An MPPT-Based Boost Converter with Irridiance-Aware Frequency Selection and Digital ZCS Control for Solar Energy Harvesting

This paper presents a solar energy harvesting circuit based on a boost converter. An irradiance-aware frequency selection (IAFS) scheme collaborating with maximum power point tracking (MPPT) is implemented to improve transmission efficiency. By adopting successive approximation register (SAR), the MPPT control can reach the maximum power point only in several times of comparison. Additionally, low-power digital zero-current-switching (ZCS) technique is proposed to ensure high conversion efficiency. The propose converter is implemented in 180nm CMOS process. The simulation results shows that the ZCS control accuracy reached 98% at 356mV input voltage and the peak power efficiency reached 92 % with 380m V input voltage.