Efficiency improvement for SR forward converters with LC snubber

Design and Realization of an Isolated DC-DC Converter with Regenerative Snubber circuit using Tertiary Winding Transformer

“…In forward converter topology described in [3], without utilization of a active switch, just by the use of the snubber circuit in the primary side, efficiency has been improved. The converter has an output for 40 W with a maximum efficiency of 91% producing 3 V and 4 A at the output which is best suitable for telecommunication systems.…”

Zero‐current transition single‐ended forward converter

“…In [10][11][12][13][14][15], the lossless snubbers (LLSs) are introduced to achieve soft-switching conditions and to reduce the high-voltage spikes across the switch. The LLS topology usually consists of a capacitor, an inductor, and two diodes to recycle the leakage inductor energy [10,11]. As the switch is turned off, the leakage inductor energy is discharged into a snubber capacitor and then by resonance between the snubber capacitor and the snubber inductor, the absorbed energy in the capacitor is recycled to voltage source and load.…”

“…However, (i) the tertiary reset winding, (ii) high‐voltage spikes across power switch and rectifier diode due to resonant between parasitic capacitors and transformer leakage inductance, (iii) hard switching, which cause losses and electromagnetic interference (EMI), and (iv) reversing the recovery problems of output diodes is the main drawback of this converter. To solve these problems, some techniques are proposed in [1–23].…”

“…In [10–15], the lossless snubbers (LLSs) are introduced to achieve soft‐switching conditions and to reduce the high‐voltage spikes across the switch. The LLS topology usually consists of a capacitor, an inductor, and two diodes to recycle the leakage inductor energy [10, 11].…”

“…In [12], the discrete snubber inductor is removed and a tertiary winding on the core of the transformer is employed. The discrete snubber inductor has improved the efficiency of converters in [10, 11]. In [13], reverse recovery problems of output diodes are improved by an additional LLS circuit on the secondary side of the transformer.…”