JP4579591B2

JP4579591B2 - Power converter

Info

Publication number: JP4579591B2
Application number: JP2004187932A
Authority: JP
Inventors: 禎宏吉田
Original assignee: Toshiba Mitsubishi Electric Industrial Systems Corp
Current assignee: Toshiba Mitsubishi Electric Industrial Systems Corp
Priority date: 2004-06-25
Filing date: 2004-06-25
Publication date: 2010-11-10
Anticipated expiration: 2024-06-25
Also published as: JP2006014483A

Description

この発明は、電力変換装置に関するものであり、特に複数の電力変換モジュールで構成された電力変換装置において、伝送路ケーブルのインピーダンス等による歪みのない同期したキャリア信号を有するものに係る。 The present invention relates to a power conversion device, and particularly relates to a power conversion device including a plurality of power conversion modules having a synchronized carrier signal without distortion due to impedance of a transmission line cable or the like.

従来、複数台設置された電力変換装置の制御方法として、前記各電力変換装置を制御するための信号をシリアル信号に変換して出力するシリアル送信回路を有する上位コントローラと、前記各電力変換装置にそれぞれ配置されたシリアル受信回路において、シリアル伝送される信号に電圧指令やＰＷＭパターン指令、ＰＷＭ同期信号を含めて伝送し、この同期信号の出力毎にＰＷＭ生成部をリセットすることが示されている（例えば特許文献１参照）。 Conventionally, as a method of controlling a plurality of power converters installed, a host controller having a serial transmission circuit that converts a signal for controlling each power converter into a serial signal and outputs the serial signal, and each power converter In each serial receiving circuit arranged, it is shown that a serially transmitted signal is transmitted including a voltage command, a PWM pattern command, and a PWM synchronization signal, and the PWM generator is reset every time this synchronization signal is output. (For example, refer to Patent Document 1).

特開２００２−３４５２５２号公報（図１）JP 2002-345252 A (FIG. 1)

しかしながら前記特許文献１に開示されたものは、シリアル伝送される信号内の同期信号をキャリア同期に用いているため、キャリアを同期化する同期はシリアル伝送信号の状態に左右されるので、キャリア１周期毎に同期できなく、キャリア間の誤差が大きくなる場合があるという問題点を有している。 However, since the one disclosed in Patent Document 1 uses the synchronization signal in the serially transmitted signal for carrier synchronization, the synchronization for synchronizing the carrier depends on the state of the serial transmission signal. There is a problem that synchronization cannot be performed every period, and an error between carriers may increase.

この発明は、前記のような課題を解決するためになされたものであって、キャリア同期専用の信号を用いることによって、キャリアを１周期毎に同期可能とし、キャリア間の誤差を小さくすることを目的としている。 The present invention has been made to solve the above-described problems, and by using a signal dedicated to carrier synchronization, it is possible to synchronize carriers for each period and reduce errors between carriers. It is aimed.

第１の発明に係る電力変換装置には制御モジュールと、制御モジュールに伝送路を介して接続された複数の電力変換モジュールが備えられており、
電力変換モジュールにはキャリア信号発生回路と、電圧指令発生回路と、比較器と、スイッチング回路と、さらに加えて基準電圧発生回路と、検出幅付き比較器と、ラッチ付バッファとで構成される前記キャリア信号発生回路の異常停止回路とが設けられており、キャリア信号発生回路は、制御モジュールに設けられた同期信号出力回路から出力されて、伝送路の影響を受けた同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるとともに、キャリア信号発生回路の出力するキャリア信号と基準電圧発生回路の出力とを、検出幅付き比較器が比較し、その差が許容値以上の場合に異常信号をラッチ付バッファに出力し、ラッチ付バッファは同期信号Ｆ’の変化するタイミングで検出幅付き比較器が出力する異常信号を入力すると、キャリア信号発生回路異常検出信号をスイッチング回路に出力し、スイッチング回路はスイッチング動作を停止するものである。 The power conversion device according to the first invention includes a control module, and a plurality of power conversion modules connected to the control module via a transmission line,
The power conversion module includes a carrier signal generation circuit, a voltage command generation circuit, a comparator, a switching circuit , a reference voltage generation circuit, a comparator with a detection width, and a buffer with a latch. and abnormal stoppage circuit of the carrier signal generating circuit is provided with a carrier signal generating circuit is output from the synchronizing signal output circuit provided in the control module, the change in the affected transmission line synchronization signal F ' The carrier signal detected and synchronized to an arbitrary phase is output, and the comparator compares the carrier signal with the output signal of the voltage command generation circuit, and outputs the result to the switching circuit. A comparator with detection width compares the carrier signal to be output with the output of the reference voltage generation circuit, and if the difference exceeds the allowable value, an abnormal signal is latched. When the abnormal signal output from the comparator with detection width is input to the buffer with latch and the timing at which the synchronization signal F ′ changes, the latched buffer outputs the carrier signal generation circuit abnormality detection signal to the switching circuit, and the switching circuit switches The operation is stopped.

第２の発明に係る電力変換装置は、伝送路を介して接続された複数の電力変換モジュールを備え、
電力変換モジュールには同期信号出力回路と、キャリア信号発生回路と、電圧指令発生回路と、比較器と、スイッチング回路と、第１の同期異常検出回路と、第２の同期異常検出回路および接続回路とが設けられており、
第１の同期異常検出回路は、同期信号出力回路から出力されて伝送路の影響を受けた同期信号Ｆ’が異常検出期間内に変化しない場合に、同期異常を出力するものであり、異常検出期間は複数の電力変換モジュール毎にそれぞれ異なるように設定されており、第２回の同期異常検出回路は、同期信号出力回路の出力が所定の検出期間を越えても変化しない場合に、同期信号出力回路が異常と出力するものであり、接続回路は、第１の同期異常検出回路の出力により、同期信号出力回路を伝送路に接続するとともに、第２の同期異常検出回路の出力により、同期信号出力回路を伝送路から切り離すものであり、同期信号出力回路が正常な場合、異常検出期間が最も短い検出期間に設定されている第１の同期異常検出回路が設けられている電力変換モジュール内の同期信号出力回路のみが接続回路を介して伝送路に接続され、その出力が各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるとともに、第２の同期異常検出回路が同期信号出力回路の異常を検出すると、接続回路は同期信号出力回路を伝送路から切り離し、この状態が異常検出期間が最も短い期間の次の２番目に短い検出期間を越えて継続すると、この検出期間が設定されている第２の同期異常検出回路が設けられている電力変換モジュール内の同期信号出力回路が、接続回路を介して伝送回路に接続され、その出力が各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるものであり、以下同様に同期信号出力回路に異常が発生すると、設定された異常検出期間の長さに基づき順次概当する電力変換モジュールの同期信号出力回路に切り替わりその出力が、各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるものである。 Power converter according to the second invention, e Bei a plurality of power conversion modules connected via a transmission path,
The power conversion module includes a synchronization signal output circuit, a carrier signal generation circuit, a voltage command generation circuit, a comparator, a switching circuit , a first synchronization abnormality detection circuit, a second synchronization abnormality detection circuit, and a connection circuit. And is provided,
The first synchronization abnormality detection circuit outputs a synchronization abnormality when the synchronization signal F ′ output from the synchronization signal output circuit and affected by the transmission path does not change within the abnormality detection period. The period is set to be different for each of the plurality of power conversion modules, and the second synchronization abnormality detection circuit does not change even if the output of the synchronization signal output circuit exceeds the predetermined detection period. The output circuit outputs an abnormality, and the connection circuit connects the synchronization signal output circuit to the transmission line by the output of the first synchronization abnormality detection circuit, and synchronizes by the output of the second synchronization abnormality detection circuit. Power conversion in which the signal output circuit is separated from the transmission line, and when the synchronization signal output circuit is normal, the first synchronization abnormality detection circuit having the shortest abnormality detection period is set. Only the synchronization signal output circuit in the module is connected to the transmission line via the connection circuit, and the output is output to each power conversion module, and each carrier signal generation circuit detects the change of the synchronization signal F ′ and sets it to an arbitrary phase. The synchronized carrier signal is output, the comparator compares the carrier signal with the output signal of the voltage command generation circuit, the result is output to the switching circuit, and the second synchronization abnormality detection circuit outputs the synchronization signal. When a circuit abnormality is detected, the connection circuit disconnects the synchronization signal output circuit from the transmission line, and when this state continues beyond the second shortest detection period after the shortest abnormality detection period, this detection period is set. The synchronization signal output circuit in the power conversion module in which the second synchronization abnormality detection circuit is provided is connected to the transmission circuit via the connection circuit, and the output is Output to each power conversion module, each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized with an arbitrary phase, and outputs a carrier signal and an output signal of the voltage command generation circuit by a comparator And the result is output to the switching circuit. Similarly, when an abnormality occurs in the synchronous signal output circuit, the power conversion module that sequentially approximates based on the length of the set abnormality detection period. Switching to the synchronization signal output circuit, the output is output to each power conversion module, each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized to an arbitrary phase, by the comparator The carrier signal is compared with the output signal of the voltage command generation circuit, and the result is output to the switching circuit.

第１の発明の電力変換装置は、各電力変換モジュールに設けられたキャリア信号発生回路が、制御モジュールに設けられた同期信号出力回路から出力されて、伝送路の影響を受けた同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力するので、伝送路のインピーダンス等による歪みのない同期したキャリア信号を得ることができるとともに、キャリア信号発生回路の出力するキャリア信号と基準電圧発生回路の出力とを、検出幅付き比較器が比較し、その差が許容値以上の場合に異常信号をラッチ付バッファに出力し、ラッチ付バッファは同期信号Ｆ’の変化するタイミングで検出幅付き比較器が出力する異常信号を入力すると、キャリア信号発生回路異常検出信号をスイッチング回路に出力し、スイッチング回路はスイッチング動作を停止するので、容易にキャリア異常を検出できる。 In the power conversion device of the first invention, the carrier signal generation circuit provided in each power conversion module is output from the synchronization signal output circuit provided in the control module, and the synchronization signal F ′ influenced by the transmission path is received. The carrier signal synchronized with an arbitrary phase is output, the carrier signal is compared with the output signal of the voltage command generation circuit, and the result is output to the switching circuit. A synchronous carrier signal without distortion due to impedance, etc. can be obtained , and a comparator with a detection width compares the carrier signal output from the carrier signal generation circuit with the output of the reference voltage generation circuit, and the difference is an allowable value. In the above case, an abnormal signal is output to the buffer with latch, and the comparator with detection width outputs the buffer with latch at the timing when the synchronization signal F ′ changes. If you enter an abnormal signal, and outputs a carrier signal generating circuit abnormality detection signal to a switching circuit, the switching circuit will stop the switching operation, can easily detect the carrier abnormality.

第２の発明の電力変換装置は、伝送路を介して接続された複数の電力変換モジュールを備え、電力変換モジュールには同期信号出力回路と、キャリア信号発生回路と、電圧指令発生回路と、比較器と、スイッチング回路と、第１の同期異常検出回路と、第２の同期異常検出回路および接続回路とが設けられており、第１の同期異常検出回路は、同期信号出力回路から出力されて伝送路の影響を受けた同期信号Ｆ’が異常検出期間内に変化しない場合に、同期異常を出力するものであり、異常検出期間は複数の電力変換モジュール毎にそれぞれ異なるように設定されており、第２回の同期異常検出回路は、同期信号出力回路の出力が所定の検出期間を越えても変化しない場合に、同期信号出力回路が異常と出力するものであり、接続回路は第１の同期異常検出回路の出力により、同期信号出力回路を伝送路に接続するとともに、第２の同期異常検出回路の出力により、同期信号出力回路を伝送路から切り離すものであり、同期信号出力回路が正常な場合、異常検出期間が最も短い検出期間に設定されている第１の同期異常検出回路が設けられている電力変換モジュール内の同期信号出力回路のみが接続回路を介して伝送路に接続され、その出力が各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるとともに、第２の同期異常検出回路が同期信号出力回路の異常を検出すると、接続回路は同期信号出力回路を伝送路から切り離し、この状態が異常検出期間が最も短い期間の次の２番目に短い検出期間を越えて継続すると、この検出期間が設定されている第２の同期異常検出回路が設けられている電力変換モジュール内の同期信号出力回路が、接続回路を介して伝送回路に接続され、その出力が各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるものであり、以下同様に同期信号出力回路に異常が発生すると、設定された異常検出期間の長さに基づき順次概当する電力変換モジュールの同期信号出力回路に切り替わりその出力が、各電力変換モジュールに出力され、各キャリア信号発生回路は同期信号Ｆ’の変化を検出、任意の位相に同期化させたキャリア信号を出力し、比較器によってキャリア信号と電圧指令発生回路の出力信号とが比較され、その結果がスイッチング回路に出力されるので、使用中の同期信号出力回路に異常が発生しても、異常な同期信号出力回路の切り離し及び健全な同期信号出力回路の接続を行うことができるため、装置全体の信頼性を向上させることができる。 Power converter of the second invention comprises a plurality of power conversion modules connected via a transmission path, and the synchronization signal output circuit in the power conversion module, a carrier signal generating circuit, and a voltage command generating circuit, A comparator, a switching circuit , a first synchronization abnormality detection circuit, a second synchronization abnormality detection circuit, and a connection circuit are provided, and the first synchronization abnormality detection circuit is output from the synchronization signal output circuit. When the synchronization signal F ′ affected by the transmission line does not change within the abnormality detection period, a synchronization abnormality is output. The abnormality detection period is set to be different for each of the plurality of power conversion modules. In the second synchronization abnormality detection circuit, when the output of the synchronization signal output circuit does not change even after a predetermined detection period, the synchronization signal output circuit outputs an abnormality, and the connection circuit is the first circuit. of The synchronization signal output circuit is connected to the transmission line by the output of the synchronization abnormality detection circuit, and the synchronization signal output circuit is disconnected from the transmission line by the output of the second synchronization abnormality detection circuit. In this case, only the synchronization signal output circuit in the power conversion module provided with the first synchronization abnormality detection circuit that is set to the detection period with the shortest abnormality detection period is connected to the transmission line via the connection circuit, The output is output to each power conversion module, each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized with an arbitrary phase, and a carrier signal and voltage command generation circuit by a comparator And the result is output to the switching circuit, and when the second synchronization abnormality detection circuit detects an abnormality in the synchronization signal output circuit, The circuit disconnects the synchronization signal output circuit from the transmission line, and when this state continues beyond the second shortest detection period next to the shortest abnormality detection period, the second synchronization abnormality in which this detection period is set The synchronization signal output circuit in the power conversion module provided with the detection circuit is connected to the transmission circuit via the connection circuit, and the output is output to each power conversion module. Each carrier signal generation circuit is synchronized with the synchronization signal F ′. Is detected, the carrier signal synchronized with an arbitrary phase is output, the carrier signal is compared with the output signal of the voltage command generation circuit by the comparator, and the result is output to the switching circuit, Similarly, when an abnormality occurs in the synchronization signal output circuit, the system switches to the synchronization signal output circuit of the power conversion module, which is sequentially approximated based on the set length of the abnormality detection period. The output is output to each power conversion module, and each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized with an arbitrary phase, and generates a carrier signal and a voltage command by a comparator. Since the output signal of the circuit is compared and the result is output to the switching circuit, even if an abnormality occurs in the synchronizing signal output circuit in use, the abnormal synchronizing signal output circuit is disconnected and the healthy synchronizing signal output circuit Therefore, the reliability of the entire apparatus can be improved.

実施の形態１．
以下、この発明の実施の形態１を図に基づいて説明する。
図１（ａ）は、実施の形態１に係る電力変換装置５００の構成を示すブロック図である。同図において、制御モジュール１には同期信号出力回路１０１を、複数の、この場合２台の電力変換モジュール２ａ、２ｂにはキャリア信号発生回路１０２ａ、１０２ｂをそれぞれ設けており、伝送路３のケーブルで前記電力変換モジュール２ａ、２ｂ間を接続している。同時に、電力変換モジュール２ａ、２ｂ内には電圧指令発生回路１０３ａ、１０３ｂと比較器１０４ａ、１０４ｂと、スイッチング回路１０５ａ、１０５ｂをそれぞれ設けている。
このような構成において前記制御モジュール１に設けられた同期信号出力回路１０１から出力される同期信号のＨｉｇｈ→Ｌｏｗの変化により、キャリア信号発生回路１０２ａ、１０２ｂから出力されるキャリア信号Ｃａ、Ｃｂをキャリア下限に同期させる。そして、キャリア信号Ｃａ、Ｃｂと電圧指令発生回路１０３ａ、１０３ｂの出力信号を比較器１０４ａ、１０４ｂで比較し、その結果によりスイッチング回路１０５ａ、１０５ｂを動作させる。 Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1A is a block diagram showing a configuration of power conversion apparatus 500 according to Embodiment 1. In the figure, the control module 1 is provided with a synchronization signal output circuit 101, and the plurality of power conversion modules 2a and 2b in this case are provided with carrier signal generation circuits 102a and 102b, respectively. The power conversion modules 2a and 2b are connected. At the same time, voltage command generation circuits 103a and 103b, comparators 104a and 104b, and switching circuits 105a and 105b are provided in the power conversion modules 2a and 2b, respectively.
In such a configuration, the carrier signals Ca and Cb output from the carrier signal generation circuits 102a and 102b are changed from the carrier signal Ca and Cb to the carrier by the change of the synchronization signal High → Low output from the synchronization signal output circuit 101 provided in the control module 1. Synchronize with the lower limit. Then, the carrier signals Ca and Cb and the output signals of the voltage command generation circuits 103a and 103b are compared by the comparators 104a and 104b, and the switching circuits 105a and 105b are operated according to the result.

図１（ｂ）は、前記実施の形態１でのキャリア波形を示す。同図において、制御モジュール１内の同期信号出力回路１０１より出力された同期信号Ｆは、各電力変換モジュール２ａ、２ｂでは伝送路３のインピーダンス等により波形に歪みが生じ同期信号Ｆ’となるが、キャリア信号発生回路１０２ａ、１０２ｂでは前記同期信号Ｆ’のＨｉｇｈ→Ｌｏｗの変化のみを検出しているため、インピーダンス等の影響による波形の形状をほぼ無視することができる。
このため、図１（ｂ）に示すようにキャリア信号発生回路１０２ａから出力されたキャリア信号Ｃａと、キャリア信号発生回路１０２ｂから出力されたキャリア信号Ｃｂとを同期信号Ｆ’のＨｉｇｈ→Ｌｏｗの変化により、それぞれキャリア下限に同期させることができる。
そして、キャリア信号発生回路１０２ａと比較器１０４ａ、及びキャリア信号発生回路１０２ｂと比較器１０４ｂはそれぞれが同じ電力変換モジュール２ａと２ｂ内にあるため、キャリア信号Ｃａ、Ｃｂは伝送路３のインピーダンスの影響を受けず、歪みのないキャリア信号を得ることができる。 FIG. 1B shows the carrier waveform in the first embodiment. In the figure, the synchronization signal F output from the synchronization signal output circuit 101 in the control module 1 is distorted in the waveform due to the impedance of the transmission line 3 in each power conversion module 2a, 2b, and becomes the synchronization signal F ′. Since the carrier signal generation circuits 102a and 102b detect only the change of the synchronization signal F ′ from High to Low, the waveform shape due to the influence of impedance or the like can be almost ignored.
Therefore, as shown in FIG. 1B, the carrier signal Ca output from the carrier signal generation circuit 102a and the carrier signal Cb output from the carrier signal generation circuit 102b are changed from High to Low of the synchronization signal F ′. Thus, each can be synchronized with the lower limit of the carrier.
The comparators 104a and the carrier signal generating circuit 102a, and since the comparator 104b and the carrier signal generating circuit 102b, each in the same power conversion module 2a and the 2b, the carrier signal Ca, Cb is the influence of the impedance of the transmission line 3 Thus, a carrier signal without distortion can be obtained.

図１では電力変換モジュールが２台の例を示しているが、必ずしもこれに限らず電力変換モジュールが３台以上の電力変換装置にも適用できる。なお、ここでは同期信号のＨｉｇｈ→Ｌｏｗの変化によりキャリア信号をキャリア下限に同期させる例を示したが、同期信号のＬｏｗ→Ｈｉｇｈ変化や任意のキャリア位相に同期させても同様の効果が得られることは言うまでもない。 Although FIG. 1 shows an example in which there are two power conversion modules, the present invention is not necessarily limited to this, and the present invention can also be applied to a power conversion device having three or more power conversion modules. In this example, the carrier signal is synchronized with the carrier lower limit by the change of the synchronization signal from High to Low, but the same effect can be obtained by synchronizing with the Low to High change of the synchronization signal or an arbitrary carrier phase. Needless to say.

以上のように、各電力変換モジュールそれぞれにキャリア信号発生回路を設け、制御モジュールから各電力変換モジュールヘ同期信号を出力して各電力変換モジュールのキャリア信号を同期させることにより、ケープルのインピーダンス等による歪みのない同期したキャリア信号を得ることができる。 As described above, each power conversion module is provided with a carrier signal generation circuit, and a synchronization signal is output from the control module to each power conversion module to synchronize the carrier signal of each power conversion module. A synchronized carrier signal without distortion can be obtained.

実施の形態２．
次に実施の形態２に係る電力変換装置５００ａの構成のブロック図を図２（ａ）に示す。同図において、制御モジュール１に同期信号出力回路１０１を、複数の、この場合２台の電力変換モジュール２ａ、２ｂにはキャリア信号発生回路１０２ａ、１０２ｂをそれぞれ設けており、伝送路３のケーブルで前記電力変換モジュール２ａ、２ｂ間を接続している。同時に、電力変換モジュール２ａ、２ｂ内には電圧指令発生回路１０３ａ、１０３ｂと比較器１０４ａ、１０４ｂと、スイッチング回路１０５ａ、１０５ｂをそれぞれ設け、さらにそれぞれに基準電圧発生回路１０６ａ、１０６ｂと、検出幅付き比較器１０７ａ、１０７ｂと、ラッチ付バッファ１０８ａ、１０８ｂとで構成される異常停止回路が設けられている。
前記基準電圧発生回路１０６ａ、１０６ｂは前記電力変換モジュール２ａ、２ｂ内にキャリア下限時に相当する電圧を発生する。 Embodiment 2. FIG.
Next, FIG. 2A shows a block diagram of a configuration of the power conversion device 500a according to the second embodiment. In the figure, a synchronization signal output circuit 101 is provided in the control module 1, and carrier signal generation circuits 102a and 102b are provided in a plurality of power conversion modules 2a and 2b in this case, respectively. The power conversion modules 2a and 2b are connected. At the same time, voltage command generation circuits 103a and 103b, comparators 104a and 104b, and switching circuits 105a and 105b are provided in the power conversion modules 2a and 2b, respectively, and reference voltage generation circuits 106a and 106b are respectively provided with detection widths. An abnormal stop circuit composed of comparators 107a and 107b and latched buffers 108a and 108b is provided.
The reference voltage generation circuits 106a and 106b generate voltages corresponding to the carrier lower limit in the power conversion modules 2a and 2b.

ここで、キャリア信号Ｃａ、Ｃｂと基準電圧発生回路１０６ａ、１０６ｂの出力を検出幅付き比較器１０７ａ、１０７ｂでそれぞれ比較し、その差が検出幅以内であればＬｏｗを、検出幅を超えていればＨｉｇｈを前記検出幅付き比較器１０７ａ、１０７ｂより出力し、ラッチ付バッファ１０８ａ、１０８ｂへそれぞれ入力する。
ラッチ付バッファ１０８ａ、１０８ｂでは同期信号Ｆ’がＨｉｇｈ→Ｌｏｗに変化するタイミングで入力信号を出力に反映し、１度でもＨｉｇｈを出力すると以後は“異常”とみなしてＨｉｇｈを出力し続ける。この様にして同期信号入力時のキャリア信号の状態が後述する図２（ｂ）のキャリア下限値＋Ｌと−Ｌに示す範囲の許容値を超えていれば異常と判断する異常検出回路を構成し、スイッチング回路１０５ａ、１０５ｂへそれぞれ接続する。 Here, the carrier signals Ca and Cb and the outputs of the reference voltage generation circuits 106a and 106b are compared by the comparators 107a and 107b with detection widths, respectively, and if the difference is within the detection width, Low is exceeded and the detection width is exceeded. For example, High is output from the comparators 107a and 107b with detection width and input to the latched buffers 108a and 108b, respectively.
In the latched buffers 108a and 108b, the input signal is reflected in the output at the timing when the synchronization signal F ′ changes from High to Low, and if High is output even once, it is regarded as “abnormal” and continues to output High. In this way, an abnormality detection circuit is formed that determines that an abnormality occurs if the state of the carrier signal when the synchronization signal is input exceeds the allowable values in the ranges shown in carrier lower limit values + L and -L in FIG. Are connected to the switching circuits 105a and 105b, respectively.

図２（ｂ）は、実施の形態２でキャリア信号発生回路１０２ａ、１０２ｂが正常な場合の動作、及び異常が起きた際の動作を示す。同図において、キャリア信号発生回路１０２ａ、１０２ｂが正常な場合、キャリア信号Ｃａ、Ｃｂは同期信号Ｆ’に同期しているために同期信号Ｆ’がＨｉｇｈ→Ｌｏｗに変化する直前のキャリア信号Ｃａ、Ｃｂの状態はキャリア下限値にほぼ等しく、検出幅付き比較器１０７ａ、１０７ｂの出力信号Ｄａ、ＤｂはＬｏｗとなる。そのため、ラッチ付バッファ１０８ａ、１０８ｂの出力信号Ｅａ、ＥｂはＬｏｗである。 FIG. 2B shows an operation when the carrier signal generation circuits 102a and 102b are normal in the second embodiment and an operation when an abnormality occurs. In the figure, when the carrier signal generation circuits 102a and 102b are normal, the carrier signals Ca and Cb are synchronized with the synchronization signal F ′, so that the carrier signal Ca and the carrier signal Ca immediately before the synchronization signal F ′ changes from High to Low. The state of Cb is almost equal to the carrier lower limit value, and the output signals Da and Db of the comparators 107a and 107b with detection width become Low. Therefore, the output signals Ea and Eb of the latched buffers 108a and 108b are Low.

次に、キャリア信号発生回路１０２ａに異常が起きて、キャリア信号Ｃａの周期が同期信号Ｆ’の周期と異なる様になると、同期信号Ｆ’がＨｉｇｈ→Ｌｏｗに変化する直前でもキャリア信号Ｃａはキャリア下限値と異なるため、比較器１０７ａの出力信号ＤａはＨｉｇｈとなり、ラッチ付バッファ１０８ａの出力信号ＥａはＨｉｇｈとなる。
そして、出力信号Ｅａ＝Ｈｉｇｈになったことにより、スイッチング回路１０５ａは“異常”と判断してスイッチング動作を停止させる。 Next, when an abnormality occurs in the carrier signal generation circuit 102a and the cycle of the carrier signal Ca becomes different from the cycle of the synchronization signal F ′, the carrier signal Ca is transmitted even immediately before the synchronization signal F ′ changes from High to Low. Since it is different from the lower limit value, the output signal Da of the comparator 107a becomes High, and the output signal Ea of the buffer with latch 108a becomes High.
Then, when the output signal Ea = High, the switching circuit 105a determines “abnormal” and stops the switching operation.

キャリア信号発生回路１０２ｂに異常が起きて、キャリア信号Ｃｂの周期が同期信号Ｆ’の周期と異なる場合にも、同様に同期信号Ｆ’がＨｉｇｈ→Ｌｏｗに変化する直前でのキャリア信号Ｃｂがキャリア下限値と異なるため、容易に異常を検出することができる。また、図２では同期信号によりキャリア下限に同期させる場合の例を示しているが、他の任意の位相にキャリアを同期させる場合にも同様に実現することができる。 Similarly, when an abnormality occurs in the carrier signal generation circuit 102b and the cycle of the carrier signal Cb is different from the cycle of the synchronization signal F ′, the carrier signal Cb immediately before the synchronization signal F ′ changes from High to Low Since it is different from the lower limit value, an abnormality can be easily detected. Further, FIG. 2 shows an example in which the synchronization signal is used to synchronize with the lower limit of the carrier. However, the same can be realized when the carrier is synchronized with another arbitrary phase.

以上のようにして、この実施の形態２では同期信号入力時のキャリア信号の状態が許容値を超えていれば異常と判断することにより、容易にキャリア異常を検出することができる。 As described above, in the second embodiment, it is possible to easily detect a carrier abnormality by determining that the carrier signal is abnormal if the state of the carrier signal when the synchronization signal is input exceeds an allowable value.

実施の形態３．
次に実施の形態３に係る電力変換装置５００ｂの構成のブロック図を図３に示す。同図において複数の電力変換モジュールこの場合３台の電力変換モジュール２ａ、２ｂ、２ｃ内にキャリア信号発生回路１０２ａ、１０２ｂ、１０２ｃをそれぞれ設けて伝送路３で前記電力変換モジュール２ａ〜２ｃ間を接続する。同時に、電力変換モジュール２ａ、２ｂ、２ｃ内に電圧指令発生回路１０３ａ、１０３ｂ、１０３ｃと、比較器１０４ａ、１０４ｂ、１０４ｃおよびスイッチング回路１０５ａ、１０５ｂ、１０５ｃをそれぞれ設けている。
また、電力変換モジュール２ａ、２ｂ、２ｃ内にそれぞれ同期信号出力回路１０１ａ、１０１ｂ、１０１ｃを設けるとともに第１の同期異常検出回路１０９ａ、１０９ｂ、１０９ｃおよび第２の同期異常検出回路１０９ｄ、１０９ｅ、１０９ｆ及び接続回路１１０ａ、１１０ｂ、１１０ｃを設けている。 Embodiment 3 FIG.
Next, FIG. 3 shows a block diagram of a configuration of power conversion device 500b according to the third embodiment. In the figure, a plurality of power conversion modules, in this case, carrier signal generation circuits 102a, 102b and 102c are provided in three power conversion modules 2a, 2b and 2c, respectively, and the power conversion modules 2a to 2c are connected by a transmission line 3. To do. At the same time, voltage command generation circuits 103a, 103b, 103c, comparators 104a, 104b, 104c, and switching circuits 105a, 105b, 105c are provided in the power conversion modules 2a, 2b, 2c, respectively.
In addition, synchronization signal output circuits 101a, 101b, and 101c are provided in the power conversion modules 2a, 2b, and 2c, respectively, and the first synchronization abnormality detection circuits 109a, 109b, and 109c and the second synchronization abnormality detection circuits 109d, 109e, and 109f are provided. In addition, connection circuits 110a, 110b, and 110c are provided.

ここで前記第１の同期異常検出回路１０９ａ、１０９ｂ、１０９ｃはそれぞれの各電力変換モジュール２ａ、２ｂ、２ｃ内における同期信号Ｆ’を監視するものである。そして第１の同期異常検出回路１０９ａはキャリア３周期の期間に前記同期信号Ｆ’が変化しない場合、“同期異常”と検出するように設定されている。同様に同期異常検出回路１０９ｂはキャリア４周期で、同期異常検出回路１０９ｃはキャリア５周期で、それぞれ“同期異常”と検出するように設定されている。
一方、第２の同期異常検出回路１０９ｄは、同期信号出力回路１０１ａの出力信号Ｆａを監視し、キャリア２周期の期間に前記同期信号Ｆａが変化しない場合、第２の同期異常検出回路１０９ｄは“同期回路異常”と検出するように設定されている。同様に、第２の同期異常検出回路１０９ｅは、同期信号出力回路１０１ｂの出力信号Ｆｂを、第２の同期異常検出回路１０９ｆは同期信号出力回路１０１ｃの出力信号Ｆｃを、それぞれ監視する。
電力変換モジュール２ａ内において、第１の同期異常検出回路１０９ａが“同期異常”を検出すると、接続回路１１０ａは同期信号出力回路１０１ａを伝送路３に接続し、第２の同期異常検出回路１０９ｄが“同期回路異常”と検出すると接続回路１１０ａは同期信号出力回路１０１ａと伝送路３を切り離す。 Here, the first synchronization abnormality detection circuits 109a, 109b, and 109c monitor the synchronization signal F ′ in each of the power conversion modules 2a, 2b, and 2c. The first synchronization abnormality detection circuit 109a is set to detect “synchronization abnormality” when the synchronization signal F ′ does not change during the period of three carrier cycles. Similarly, the synchronization abnormality detection circuit 109b is set to detect “synchronization abnormality” in four cycles of the carrier and the synchronization abnormality detection circuit 109c in five cycles of the carrier.
On the other hand, the second synchronization abnormality detection circuit 109d monitors the output signal Fa of the synchronization signal output circuit 101a. When the synchronization signal Fa does not change during the period of two carriers, the second synchronization abnormality detection circuit 109d “Synchronous circuit error” is set to be detected. Similarly, the second synchronization abnormality detection circuit 109e monitors the output signal Fb of the synchronization signal output circuit 101b, and the second synchronization abnormality detection circuit 109f monitors the output signal Fc of the synchronization signal output circuit 101c.
In the power conversion module 2a, when the first synchronization abnormality detection circuit 109a detects "synchronization abnormality", the connection circuit 110a connects the synchronization signal output circuit 101a to the transmission line 3, and the second synchronization abnormality detection circuit 109d When the “synchronization circuit abnormality” is detected, the connection circuit 110a disconnects the synchronization signal output circuit 101a from the transmission path 3.

電力変換モジュール２ｂ、２ｃ内部でも、接続回路１０１ｂ、１０１ｃを同様に動作させ、第１の同期異常検出回路１０９ｂ、１０９ｃおよび第２の同期異常検出回路１０９ｅ、１０９ｆをそれぞれの状態に応じて同期信号出力回路１０１ｂ、１０１ｃと伝送路３との接続・切り離しを行う。 Even within the power conversion modules 2b and 2c, the connection circuits 101b and 101c are operated in the same manner, and the first synchronization abnormality detection circuits 109b and 109c and the second synchronization abnormality detection circuits 109e and 109f are synchronized with each other according to their respective states. The output circuits 101b and 101c and the transmission path 3 are connected / disconnected.

図４は、この実施の形態３で、複数の電力変換モジュール２ａ、２ｂ、２ｃの内第１の電力変換モジュールに相当する電力変換モジュール２ａの同期信号出力回路１０１ａが正常な場合、および前記同期信号出力回路１０１ａが異常で、前記第１の電力変換モジュール２ａの次に設けられた同期信号出力回路１０１ｂが正常な場合のそれぞれの動作を示す。
図４において、起動直後の第１の電力変換モジュール２ａ内の同期信号出力回路１０１ａが正常な状態では、接続回路１１０ａ、１１０ｂ、１１０ｃは全て“切り離し”状態であり、各電力変換モジュールにおける同期信号Ｆ’は変化しない。ここで、各電力変換モジュールの第１の同期異常検出回路１０９ａ、１０９ｂ、１０９ｃは異常検出期間は前述したようにそれぞれ異なる様に設定されているため、同期信号Ｆ’一定の状態がキャリア３周期連続すると第１の電力変換モジュール２ａの第１の同期異常検出回路１０９ａのみが“同期異常”と認識し、接続回路１１０ａが動作して同期信号出力回路１０１ａが伝送路３に接続される。
これにより、同期信号出力回路１０１ａから出力された同期信号Ｆａが、各電力変換モジュール２ａ、２ｂ、２ｃに出力され、キャリア信号発生回路１０２ａ、１０２ｂ、１０２ｃから出力されたキャリア信号Ｃａ、Ｃｂ、Ｃｃは同期信号Ｆａに同期する。 FIG. 4 shows the third embodiment in which the synchronization signal output circuit 101a of the power conversion module 2a corresponding to the first power conversion module among the plurality of power conversion modules 2a, 2b, and 2c is normal and the synchronization. Each operation when the signal output circuit 101a is abnormal and the synchronization signal output circuit 101b provided next to the first power conversion module 2a is normal is shown.
In FIG. 4, when the synchronization signal output circuit 101a in the first power conversion module 2a immediately after startup is in a normal state, all the connection circuits 110a, 110b, and 110c are in a “disconnected” state, and the synchronization signal in each power conversion module F ′ does not change. Here, since the first synchronization abnormality detection circuits 109a, 109b, 109c of each power conversion module are set to have different abnormality detection periods as described above, the constant state of the synchronization signal F ′ is three periods of the carrier. If it continues, only the first synchronization abnormality detection circuit 109 a of the first power conversion module 2 a recognizes “synchronization abnormality”, the connection circuit 110 a operates, and the synchronization signal output circuit 101 a is connected to the transmission line 3.
As a result, the synchronization signal Fa output from the synchronization signal output circuit 101a is output to each power conversion module 2a, 2b, 2c, and the carrier signals Ca, Cb, Cc output from the carrier signal generation circuits 102a, 102b, 102c. Is synchronized with the synchronization signal Fa.

次に、同期信号出力回路１０１ａに異常が発生して、同期信号ＦａがＬｏｗ一定になりキャリア２周期以上経過すると、第２の同期異常検出回路１０９ｄは“同期回路異常”と検出し、接続回路１１０ａが動作して同期信号出力回路１０１ａと伝送路３を切り離す。
ここで、電力変換モジュール２ｂ、２ｃの接続回路１１０ｂ、１１０ｃは“切り離し”状態になっているため、各電力変換モジュールにおける同期信号Ｆ’はＬｏｗ一定になる。この状態がキャリア４周期以上連続すると、今度は第１の電力変換モジュール２ａの次に設けられた第２の電力変換モジュール２ｂに設けられた前記第１の同期異常検出回路１０９ｂが“同期異常”と認識し、接続回路１１０ｂが動作して同期信号出力回路１０１ｂが伝送路３に接続される。
これにより、第２の電力変換モジュール２ｂの同期信号出力回路１０１ｂから出力された同期信号Ｆｂが、各電力変換モジュール２ａ、２ｂ、２ｃに出力され、キャリア信号発生回路１０２ａ、１０２ｂ、１０２ｃから出力されたキャリア信号Ｃａ、Ｃｂ、Ｃｃは同期信号Ｆｂに同期する。 Next, when an abnormality occurs in the synchronization signal output circuit 101a and the synchronization signal Fa becomes low and the two or more cycles of the carrier elapse, the second synchronization abnormality detection circuit 109d detects “synchronization circuit abnormality”, and the connection circuit 110a operates to disconnect the synchronization signal output circuit 101a from the transmission path 3.
Here, since the connection circuits 110b and 110c of the power conversion modules 2b and 2c are in the “disconnected” state, the synchronization signal F ′ in each power conversion module becomes Low. If this state continues for four or more periods of the carrier, the first synchronization abnormality detection circuit 109b provided in the second power conversion module 2b provided next to the first power conversion module 2a is now "synchronous abnormality". The connection circuit 110b operates and the synchronization signal output circuit 101b is connected to the transmission line 3.
As a result, the synchronization signal Fb output from the synchronization signal output circuit 101b of the second power conversion module 2b is output to each power conversion module 2a, 2b, 2c, and output from the carrier signal generation circuits 102a, 102b, 102c. The carrier signals Ca, Cb, and Cc are synchronized with the synchronization signal Fb.

この様にして、同期信号出力回路に異常が発生しても、異常な同期信号出力回路の切り離し及び健全な同期信号出力回路の接続を行うことができるため、装置全体の信頼性を向上させることができる。また、個々の電力変換モジュール内の異常検出回路の異常検出期間を異なる値に設定しているので同期信号出力回路が同時に２台以上伝送路に接続されることを防止できるため、各同期信号出力回路の出力信号が衝突することによる不具合を防止して装置全体の信頼性を向上させることができるという効果がある。 In this way, even if an abnormality occurs in the synchronization signal output circuit, it is possible to disconnect the abnormal synchronization signal output circuit and connect the sound synchronization signal output circuit, thereby improving the reliability of the entire apparatus. Can do. In addition, since the abnormality detection period of the abnormality detection circuit in each power conversion module is set to a different value, it is possible to prevent two or more synchronization signal output circuits from being connected to the transmission line at the same time. There is an effect that it is possible to improve the reliability of the entire apparatus by preventing problems caused by collision of output signals of the circuits.

なお、図３では電力変換モジュールのみで電力変換装置を構成した例を示しているが、図１、図２の様に制御モジュールを含む構成の電力変換装置、及び制御モジュール内部にも同期信号出力回路を備えた場合でも同様に実現することができる。また、電力変換モジュールを３台の例で示したが、３台以上の複数であってもよい。 Although FIG. 3 shows an example in which the power conversion device is configured only by the power conversion module, the synchronization signal is also output inside the power conversion device including the control module as shown in FIGS. 1 and 2 and the control module. Even when a circuit is provided, the same can be realized. Moreover, although the power conversion module was shown by the example of 3 units | sets, more than 3 may be sufficient.

以上のようにして、電力変換モジュールそれぞれに、同期信号出力回路と、一定期間同期信号が入力されなければ同期信号異常と判断する異常検出回路と、接続回路を備えたことにより、同期信号出力回路に異常が発生しても、異常な同期信号出力回路の切り離し及び健全な同期信号出力回路の接続を行うことができるため、装置全体の信頼性を向上させることができる。 As described above, each of the power conversion modules includes the synchronization signal output circuit, the abnormality detection circuit that determines that the synchronization signal is abnormal if the synchronization signal is not input for a certain period, and the connection circuit. Even if an abnormality occurs, since the abnormal synchronization signal output circuit can be disconnected and the healthy synchronization signal output circuit can be connected, the reliability of the entire apparatus can be improved.

以上のようなこの発明の実施の形態１〜３は、複数の電力変換モジュールを備えた電力変換装置に利用すれば、装置全体の信頼性を向上可能である。 The first to third embodiments of the present invention as described above can improve the reliability of the entire apparatus when used in a power conversion apparatus including a plurality of power conversion modules.

この発明の実施の形態１に係る電力変換装置の構成を示すブロック図である。It is a block diagram which shows the structure of the power converter device which concerns on Embodiment 1 of this invention. この発明の実施の形態２に係る電力変換装置の構成を示すブロック図である。It is a block diagram which shows the structure of the power converter device which concerns on Embodiment 2 of this invention. この発明の実施の形態３に係る電力変換装置の構成を示すブロック図である。It is a block diagram which shows the structure of the power converter device which concerns on Embodiment 3 of this invention. この発明の実施の形態３に係る電力変換装置の動作説明図である。It is operation | movement explanatory drawing of the power converter device which concerns on Embodiment 3 of this invention.

Explanation of symbols

１制御モジュール、２ａ，２ｂ，２ｃ電力変換モジュール、３伝送路、
１０１，１０１ａ，１０１ｂ，１０１ｃ同期信号発生回路、
１０２ａ，１０２ｂ，１０２ｃキャリア信号発生回路、
１０３ａ，１０３ｂ，１０３ｃ電圧指令発生回路、
１０４ａ，１０４ｂ，１０４ｃ比較器、
１０５ａ，１０５ｂ，１０５ｃスイッチング回路、
１０６ａ，１０６ｂ基準電圧発生回路、１０７ａ，１０７ｂ検出幅付き比較器、
１０８ａ，１０８ｂラッチ付バッファ、
１０９ａ，１０９ｂ，１０９ｃ，１０９ｄ，１０９ｅ，１０９ｆ同期異常検出回路、
１１０ａ，１１０ｂ，１１０ｃ接続回路、
５００，５００ａ，５００ｂ電力変換装置、Ｆ，Ｆ’，Ｆａ，Ｆｂ，Ｆｃ同期信号。 1 control module, 2a, 2b, 2c power conversion module, 3 transmission line,
101, 101a, 101b, 101c synchronization signal generation circuit,
102a, 102b, 102c carrier signal generation circuit,
103a, 103b, 103c voltage command generation circuit,
104a, 104b, 104c comparators,
105a, 105b, 105c switching circuit,
106a, 106b reference voltage generation circuit, 107a, 107b comparator with detection width,
108a, 108b Buffer with latch,
109a, 109b, 109c, 109d, 109e, 109f Synchronization abnormality detection circuit,
110a, 110b, 110c connection circuit,
500, 500a, 500b Power converter, F, F ′, Fa, Fb, Fc Sync signal.

Claims

A power converter,
The power conversion device includes a control module and a plurality of power conversion modules connected to the control module via a transmission line,
The power conversion module includes a carrier signal generation circuit, a voltage command generation circuit, a comparator, a switching circuit , a reference voltage generation circuit, a comparator with a detection width, and a buffer with a latch. An abnormal stop circuit of the carrier signal generation circuit is provided,
The carrier signal generation circuit detects a change in the synchronization signal F ′ that is output from the synchronization signal output circuit provided in the control module and is affected by the transmission path, and synchronizes the carrier signal to an arbitrary phase. And the comparator compares the carrier signal with the output signal of the voltage command generation circuit, the result is output to the switching circuit, and the carrier signal output from the carrier signal generation circuit and The comparator with the detection width compares the output of the reference voltage generation circuit, and outputs an abnormal signal to the latched buffer when the difference is greater than or equal to an allowable value, and the latched buffer outputs the synchronization signal F ′. When an abnormality signal output from the comparator with a detection width is input at a change timing, the carrier signal generation circuit abnormality detection signal is sent to the switching circuit. Outputs, the switching circuit is a power conversion apparatus characterized by stopping the switching operation.

A power conversion device comprising a plurality of power conversion modules connected via a transmission line,
The power conversion module includes a synchronization signal output circuit, a carrier signal generation circuit, a voltage command generation circuit, a comparator, a switching circuit, a first synchronization abnormality detection circuit, a second synchronization abnormality detection circuit, and a connection Circuit is provided,
The first synchronization abnormality detection circuit outputs a synchronization abnormality when the synchronization signal F ′ output from the synchronization signal output circuit and affected by the transmission path does not change within the abnormality detection period. The abnormality detection period is set to be different for each of the plurality of power conversion modules, and the second synchronization abnormality detection circuit is configured so that the output of the synchronization signal output circuit exceeds a predetermined detection period. When the change does not change, the synchronization signal output circuit outputs an abnormality, and the connection circuit connects the synchronization signal output circuit to the transmission line by the output of the first synchronization abnormality detection circuit, The synchronization signal output circuit is separated from the transmission line by the output of the second synchronization abnormality detection circuit, and when the synchronization signal output circuit is normal, the detection period with the shortest abnormality detection period Only the synchronization signal output circuit in the power conversion module provided with the first synchronization abnormality detection circuit set in between is connected to the transmission line via the connection circuit, and the output is the power Output to the conversion module, each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized with an arbitrary phase, and the comparator outputs the carrier signal and the voltage command generation circuit. And the result is output to the switching circuit, and when the second synchronization abnormality detection circuit detects an abnormality in the synchronization signal output circuit, the connection circuit detects the synchronization signal output circuit. When this state is disconnected from the transmission line and this state continues beyond the second shortest detection period after the shortest abnormality detection period, this detection period is set. The synchronization signal output circuit in the power conversion module in which the second synchronization abnormality detection circuit is provided is connected to the transmission circuit via the connection circuit, and an output thereof is connected to each power conversion module. Each carrier signal generation circuit detects a change in the synchronization signal F ′, outputs a carrier signal synchronized with an arbitrary phase, and outputs the carrier signal and the output signal of the voltage command generation circuit by the comparator. Are compared, and the result is output to the switching circuit. Similarly, when an abnormality occurs in the synchronous signal output circuit, the power conversion module sequentially approximates based on the length of the set abnormality detection period. Is switched to the synchronization signal output circuit, and the output is output to each power conversion module, and each carrier signal generation circuit detects a change in the synchronization signal F ′. A carrier signal synchronized with an arbitrary phase is output, the carrier signal is compared with the output signal of the voltage command generation circuit by the comparator, and the result is output to the switching circuit. Power conversion device.