Reza BARZEGARKHOO (Islamic Republic of Iran)

Reza’s research is on power electronics to optimise the transfer of energy from solar power systems to the power grid. He is developing a new concept of transformer-less grid-tied multilevel voltage source inverters. His aim is to minimise the size and cost of inverters by integrating the entire power conversion process into a single power processing stage.

PhD Student in Electrical Engineering at University of Technology Sydney, Australia

Research focus: transformer-less grid-tied DC-AC power electronics converters suitable for single and three-phase renewable energy-based applications

Power electronics is a key driver in the development of sustainable energy. The challenge in the coming years is to develop new technologies at the lowest possible cost, size, and weight for both existing and new applications. Reza’s area of research is the development of such power electronics.

Power electronics are needed to connect renewable energy sources to the power grid. The output of solar panels is direct current (DC). To be able to feed direct current into the existing power grid, it must be converted into alternating current (AC). Reza has developed several types of inverters specifically for this purpose in recent years. The focus of his Master’s study was on multi-level voltage source inverters (MLVSI). He has developed several types of MLVSIs with remarkable features such as a voltage boosting feature within a single power processing stage, a reduced number of active and passive components, and a single DC power source required.

To maximise the energy output of a solar array with a string of panels under all conditions and to transfer their energy to the grid, the design and control of a dedicated front-end DC-DC converter associated with an inverter stage is needed. The role of this converter is to capture the maximum available power of solar panels and to enhance the DC voltage to meet the peak voltage of the grid. Then, the inverter stage must convert this enhanced DC-link voltage to an AC voltage waveform to inject the power into the grid. Each of these power processing stages requires a sophisticated design and control strategy. Reza’s goal is to optimise this process by efficiently applying a single-stage DC-AC boost inverter, with several additional notable features. Each of these features can significantly improve the performance of the entire energy conversion system at a lower cost and reasonable volume. To achieve this goal, he will use broadband transistors based on silicon carbide or gallium nitride with a multi-level transfomerless inverter concept. This would improve the power density and power quality of the system while attaining high overall efficiency.

The jury appreciated the practical applicability of Reza’s work as an engineer in the field of renewable energy systems alongside his academic merits. His current research and work center around improving the usability of electricity from solar modules by reducing losses when feeding it into the grid.

The research of Reza mainly contributes to the Sustainable Development Goals 7, 8, 9, 11, 12:

Take a look at this video that briefly introduces Reza and his research: