ELECTRET-BASED ENERGY HARVESTING FROM VIBRATION

Tire pressure monitoring system (TPMS) has become a standard safety feature for modem automobiles. It monitors the tire pressure of the equipped vehicles wirelessly, to ensure safety of its driver and passengers. Obviously, such wireless device require a power supply to function and battery has been the source of power. An energy harvesting is becoming popular as an alternative power source for such application. Among the renewable energy sources present, vibration energy is the most versatile and ubiquitously available in the target environment. To convert vibration into electrical, an electrostatic transduction mechanism is adopted, due to ease of integration into the micro-system. However, electrostatic energy harvester requires additional charge pump to function. To overcome the drawback, an electret-based vibration energy harvesting device ( e VEH) is developed. This thesis presents new techniques to develop the electret-based energy harvester device; the electrode geometry, the variable capacitor topology and the electret material.