Reduction of Inductive Losses in Electric Vehicle Wireless Charging through Resonant Coupling

The growing awareness about sustainability and environmental concerns are accelerating the adoption of electric vehicles. They play a promising role due to their potential to significantly reduce greenhouse gas emissions, improve air quality and lessen reliance on fossil fuels. However, one of the primary concerns for potential buyers is the charging process and infrastructure. Traditional wired charging systems for electric vehicles face limitations such as user inconvenience, wear and tear of connectors and challenges in automation. As a solution, wireless electric vehicle charging has emerged, offering a more user-friendly, automated and contactless method of charging by eliminating the need for physical connectors. Wireless charging can be implemented through various approaches, primarily including inductive and resonant methods. Inductive charging suffers from relatively low efficiency due to higher energy losses during transmission. On the other hand, resonant coupling significantly improves efficiency by using electromagnetic resonance to transfer power more effectively over short distances. This method minimizes energy loss and enhances charging efficiency. This paper mainly focuses on designing and implementing a resonant coupling system using series capacitance for achieving resonance, instead of a traditional frequency oscillator. This approach simplifies the circuitry and has shown promising results in maintaining high efficiency. Investigations have been conducted by aligning the transmitter and receiver coils at various distances and load conditions to evaluate power transfer efficiency, thermal behavior and charging time. The system is also assessed for misalignment tolerance and electromagnetic safety. It reduced energy losses and maintained reasonable charging times, making it a viable alternative to conventional wired and inductive charging methods. The results observed that resonant coupling with series capacitance provides efficient and stable wireless power transfer and demonstrated the potential for resonant wireless power transfer systems to support the next generation of electric vehicle infrastructure.