High-gain DC-DC Converter with Ultra-low Input Voltage*

Energy-harvesting technologies enable the extraction of energy from environmental sources characterized by extremely low voltages. A high-gain DC-DC converter with an ultralow input voltage is necessary for voltage conversion to supply energy to sensors, batteries, and other devices. However, existing ultra-low-voltage boost converters typically exhibit limited output power, posing significant challenges in fully utilizing the available energy, particularly in applications such as high-voltage direct-current (HVDC) transmission line voltage-difference energy harvesting. To maximize the harvested energy, this study proposes a high-gain DC-DC converter designed for operation with ultra-low input voltage. The proposed converter utilizes a hybrid inductor-switch-capacitor (LSC) boost network, which offers advantages such as high voltage gain, increased output power, and straightforward control mechanisms. Experimental findings indicate that the converter achieves output power ranging from 10 to 210 mW with input voltages between 100 and 300 mV, delivering an output voltage of 5 V. This performance surpasses that of existing ultra-low-voltage boosting methods, providing a more effective solution for energy-harvesting applications.