検出できる。 According to the present embodiment, the threshold value k0 for comparison with the negative phase ratio k by the determination unit 26 is set to a value greater than 60% and less than 100%. Therefore, the abnormality detection device A1 can appropriately detect a connection abnormality in the three-phase wiring.

また、本実施形態によると、正相分抽出部２２は、複数の複素係数バンドパスフィルタ（帯域通過型の複素係数フィルタ）２２１と、１個の複素係数ノッチフィルタ（帯域阻止型の複素係数フィルタ）２２２とを備えている。したがって、正相分抽出部２２は、精度よく、基本波の正相分の信号を抽出できる。 In addition, according to this embodiment, the positive-phase component extraction unit 22 includes a plurality of complex-coefficient band-pass filters (complex-coefficient band-pass filters) 221 and one complex-coefficient notch filter (complex-coefficient band-rejection filter) 222. Therefore, the positive-phase component extraction unit 22 can extract the positive-phase component signal of the fundamental wave with high accuracy.

なお、本実施形態では、演算部２が逆相割合ｋを算出する場合について説明したが、これに限られない。演算部２は、逆相割合算出部２５の代わりに、正相割合算出部を備えて、正相割合ｋ’を算出してもよい。正相割合ｋ’は、三相配線の電圧のうちの正相分の電圧の割合を百分率で示している。正相割合算出部は、実効値算出部２４から入力される実効値Ｖ’を、実効値算出部２３から入力される実効値Ｖで除算し、１００を乗算した値を、正相割合ｋ’（＝Ｖ’・１００／Ｖ）として算出する。 In this embodiment, the calculation unit 2 calculates the negative phase ratio k, but this is not limited to the above. The calculation unit 2 may be provided with a positive phase ratio calculation unit instead of the negative phase ratio calculation unit 25 to calculate the positive phase ratio k'. The positive phase ratio k' indicates the ratio of the positive phase voltage to the voltage of the three-phase wiring as a percentage. The positive phase ratio calculation unit divides the effective value V' input from the effective value calculation unit 24 by the effective value V input from the effective value calculation unit 23, and multiplies the result by 100 to calculate the positive phase ratio k' (= V' 100/V).

上述のように、三相配線が正しい相順で接続され、三相配線の電圧が正相分だけで構成された理想的な状態であった場合、実効値Ｖと実効値Ｖ’とが等しくなる。この場合、正相割合ｋ’は１００％になる。しかし、実際には、三相配線が正しい相順で接続されている場合でも、三相配線の電圧には正相分以外の電圧が含まれているので、実効値Ｖ’は実効値Ｖより小さくなる。よって、正相割合ｋ’は１００％より小さい値になる。一方、三相配線が逆相の相順で接続されていると、三相配線の電圧には正相分の電圧がほとんど含まれないので、正相分抽出部２２の出力側の信号の実効値Ｖ’が「０」に近い値になる。この場合、正相割合ｋ’は０％に近い値になる。 As described above, in an ideal state in which the three-phase wiring is connected in the correct phase sequence and the voltage of the three-phase wiring is composed only of positive phase components, the effective value V and the effective value V' are equal. In this case, the positive phase ratio k' is 100%. However, in reality, even if the three-phase wiring is connected in the correct phase sequence, the voltage of the three-phase wiring contains voltages other than the positive phase components, so the effective value V' is smaller than the effective value V. Therefore, the positive phase ratio k' is a value smaller than 100%. On the other hand, if the three-phase wiring is connected in the reverse phase sequence, the voltage of the three-phase wiring contains almost no positive phase voltage, so the effective value V' of the signal on the output side of the positive phase extraction unit 22 is close to "0". In this case, the positive phase ratio k' is close to 0%.

判定部２６は、正相割合算出部が算出した正相割合ｋ’とあらかじめ設定されている所定の閾値ｋ’0とを比較することで、三相配線の接続異常であるか否かを判定する。閾値ｋ’0は、三相配線の接続異常を判定できる値が、シミュレーションなどに基づいて適宜設定される。図２と同様のシミュレーションを行った結果、図２（ｆ）と同じ三相交流電圧を三相配線に印加した場合に、正相割合ｋ’の最小値が４０％になった。したがって、閾値ｋ’0は、４０％より小さく、０％より大きい値を設定するのが望ましく、さらに上下に余裕をもって、３０％より小さく、１０％より大きい値を設定するのがより望ましい。閾値ｋ’0は、例えば２０％が設定されるが、これに限定されない。 The determination unit 26 compares the positive phase ratio k' calculated by the positive phase ratio calculation unit with a predetermined threshold value k'0 set in advance to determine whether or not there is a connection abnormality in the three-phase wiring. The threshold value k'0 is appropriately set based on a simulation or the like, so that a value that can determine a connection abnormality in the three-phase wiring can be determined. As a result of performing a simulation similar to that of FIG. 2, when the same three-phase AC voltage as that of FIG. 2(f) is applied to the three-phase wiring, the minimum value of the positive phase ratio k' becomes 40%. Therefore, it is preferable to set the threshold value k'0 to a value smaller than 40% and larger than 0%, and more preferably to set a value smaller than 30% and larger than 10% with a margin above and below. The threshold value k'0 is set to, for example, 20%, but is not limited to this.

また、本実施形態では、正相分抽出部２２が複素係数フィルタを備えている場合について説明したが、これに限られない。正相分抽出部２２は、基本波の正相分の信号を通過させ、その他の信号を抑制できるフィルタであればよい。例えば特許文献３には、回転座標変換処理（ｄｑ変換処理）を改良した線形時不変の処理（ＤＱ－ＬＴＩ変換処理）を利用したローパスフィルタまたはハイパスフィルタを用いる正相分抽出部２２の例が開示されている。 In addition, in this embodiment, the positive-phase-sequence extraction unit 22 is described as having a complex coefficient filter, but this is not limited to this. The positive-phase-sequence extraction unit 22 may be any filter that can pass the positive-phase signal of the fundamental wave and suppress other signals. For example, Patent Document 3 discloses an example of a positive-phase-sequence extraction unit 22 that uses a low-pass filter or a high-pass filter that utilizes a linear time-invariant process (DQ-LTI conversion process) that is an improvement of the rotating coordinate transformation process (dq transformation process).

また、本実施形態では、電圧センサ４が相電圧を検出する場合について説明したが、これに限られない。例えば、電圧センサ４が線間電圧を検出する場合でも、本発明を適用することができる。この場合、三相二相変換部２１で行われる変換処理を、３個の線間電圧信号をα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換する処理にすればよい。または、三相二相変換部２１に、線間電圧信号を相電圧信号に変換する構成を追加して、線間電圧信号を相電圧信号Ｖｕ，Ｖｖ，Ｖｗに変換してから、α軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換してもよい。また、三相配線に、電圧センサ４の代わりに電流センサを配置し、電流センサから入力される３個の電流信号に基づいて逆相割合ｋを検出してもよい。 In addition, in this embodiment, the case where the voltage sensor 4 detects the phase voltage has been described, but this is not limited to this. For example, the present invention can be applied even when the voltage sensor 4 detects the line voltage. In this case, the conversion process performed by the three-phase to two-phase conversion unit 21 may be a process of converting three line voltage signals into an α-axis voltage signal Vα and a β-axis voltage signal Vβ. Alternatively, a configuration for converting line voltage signals into phase voltage signals may be added to the three-phase to two-phase conversion unit 21, and the line voltage signals may be converted into phase voltage signals Vu, Vv, and Vw, and then converted into the α-axis voltage signal Vα and the β-axis voltage signal Vβ. Alternatively, a current sensor may be arranged in the three-phase wiring instead of the voltage sensor 4, and the negative phase ratio k may be detected based on the three current signals input from the current sensor.

また、本実施形態では、演算部２による判定結果を表示部３に表示する場合について説明したが、これに限られない。例えば、判定結果が三相配線の接続異常を示す場合に、ブザーなどの音声で警告してもよい。この場合、異常検出装置Ａ１は、表示部３を備えなくてもよい。また、異常検出装置Ａ１は、表示部３を備えず、判定結果を異常検出装置Ａ１が配置された機器の表示部に表示してもよい。 In addition, in this embodiment, the case where the judgment result by the calculation unit 2 is displayed on the display unit 3 has been described, but this is not limited to this. For example, if the judgment result indicates a connection abnormality in the three-phase wiring, a warning may be issued by sound such as a buzzer. In this case, the abnormality detection device A1 does not need to have a display unit 3. Also, the abnormality detection device A1 may not have a display unit 3, and the judgment result may be displayed on the display unit of the equipment in which the abnormality detection device A1 is placed.

図４は、第２実施形態に係る異常検出装置Ａ２の全体構成を示すブロック図である。図４において、上記第１実施形態と同一または類似の要素には、上記第１実施形態と同一の符号を付している。本実施形態に係る異常検出装置Ａ２は、演算部２が不平衡率ｋ” に基づいて接続異常であるか否かを判定する点で、第１実施形態に係る異常検出装置Ａ１と異なる。 Figure 4 is a block diagram showing the overall configuration of an anomaly detection device A2 according to the second embodiment. In Figure 4, elements that are the same as or similar to those in the first embodiment are given the same reference numerals as those in the first embodiment. The anomaly detection device A2 according to this embodiment differs from the anomaly detection device A1 according to the first embodiment in that the calculation unit 2 determines whether or not there is a connection anomaly based on the unbalance rate k".

本実施形態に係る異常検出装置Ａ２は、実効値算出部２３および逆相割合算出部２５を備えておらず、逆相分抽出部２７、実効値算出部２８、および不平衡率算出部２９を備えている。異常検出装置Ａ２は、三相配線の不平衡率ｋ”を算出し、当該不平衡率ｋ” に基づいて接続異常であるか否かを判定する。 The abnormality detection device A2 according to this embodiment does not include an effective value calculation unit 23 and a negative-phase ratio calculation unit 25, but includes a negative-phase component extraction unit 27, an effective value calculation unit 28, and an unbalance ratio calculation unit 29. The abnormality detection device A2 calculates the unbalance ratio k" of the three-phase wiring and determines whether or not there is a connection abnormality based on the unbalance ratio k".

逆相分抽出部２７は、三相二相変換部２１より入力されるα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβから、基本波の逆相分信号Ｖα”，Ｖβ”を抽出する。逆相分抽出部２７は、抽出した逆相分信号Ｖα”，Ｖβ”を、実効値算出部２８に出力する。逆相分抽出部２７は、正相分抽出部２２と同様、複素係数フィルタを備えており、複数の複素係数バンドパスフィルタと、１個の複素係数ノッチフィルタと、を備えている。逆相分抽出部２７の複素係数バンドパスフィルタは、通過帯域を決定する正規化角周波数Ωdとして、系統電圧の基本波の逆相分の角周波数「－ω0」を正規化した「－ωd」があらかじめ設定されている。当該複素係数バンドパスフィルタは、その他の角周波数の信号（正相分および高調波成分）を好適に除去して、基本波の逆相分の信号を通過させる。逆相分抽出部２７の複素係数ノッチフィルタは、阻止帯域を決定する正規化角周波数Ωdとして、系統電圧の基本波の正相分の角周波数ω0を正規化したωdがあらかじめ設定されている。当該複素係数ノッチフィルタは、基本波の正相分の信号の通過を抑制することで、基本波の逆相分の信号を抽出する。なお、逆相分抽出部２７は、上記に限定されず、正相分抽出部２２と同様、様々な構成が考えられる。 The negative-phase-sequence component extraction unit 27 extracts the negative-phase-sequence components Vα”, Vβ” of the fundamental wave from the α-axis voltage signal Vα and the β-axis voltage signal Vβ input from the three-phase to two-phase conversion unit 21. The negative-phase-sequence component extraction unit 27 outputs the extracted negative-phase-sequence components Vα”, Vβ” to the effective value calculation unit 28. The negative-phase-sequence component extraction unit 27, like the positive-phase-sequence component extraction unit 22, is equipped with a complex coefficient filter, and is equipped with multiple complex coefficient band-pass filters and one complex coefficient notch filter. The complex coefficient band-pass filter of the negative-phase-sequence component extraction unit 27 is preset with “-ωd”, which is the normalized angular frequency “-ω0” of the negative-phase-sequence component of the fundamental wave of the system voltage, as the normalized angular frequency Ωd that determines the passband. The complex coefficient band-pass filter preferably removes signals of other angular frequencies (positive-sequence components and harmonic components) and passes the negative-phase-sequence component of the fundamental wave. The complex coefficient notch filter of the negative-phase-sequence component extraction unit 27 is preset with a normalized angular frequency Ωd that determines the stopband, which is ωd obtained by normalizing the angular frequency ω0 of the positive-phase-sequence component of the fundamental wave of the system voltage. The complex coefficient notch filter extracts the negative-phase-sequence component of the fundamental wave by suppressing the passage of the positive-phase-sequence component of the fundamental wave. Note that the negative-phase-sequence component extraction unit 27 is not limited to the above, and various configurations are possible, similar to the positive-phase-sequence component extraction unit 22.

実効値算出部２８は、逆相分抽出部２７から入力される逆相分信号Ｖα”および逆相分信号Ｖβ”に基づいて、三相配線の電圧から逆相分を抽出した電圧の実効値Ｖ”を算出する。具体的には、実効値算出部２８は、逆相分信号Ｖα”を２乗した値と逆相分信号Ｖβ”を２乗した値との加算値の平方根を、実効値Ｖ”（＝√（Ｖα”2＋Ｖβ”2））として算出する。実効値算出部２８は、算出した実効値Ｖ”を不平衡率算出部２９に出力する。 Based on the negative-phase-sequence component signal Vα″ and negative-phase-sequence component signal Vβ″ input from the negative-phase-sequence component extraction unit 27, the effective value calculation unit 28 calculates the effective value V″ of the voltage obtained by extracting the negative-phase-sequence component from the voltage of the three-phase wiring. Specifically, the effective value calculation unit 28 calculates the square root of the sum of the value obtained by squaring the negative-phase-sequence component signal Vα″ and the value obtained by squaring the negative-phase-sequence component signal Vβ″, as the effective value V″ (=√(Vα″ 2 + Vβ″ 2 )). The effective value calculation unit 28 outputs the calculated effective value V″ to the unbalance rate calculation unit 29.

本実施形態に係る実効値算出部２４は、第１実施形態とは異なり、（５／３）を乗算する前の値を、実効値Ｖ’（＝√（Ｖα’2＋Ｖβ’2））として算出する。逆相分抽出部２７から出力される逆相分信号Ｖα”，Ｖβ”も、逆相分抽出部２７のフィルタの特性により、正相分抽出部２２から出力される正相分信号Ｖα’，Ｖβ’と同様、（３／５）に減衰している。したがって、減衰した信号同士で、不平衡率ｋ”を算出するためである。実効値算出部２４は、算出した実効値Ｖ’を不平衡率算出部２９に出力する。 Unlike the first embodiment, the effective value calculation unit 24 in this embodiment calculates the value before multiplication by (5/3) as the effective value V' (=√( Vα'2 + Vβ'2 )). The negative sequence component signals Vα", Vβ" output from the negative sequence component extraction unit 27 are also attenuated to (3/5) due to the filter characteristics of the negative sequence component extraction unit 27, similar to the positive sequence component signals Vα', Vβ' output from the positive sequence component extraction unit 22. This is because the unbalance ratio k" is calculated using the attenuated signals. The effective value calculation unit 24 outputs the calculated effective value V' to the unbalance ratio calculation unit 29.

不平衡率算出部２９は、実効値算出部２４より入力される実効値Ｖ’と、実効値算出部２８より入力される実効値Ｖ”とから、不平衡率ｋ”を算出する。具体的には、不平衡率算出部２９は、実効値Ｖ”を実効値Ｖ’で除算し、１００を乗算した値を、不平衡率ｋ”（＝Ｖ”・１００／Ｖ’）として算出する。不平衡率算出部２９は、算出した不平衡率ｋ”を判定部２６に出力する。 The unbalance rate calculation unit 29 calculates the unbalance rate k" from the effective value V' input from the effective value calculation unit 24 and the effective value V" input from the effective value calculation unit 28. Specifically, the unbalance rate calculation unit 29 divides the effective value V" by the effective value V' and multiplies the result by 100 to calculate the unbalance rate k" (= V" · 100/V'). The unbalance rate calculation unit 29 outputs the calculated unbalance rate k" to the determination unit 26.

三相配線が正しい相順で接続され、三相配線の電圧が正相分だけで構成された理想的な状態であった場合、逆相分抽出部２７から出力された信号の実効値Ｖ”が０になる。この場合、不平衡率ｋ”は０％になる。しかし、実際には、三相配線が正しい相順で接続されている場合でも、三相配線の電圧には逆相分の電圧も含まれているので、実効値Ｖ”は「０」に近い値になる。よって、不平衡率ｋ”は０％より大きい値になる。一方、三相配線が逆相の相順で接続されていると、三相配線の電圧には正相分の電圧がほとんど含まれないので、正相分抽出部２２から出力された信号の実効値Ｖ’は「０」に近い値になる。この場合、不平衡率ｋ”は１００％より大きい値になる。 In an ideal state where the three-phase wiring is connected in the correct phase sequence and the voltage of the three-phase wiring is composed only of positive-phase components, the effective value V" of the signal output from the negative-phase component extraction unit 27 is 0. In this case, the unbalance rate k" is 0%. However, in reality, even when the three-phase wiring is connected in the correct phase sequence, the voltage of the three-phase wiring also contains the negative-phase component voltage, so the effective value V" is close to "0". Therefore, the unbalance rate k" is a value greater than 0%. On the other hand, if the three-phase wiring is connected in the reverse phase sequence, the voltage of the three-phase wiring contains almost no positive-phase component voltage, so the effective value V' of the signal output from the positive-phase component extraction unit 22 is close to "0". In this case, the unbalance rate k" is a value greater than 100%.

判定部２６は、不平衡率算出部２９が算出した不平衡率ｋ”を入力され、不平衡率ｋ”とあらかじめ設定されている所定の閾値ｋ”0とを比較することで、三相配線の接続異常であるか否かを判定する。閾値ｋ”0は、三相配線の接続異常を判定できる値が、シミュレーションなどに基づいて適宜設定される。閾値ｋ”0は、例えば８０％が設定されるが、これに限定されない。判定部２６は、不平衡率ｋ”が閾値ｋ”0以上の状態が所定時間Ｔ0以上経過した場合に接続異常であると判定し、それ以外の場合には正常であると判定する。 The determination unit 26 receives the unbalance rate k" calculated by the unbalance rate calculation unit 29, and compares the unbalance rate k" with a predetermined threshold value k" 0 that is set in advance to determine whether or not there is a connection abnormality in the three-phase wiring. The threshold value k" 0 is set as appropriate based on simulations or the like to determine whether or not there is a connection abnormality in the three-phase wiring. The threshold value k" 0 is set to, for example, 80%, but is not limited to this. The determination unit 26 determines that there is a connection abnormality when the state in which the unbalance rate k" is equal to or greater than the threshold value k" 0 has continued for a predetermined time T0 or more, and determines that the connection is normal in other cases.

本実施形態によると、不平衡率算出部２９が実効値Ｖ’と実効値Ｖ”とから不平衡率ｋ”を算出し、判定部２６が不平衡率ｋ”と所定の閾値ｋ”0とを比較することで、三相配線の接続異常を判定する。これにより、異常検出装置Ａ２は、三相配線の接続異常を検出できる。また、異常検出装置Ａ２は、接続異常の検出においてゼロクロスタイミングを利用しないので、いずれのタイミングにおいても、実施される処理は共通している。したがって、異常検出装置Ａ２は、処理時間の変動を抑制できる。 According to this embodiment, the unbalance ratio calculation unit 29 calculates the unbalance ratio k" from the effective value V' and the effective value V", and the determination unit 26 compares the unbalance ratio k" with a predetermined threshold value k" 0 to determine a connection abnormality in the three-phase wiring. In this way, the abnormality detection device A2 can detect a connection abnormality in the three-phase wiring. Furthermore, because the abnormality detection device A2 does not use zero-crossing timing to detect a connection abnormality, the processing performed is the same regardless of the timing. Therefore, the abnormality detection device A2 can suppress fluctuations in processing time.

また、本実施形態においても、三相二相変換部２１が３個の相電圧信号Ｖｕ，Ｖｖ，Ｖｗをα軸電圧信号Ｖαおよびβ軸電圧信号Ｖβに変換し、正相分抽出部２２が基本波の正相分信号Ｖα’，Ｖβ’を抽出し、実効値算出部２４が実効値Ｖ’を算出する。また、本実施形態によると、逆相分抽出部２７が基本波の逆相分信号Ｖα”，Ｖβ”を抽出し、実効値算出部２８が三相配線の電圧から逆相分を抽出した電圧の実効値Ｖ”を算出する。不平衡率算出部２９は、実効値Ｖ’と実効値Ｖ”とから不平衡率ｋ”を算出する。このように、異常検出装置Ａ２は、簡単な演算処理で不平衡率ｋ”を検出できる。 また、本実施形態によると、逆相分抽出部２７は、複数の複素係数バンドパスフィルタ（帯域通過型の複素係数フィルタ）と、１個の複素係数ノッチフィルタ（帯域阻止型の複素係数フィルタ）とを備えている。したがって、逆相分抽出部２７は、精度よく、基本波の逆相分の信号を抽出できる。 Also in this embodiment, the three-phase to two-phase conversion unit 21 converts the three phase voltage signals Vu, Vv, and Vw into an α-axis voltage signal Vα and a β-axis voltage signal Vβ, the positive-phase component extraction unit 22 extracts the positive-phase component signals Vα' and Vβ' of the fundamental wave, and the effective value calculation unit 24 calculates the effective value V'. Also, according to this embodiment, the negative-phase component extraction unit 27 extracts the negative-phase component signals Vα", Vβ" of the fundamental wave, and the effective value calculation unit 28 calculates the effective value V" of the voltage obtained by extracting the negative-phase component from the voltage of the three-phase wiring. The unbalance rate calculation unit 29 calculates the unbalance rate k" from the effective value V' and the effective value V". In this way, the abnormality detection device A2 can detect the unbalance rate k" by simple calculation processing. Also, according to this embodiment, the negative-phase component extraction unit 27 has a plurality of complex coefficient bandpass filters (complex coefficient filters of band pass type) and one complex coefficient notch filter (complex coefficient filter of band rejection type). Therefore, the negative-phase-sequence extraction unit 27 can accurately extract the signal that is the negative-phase-sequence of the fundamental wave.

本発明に係る異常検出装置は、上述した実施形態に限定されるものではない。本発明に係る異常検出装置の各部の具体的な構成は、種々に設計変更自在である。 The anomaly detection device according to the present invention is not limited to the above-described embodiment. The specific configuration of each part of the anomaly detection device according to the present invention can be freely designed in various ways.

Ａ１～Ａ２：異常検出装置、２１：三相二相変換部、２２：正相分抽出部、２２１：複素係数バンドパスフィルタ、２２２：複素係数ノッチフィルタ、２３，２４，２８：実効値算出部、２５：逆相割合算出部、２６：判定部、２７：逆相分抽出部、２９：不平衡率算出部 A1-A2: Anomaly detection device, 21: Three-phase to two-phase conversion section, 22: Positive-phase component extraction section, 221: Complex coefficient band-pass filter, 222: Complex coefficient notch filter, 23, 24, 28: Effective value calculation section, 25: Negative-phase ratio calculation section, 26: Judgment section, 27: Negative-phase component extraction section, 29: Unbalance ratio calculation section

Claims (5)

三相配線の三相交流に基づく３個の信号を第１の信号および第２の信号に変換する三相二相変換部と、
前記第１の信号に含まれる正相分の信号である第１の正相分信号と、前記第２の信号に含まれる正相分の信号である第２の正相分信号とを、それぞれ抽出する正相分抽出部と、
前記第１の信号および前記第２の信号に基づいて、第１実効値を算出する第１実効値算出部と、
前記第１の正相分信号および前記第２の正相分信号に基づいて、第２実効値を算出する第２実効値算出部と、
前記第１実効値および前記第２実効値に基づく割合を算出する割合算出部と、
前記割合と所定の閾値とを比較することで、前記三相配線の接続異常を判定する判定部と、
を備えている異常検出装置。 a three-phase to two-phase conversion unit that converts three signals based on three-phase AC of a three-phase wiring into a first signal and a second signal;
a positive-phase-sequence component extracting unit that extracts a first positive-phase-sequence signal that is a positive-phase-sequence signal included in the first signal and a second positive-phase-sequence signal that is a positive-phase-sequence signal included in the second signal;
a first effective value calculation unit that calculates a first effective value based on the first signal and the second signal;
a second effective value calculation unit that calculates a second effective value based on the first positive sequence signal and the second positive sequence signal;
a ratio calculation unit that calculates a ratio based on the first effective value and the second effective value;
a determination unit that determines a connection anomaly of the three-phase wiring by comparing the ratio with a predetermined threshold value;
An abnormality detection device comprising: 前記割合算出部は、前記第１実効値に対する、前記第１実効値から前記第２実効値を減じた差の割合を算出する、
請求項１に記載の異常検出装置。 the ratio calculation unit calculates a ratio of a difference obtained by subtracting the second effective value from the first effective value to the first effective value.
The abnormality detection device according to claim 1 . 前記閾値は、６０％より大きく、１００％より小さい、
請求項２に記載の異常検出装置。 The threshold is greater than 60% and less than 100%.
The abnormality detection device according to claim 2 . 前記正相分抽出部は、複数の帯域通過型の複素係数フィルタと、帯域阻止型の複素係数フィルタとを用いて、前記第１の正相分信号および前記第２の正相分信号を抽出する、
請求項１ないし３のいずれかに記載の異常検出装置。 the positive-phase-sequence component extracting unit extracts the first positive-phase-sequence signal and the second positive-phase-sequence signal using a plurality of band-pass complex-coefficient filters and a band-rejection complex-coefficient filter;
4. The abnormality detection device according to claim 1. 三相配線の三相交流に基づく３個の信号を第１の信号および第２の信号に変換する三相二相変換部と、
前記第１の信号に含まれる正相分の信号である第１の正相分信号と、前記第２の信号に含まれる正相分の信号である第２の正相分信号とを、それぞれ抽出する正相分抽出部と、
前記第１の正相分信号および前記第２の正相分信号に基づいて、正相分実効値を算出する正相分実効値算出部と、
前記第１の信号に含まれる逆相分の信号である第１の逆相分信号と、前記第２の信号に含まれる逆相分の信号である第２の逆相分信号とを、それぞれ抽出する逆相分抽出部と、
前記第１の逆相分信号および前記第２の逆相分信号に基づいて、逆相分実効値を算出する逆相分実効値算出部と、
前記正相分実効値と前記逆相分実効値とから不平衡率を算出する不平衡率算出部と、
前記不平衡率と所定の閾値とを比較することで、前記三相配線の接続異常を判定する判定部と、
を備えている異常検出装置。 a three-phase to two-phase conversion unit that converts three signals based on three-phase AC of a three-phase wiring into a first signal and a second signal;
a positive-phase-sequence component extracting unit that extracts a first positive-phase-sequence signal that is a positive-phase-sequence signal included in the first signal and a second positive-phase-sequence signal that is a positive-phase-sequence signal included in the second signal;
a positive sequence component effective value calculation unit that calculates a positive sequence component effective value based on the first positive sequence component signal and the second positive sequence component signal;
a negative-phase-sequence component extracting unit for extracting a first negative-phase-sequence component signal that is a negative-phase-sequence component signal included in the first signal and a second negative-phase-sequence component signal that is a negative-phase-sequence component signal included in the second signal;
a negative-phase-sequence effective value calculation unit that calculates a negative-phase-sequence effective value based on the first negative-phase-sequence signal and the second negative-phase-sequence signal;
an unbalance factor calculation unit that calculates an unbalance factor from the positive phase effective value and the negative phase effective value;
a determination unit that determines a connection abnormality of the three-phase wiring by comparing the unbalance rate with a predetermined threshold value;
An abnormality detection device comprising:
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