First windings of a first common mode transformer and second windings of a second common mode transformer are connected in series via connection lines. The windings are connected to an AC power supply via connection lines. The first windings are connected to a three-phase motor via connection lines, a converter, and an inverter. High-frequency leakage currents flowing in the connection lines are detected as a common mode voltage by a winding for common mode voltage detection. An output voltage is inputted via a filter to a voltage amplifier unit that amplifies the output voltage, and the amplified voltage is applied to a winding via a capacitor in substantially a same direction as a direction of the common mode voltage. As a result, leakage currents are reduced by induced voltages on the windings.

Title
Leakage current reducing apparatus
Application Number
13/636209
Publication Number
20130010506
Application Date
April 1, 2011
Publication Date
January 10, 2013
Inventor
Satoshi Azuma
Takuya Sakai
Assignee
Mitsubishi Electric Corporation
IPC
H02M 05/458
H02M 07/537
H02M 07/06
H03B 19/00
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