A feedback-type Common Mode Active Filter for Vehicular Induction Motor Drives

A common mode (CM) EMI active filter for automotive induction motor drives is proposed. The active filter is useful in compensating the CM voltage at the motor input, allowing an increase of the drive reliability and a reduction of the leakage high frequency CM currents which affect the vehicle Electromagnetic Compatibility (EMC). The active filter is based on a feedback-action and it is realized using linear amplifiers. These features lead to an increased efficiency and compactness. The system analysis and its experimental implementation are presented.