An Efficient Active LC Snubber for Forward Converters

An efficient active LC snubber for forward converters is proposed in this paper. The proposed active LC snubber can be used to reset transformer and suppress switching surge. Further, by storing surge energy in the proposed active LC snubber and then releasing it to the flyback auxiliary output, the converter can achieve high efficiency. For a forward converter with active LC snubber, 91.02%, the maximum output efficiency can be obtained. Because of the high performance on surge suppression and energy recovery, experimental results show that the output efficiency of this proposed converter is higher than that of active-clamped-based converters. Furthermore, for a synchronous rectification forward converter with this active LC snubber, the maximum output efficiency can be further raised to 94.72%.

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