A PWM method reducing harmonics of two interleaved converters

This paper proposes a PWM method reducing harmonics of two interleaved converters at twice the switching frequency region. If harmonics at twice the switching frequency region can be reduced by the PWM method, the size of filter interfacing the grid and converter would be reduced. Based on Fourier series of phase voltage in every switching period, offset voltage for PWM minimizing harmonics at twice the switching frequency region can be calculated in real time. With the proposed PWM, the size and volume of inductive filters of two interleaved parallel converters can be shrunken conspicuously. Effectiveness of the proposed method is verified by the computer simulation and experimental results. The maximum harmonic at twice the switching frequency region has been reduced by 58% at modulation index 0.8.