Kalp hareketleri kullanarak piezoelektrik enerji üretimi

ABSTRACTPIEZOELECTRIC POWER GENERATIONUSING HEART MOTIONOnur AfacanM.S. in Electrical and Electronics EngineeringSupervisor: Prof. Dr. Ergin AtalarSeptember 2006The presence of pacemakers and implantable cardioverter-defibrillators (ICD) isconsidered historically a contraindication to magnetic resonance (MR) imaging.Main reason behind this contraindication is the current induced on the pacingleads during the MRI examination which may damage the cardiac tissues byheating or the pulse generator of the pacemaker with a reverse current. In thisthesis an approach towards the solution of this problem is stated. It has beenshown in previous work that replacing the pacing leads with fiber-optic cablesminimizes the current induced on the leads. Drawback of this system is theincrease in the power consumption of the pacemaker because of the fiber-opticcables and also necessity of an additional pulse generator circuitry near the heart.In this thesis, feasibility of using a piezoelectric power generator for compensatingthe increased power consumption is investigated. A novel piezoelectric geometryincreasing the effective length in a given volume is designed. With this devicethe resonance frequency of the generator was decreased and the power outputfor a given volume is increased compared to standard rectangular piezoelectricbimorphs. When connected to a simple heart phantom the novel design produced2.83 microwatts power whereas the standard rectangular bimorphs produced lessiiithan 1 microwatts. Although the output power is increased with the novel design,it was not sufficient to power a pulse generator circuitry that will be used to pacethe heart.Keywords: Piezoelectric Power Generation, Vibrations, MRI, Pacemaker, MRIinterferenceiv