Low Voltage and Low Power Self-Startup Oscillator-Driven Boost Converter for Thermoelectric Generator Operating at Low Temperature

This work describes a thermoelectric generator (TEG) powered self-operating low voltage efficient dc-dc boost converter. TEG produces low output voltage while operating at low temperatures, making it incapable of directly powering any sensors. As a result, the core of such TEG-based self-powered applications is a low voltage self-startup dc-dc boost converter. This study proposes a dc-dc boost converter driven by a discrete component-based inductive and conductive coupling transformer oscillator. The oscillator circuit self-start at 17 mV at an input power of 8.87 mu W. The dc-dc boost converter self-starts up at input voltage of 18 mV with input power of 64 mu W. The proposed variable resistance based maximum power point tracking (MPPT), and output voltage control technique makes the converter simple, efficient, and cost-effective. At minimum 36 mV of TEG open-circuit voltage and a power of 67.6 mu W the circuit can perform MPPT operation. The peak efficiency of 74.5% is exhibited by dc-dc boost converter at an input voltage of 60 mV with output voltage of 2.78 V and power of 3.42 $\text{mW}$. The decent efficiency, output voltage, and power of dc-dc boost converter at low input voltage makes the present development a potential power source for self-powered wireless sensors applications.