College of Engineering

A master thesis was discussed in Department of Electrical Engineering / College of Engineering / University of Mosul entitled “Efficiency Enhancement of Switched Capacitor Convertor with Variable Gain” submitted by postgraduate student (Sara Khalid Natheer), supervised by Dr. Mohamad N. Abdul Kadiron Wednesday, Dec. 22, 2021.The thesis aims to realize the maximum number of no-load voltages of a given converter circuit. The modular flying capacitor converter design has been adopted and controlled with multiple operation phases per cycle.A voltage level representation diagram has been proposed to show the possible output voltage levels. After specifying the feasible levels of the capacitor voltages, new values of the no-load voltages has been introduced that led to maximum number of no-load voltages distributed over the entire range of output voltages. Analysis have been conducted to derive the expressions of the converter’s equivalent resistance.Simulation results show that for a three-capacitor converter, the number of gain levels has been increased by about 61% compared to nearest comparable study. It has been also shown that the converter efficiency is around 97.5% when operating the converter to approximate the reference voltage to the converter’s next higher voltage. The results also show that with closed loop control, the SCC produces the reference voltage precisely.