Abstract:

In order to solve the problem of voltage spikes and increased voltage stress caused by the coupling inductance gain unit in the DC/DC circuit, a novel active clamp bidirectional large ratio DC/DC circuit is proposed.The proposed circuit not only realizes a large proportion voltage transformation, but also effectively absorbs the leakage energy of the coupling inductance by using the active clamp circuit, thereby the voltage stress of the power switching transistor is reduced. To verify the effectiveness of the circuit, an experimental prototype with a low-voltage side of 48 V, a high-voltage side of 400 V and a power of 200 W is designed. The experimental results show that the proposed circuit can successfully achieve a large proportion voltage transformation and reduce the voltage stress of the power switching device. The feasibility and effectiveness of the circuit design is verified. New ideas and methods for the design of DC/DC circuits are provided.

Key words: active clamp, bidirectional large ratio, DC/DC circuit, voltage stress