INVESTIGATION AND CONTROL ASPECTS OF SOME DC-DC CONVERTERS WITH EV INTEGRATION

Abstract

As more and more people around the world use electric cars (EVs) as a more environmentally friendly way to get around, it becomes harder to keep the power grid stable. As more people start using electric vehicles (EVs), large-scale integration might cause problems with voltage drops, phase imbalances, and overloading in the grid infrastructure. In addition, changes in grid voltage and current might make EV charging operations less efficient and less reliable. This thesis suggests an intelligent bidirectional EV charging system that will help solve these problems while making sure that energy flows smoothly between the grid and EV batteries. The suggested system has two main converters: one that converts AC to DC on the grid side and one that converts DC to AC on the EV battery side. A second-order generalized integrator (SOGI)-based technique controls the AC-DC converter. This separates the basic current components from the harmonic distortions, making sure that the power flows in a sinusoidal way. The DC-DC converter uses a constant current charging algorithm to effectively control the battery's voltage and current while it is charging and discharging. These converters work together to create a strong way to transfer energy. They can switch between grid-to-vehicle (G2V) and vehicle-to-grid (V2G) modes while keeping the system stable even when the grid circumstances change. A lot of simulations with different situations, such as harmonics injection, load changes, and short-term disruptions, to see how well the system works. The results show that the SOGI-based control works well to stop distortions caused by the grid from spreading into charging and discharging currents. The technology also does a great job of regulating voltage, keeping the DC link constant even when the grid supply changes. The bidirectional DC-DC converter smoothly switches between buck and boost modes, making sure that power flows in both ways without harming the battery. The results of this study show that an enhanced EV charging architecture is possible and will improve the stability of the grid while also improving the performance of EV batteries.