Toshiba Mitsubishi-electric Industrial Systems Corporation

Tmeic Corporation

Haruyuki Yamaguchi

Chikara Morito

Shunsuke Tobayashi

Kenshi Takao

Kazuhide Kaneko

Shinya Kawai

A drive system () drives a multi-phase AC motor () having a plurality of windings. The drive system () includes a first power converter (U), a second power converter (V), a first conversion controller (U), and a second conversion controller (V). The first power converter (U) causes a current to flow through a winding of a first phase of the multi-phase AC motor (). The second power converter (V) causes a current to flow through a winding of a second phase of the multi-phase AC motor (). The first conversion controller (U) decides on either a three-level phase voltage waveform or a five-level phase voltage waveform on the basis of setting information for designating a type of phase voltage waveform and controls the first power converter (U) so that the decided phase voltage waveform is output from the first power converter (U). The second conversion controller (V) controls the second power converter (V) so that a phase voltage waveform having the same type as the phase voltage waveform of the first power converter (U) is output from the second power converter (V) on the basis of the setting information for designating the type of phase voltage waveform.

Drive system and control device for drive system

According to an embodiment, a capacitor diagnosis device includes a sensor, a frequency spectrum analysis unit, a frequency component extraction unit, and a diagnosis processing unit. The sensor detects a physical quantity that changes with an current flowing through a capacitor in a power conversion unit (PCU) for converting DC power smoothed by the capacitor connected in parallel to DC link(s) into AC power according to a power running operation. The frequency spectrum analysis unit generates a frequency spectrum based on a detection result of the sensor detected during the power running operation of the PCU. The frequency component extraction unit extracts a component of a specific frequency band related to a frequency depending on a configuration of the PCU based on the frequency spectrum. The diagnosis processing unit diagnoses a state of the capacitor based on at least a magnitude of the extracted component of the specific frequency band.

Capacitor diagnosis device and capacitor diagnosis method

A power conversion device includes first to fourth switching elements, and first to eighth diodes. The first to fourth diodes are electrically connected in inverse parallel to the first to fourth switching elements, respectively. The seventh diode is electrically connected in parallel to the second diode. The eighth diode is electrically connected in parallel to the third diode. The second diode is housed in a first package. The seventh diode is housed in a second package, which is different from the first package, and which does not include the switching elements. The eighth diode is housed in the second package, or alternatively, the eighth diode is housed in another package, which is different from the first package and the second package, and which does not include the switching elements.

Power conversion device of a neutral point clamp type

A power converter according to an embodiment is provided with first to fourth modules, first and second clamp diodes, and first and second buses. The first bus has a first main portion and a first standing portion provided in the first main portion. The first main portion electrically connects the first switching module and the second switching module, and is electrically connected to the first clamp diode. The second bus has a second main portion and a second standing portion provided in the second main portion. The second main portion electrically connects the third switching module and the fourth switching module, and is electrically connected to the second clamp diode. The second standing portion faces the first standing portion.

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Tokyo, Japan

Haruyuki Yamaguchi