Actively clamped flyback (ACF) converters, disclosed more than 30 years ago, have been again in the spotlight for a few years as an answer to the demand of higher power density ac-dc adapters and chargers for portable equipment such as laptop and tablet PC. Noncomplementary control, an alternative emerged about one decade ago to the traditional complementary control, has improved ACF’s performance by reducing the power loss associated to the reverse current conduction occurring during the off time of the main power switch. However, this new control has also brought some issues related to converter operation in case of a short circuit at the output. These issues have not been highlighted in the existing literature and the technique proposed in this paper solves them with just a little extra complexity and requiring very few additional external parts.
