Low input current ripple Battery Charging Regulator based on coupled-inductor

As shortcomings of traditional nonisolation step-down Battery Charging Regulator (BCR), a fourth-order converter known as Superbuck is studied in this paper, and the optimality of Superbuck is the continuity of both the input current and the output current. So the impact on input power is reduced using Superbuck topology, and the influence of a voltage spike of a semiconductor due to circuit parasitic inductance is avoided. Based on Superbuck topology and coupled-inductor technology, low input current ripple BCR in which peak-current-mode (PCM) control is applied is designed in this paper. According to the theoretical study, a prototype of BCR input current ripple, which is about 50% less than that of the discrete-inductor Superbuck is made, and the design requirements are all met.