Control strategy to achieve minimum / zero input current ripple for the interleaved boost converter in Photovoltaic / Fuel Cell Power Conditioning System

It is desirable to have low input current ripple for Photovoltaic / Fuel Cell Power Conditioning System (PCS). A typical input filter could be bulky and costly in order to decrease the input current ripple of the dc-dc converter to satisfy the requirement of low current ripple. This paper proposes a new control approach of adjusting the active phase number and switching frequency to achieve the low or zero input current ripples in the interleaved boost converter. Therefore the input filter is not needed in steady-state. Comparing with existing common solutions, this solution features a lower cost, more compact, better current ripple performance and higher reliability. Simulation and experimental results show that the input current ripples can be greatly decreased with this strategy. The principle of this control approach is also valid for other common interleaved dc-dc topologies.