| 摘要 |
PROBLEM TO BE SOLVED: To reduce leakage current which flowed into a line, up to a motor. SOLUTION: A motor is set to a six-phase motor, consisting of two coil winding W1 and W2 whose phases differ by 180 deg., an inverter is set to two sets of three-phase inverters 11 and 12 that are driven by a PWM pattern where on/off change to the opposite, the inverters 11 and 12 are connected to the motor coil winding W1 and W2 by L-C-L noise filters A1 and A2, and the two sets of inverters 11 and 12 are connected from the point between inductance L1 at the inverter side of the noise filters A1 and A2 and the motor coil winding W1 and W2 by a capacitor C12. Since the higher harmonic current of the two PWM patterns is set at opposite polarities, leakage current is canceled and no leakage current exist outside the motor (prior art). The harmonic current flows to the core part of the motor via a floating capacity. The harmonic current is rejected by the noise filters A1 and A2 and at the same time is made to bypass by the capacitor C12. |
