To inexpensively and accurately detect on-operation malfunction (opening of a relay contact) of n relays.
A power conversion device comprises: a forward converter for rectifying AC voltage of an AC power supply to convert to DC voltage; a DC intermediate circuit having a smoothing capacitor for smoothing the DC voltage of the forward converter; a current-limiting circuit for suppressing charge current to the smoothing capacitor in the DC intermediate circuit; a voltage detection circuit for detecting voltage of the DC intermediate circuit; an inverse converter for converting the DC voltage of the forward converter to AC voltage; n temperature detection elements which are arranged on a circuit board connected to a terminal corresponding to contact parts of n relays connected in parallel to a resistance of the current-limiting circuit, and detect temperature of each of the n relays; and a control unit for detecting that any of the n relays is abnormal, on the basis of a detection result of each of the temperature detection elements. Detecting temperature differences among the n temperature detection elements makes it possible to detect abnormality of the relays.
| JP01164225 | MOTOR WINDING TEMPERATURE DETECTOR |
| WO/2014/132571 | ABNORMALITY DETECTION AND PROTECTION CIRCUIT |
| JPH10285802 | POWER DEVICE |
HIRAGA MASAHIRO
HIROTA MASAYUKI
ARAO YUSUKE
TANAKA MAKOTO
| JPH02221878A | 1990-09-04 | |||
| JPH0556552A | 1993-03-05 | |||
| JP2006041407A | 2006-02-09 | |||
| JP2008135321A | 2008-06-12 | |||
| JP2008206280A | 2008-09-04 | |||
| JP2013024718A | 2013-02-04 | |||
| JPH02221878A | 1990-09-04 | |||
| JPH0556552A | 1993-03-05 | |||
| JP2006041407A | 2006-02-09 | |||
| JP2008135321A | 2008-06-12 | |||
| JP2008206280A | 2008-09-04 | |||
| JP2013024718A | 2013-02-04 |
| US20050275993A1 | 2005-12-15 | |||
| US20050275993A1 | 2005-12-15 |
戸田 裕二
岩崎 重美