A zero input current ripple boost converter for fuel cell applications by using a mirror ripple circuit

In this paper, a ripple mirror (RM) technique is proposed to achieve zero ripple condition. By choosing a boost converter as an illustrative example, the corresponding ripple mirror circuit is proposed where the average output voltage serves as the input of the RM circuit and the corresponding mirror control signal is the same as that of the boost converter. To avoid circulating current, a blocking capacitor is inserted between the RM circuit and the output of the boost converter. It is found that, by adding this low power RM circuit, the zero input ripple condition of the boost converter can be achieved rather easily. This characteristic is especially suitable for applying to fuel cell applications where the fuel cell stack current ripple is crucial to its life time and operating efficiency.