Stability and dynamic response improvement of flyback DC-DC converter by a novel control scheme

In the conventional flyback DC-DC converter, the frequency bandwidth of the open-loop transfer function is less than the forward converter because this transfer function has a right-half-plane zero (RHPZ). In addition, a sudden decrease of output voltage called "jumping phenomenon" appears due to internal parasitic resistances when the duty ratio becomes close to the unity. This paper proposes a novel flyback topology and its control scheme, where the above disadvantages are eliminated while the circuit simplicity is maintained, and furthermore confirms the improvement of its dynamic response and stability analytically and experimentally.