Ortamdaki mekanik enerjiyi elektrik enerjisine çeviren kapasitör tabanlı devre tasarımı

Today miniature stand-alone systems highly benefit from the improvements in ICtechnology. Shrinking dimensions to submicron technologies and reduced powerconsumption in the order of nano-watts open possibilities for new power applications.Such systems demand integrated, long lasting micro energy sources, and at that powerlevel, ambient energy scavenging arises as an alternative solution, as energy harvestingunits can be integrated conveniently through MEMS(micro electromechanical systems)technology.In this thesis a novel generator design with electrostatic approach is presented. Thegenerator creates new electrical charge, thus it can be used to recharge a reservoir. It iscomposed of variable capacitors and switches. As it does not employ inductivecomponents, it is suitable for environments in which magnetic fields should be avoided.The design is further improved to overcome the restriction on the achievable electrostaticfield given the dimensions and voltage level. A third electret with permanent charge isembedded in between the plates of the capacitor creating extra field inside the capacitorat the same potential. On the mechanical side, more work is done against increasedelectrostatic force; and on the electrical side more charge accumulation and a greatercharge gain is achieved.The system is simulated using PSpice and the results are consistent with thetheoretical expectations. An experiment utilizing macro elements is also carried out with81 percent efficiency. For micro applications, low voltage sources should be used andthis decreases power gain. The electret idea may solve the problem, and one othersolution is to increase the maximum capacitance through new capacitor designs andmaking use of microfluidics technology.Keywords: Self-powered systems, mechanical-to-electrical energy conversion,electrostatic energy conversion, variable capacitors.