The Master’s thesis in the Technical College of Engineering / Mosul, specializing in electrical power technology engineering, examined the design and implementation of a resonant transformer (DC-DC) working in a grid-connected photovoltaic system.

The thesis presented by the student “Mohannad Khaled Mohamed” dealt with the implementation of analysis and design procedures for grid integration of photovoltaic systems based on the LLC type DC-DC resonant converter, which is more suitable for these systems in terms of having a wide gain voltage range as well as wide load changes.

The message showed that the DC-DC resonant transformer of the LLC type achieves an efficiency of more than 95%, as this efficiency was achieved through the use of the Zero Voltage Switching (ZVS) technology to reduce losses in the switches, as well as the use of the (FHA) method that takes into account the basic harmonic Only that eliminates all other harmonics.

The thesis recommended finding the most appropriate solutions and methods in the design of the resonant transformer circuit and ways to control it, as well as the way to obtain the highest capacity from solar cells through a comparative study between the perturbation and successive (P&O) algorithm and the incremental conduction (INC) algorithm, giving the (P&O) algorithm the best efficiency and the Take it and apply it in practice and also get an efficiency of 98.3%.

The discussion committee consisted of:

1. Assistant Professor Dr. Rakan Khalil Antar/Chairman
2. Assistant Professor Dr. Omar Hazem Muhammad / Member
3. The teacher, Dr. Saad Inad Muhammad / member
4. Assistant Professor Dr. Ahmed Attia Alo / member and supervisor