Discontinuous PWM Modulation for Active Power Filters Operating in Disturbed Environments

Active power filters (APFs) are power converters able to compensate for the distorted current components injected into the mains by non-linear loads. To reduce the APF switching losses and thus to allow using higher switching frequencies, discontinuous pulse-width modulation (DPWM) techniques have been developed in the literature. However, the DPWM techniques applied to APFs are highly sensitive to the high frequency disturbances on the power lines. Therefore, this paper proposes a dedicated discontinuous modulation technique for APFs installed in disturbed environments, able to minimize the switching losses for any operating condition. The proposed solution has been experimentally validated on a 100 kVA 2-level APF inverter compensating a regenerative system used for the final functional test of industrial inverters at the end of the production line.