A two-stage dc-dc converter with high voltage gain and reduced current ripple for efficient PV energy harvesting

PV systems require a dc-dc converter to operate at the maximum power point (MPP). However, switching based operation of these converters causes ripple current. This ripple current causes a voltage ripple due to the I-V characteristics of the PV panel. Both current and voltage ripple lead to power ripple and reduce the average energy extracted from the PV system. In this study, a two-stage boost converter (PTS-BC) topology is designed. The first stage, configured as an interleaved TP-BC fixed at [Formula: see text], drastically suppresses the input current ripple, while the second stage, operating as a conventional SP-BC, regulates the output voltage. The key novelty of this architecture stems from the use of dedicated stages for ripple cancellation and voltage regulation, thereby ensuring ripple-free PV input current across the entire duty range without requiring bulky input capacitors. The design has been validated through simulations and experimental studies performed on a 450 W PV prototype system. Within the examined operating range, duty cycle (D) changes from 10% to 80%, the PTS-BC provides a 12% and a 17% ripple reduction in input current ripple and power ripple, respectively, compared to conventional converters such as single phase boost converter (SP-BC), two phase boost converter (TP-BC), etc. In addition, PTS-BC requires significantly lower D than SP-BC and TP-BC for the same output voltage, thereby reducing conduction losses and voltage stress on switching devices in a two-stage configuration. The PTS-BC reaches a peak efficiency of approximately 98%, representing improvements of about 0.7% and 1.6% over the TP-BC and SP-BC, respectively. These results confirm that the proposed topology offers superior energy conversion performance and makes it a strong candidate for high-performance PV systems that require low input ripple and high efficiency.