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.

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