Kabushiki Kaisha Yaskawa Denki

Ryuji Suenaga

Yozo Ueda

Eiji Yamamoto

Eiji Watanabe

Taisuke Katayama

Kazuhiro Umeo

Kenichi Imanishi

A series-connected multi-level power conversion device according to an aspect of embodiments includes a multi-winding transformer and a power conversion unit. The multi-winding transformer has a relationship that n secondary windings respectively connected to n single-phase power converters in the same output phase have a voltage phase difference of 60/n degrees and a relationship that the m secondary windings respectively connected to the m single-phase power converters corresponding to the m output phases have a voltage phase difference of 60/m degrees.

Series connected multi-level power conversion device

A control apparatus for a series-connected multi-level matrix converter includes each voltage commanding device provided for each of single-phase matrix converters to generate a voltage reference to each of the single-phase matrix converters. The series-connected multi-level matrix converter includes the single-phase matrix converters. Each of the single-phase matrix converters includes a snubber circuit and a DC voltage detecting section configured to detect a DC voltage of the snubber circuit to output a DC voltage detection value. ADC over-voltage detector is configured to output a DC over-voltage signal when the DC voltage detection value exceeds a set voltage value. A voltage modifying device is, when the DC over-voltage signal is outputted, configured to decrease the voltage reference to a corresponding single-phase matrix converter among the single-phase matrix converters based on a deviation between the DC voltage detection value and the set voltage value.

Control apparatus for matrix converter

A control device for a matrix converter includes an input voltage detector, an output current detector, a pulse width modulator, and an input voltage command calculator. The input voltage detector is configured to detect an input voltage of the matrix converter. The output current detector is configured to detect an output current of the matrix converter. The pulse width modulator is configured to generate a PWM pulse command signal by using the input voltage, the output current, and an output line voltage command. The input voltage command calculator is configured to calculate an input voltage command of the matrix converter.

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Fukuoka, Japan

Ryuji Suenaga