Time-domain design for misalignment-tolerant dynamic wireless charging

Wireless power transfer (WPT) offers a safer and more convenient alternative to traditional charging methods. In the automotive sector, dynamic WPT presents a promising solution by reducing battery size and enhancing vehicle usability. The key components of dynamic WPT systems are the coils and their compensation topologies. This paper provides a detailed analysis of these elements to optimize system performance. First, different coil geometries are systematically evaluated using finite element analysis, aiming to identify designs that minimize electrical parameter variations, which can damage electronics and make the control more complex. Then, the most suitable compensation topology is determined through time-domain analysis, which is more accurate under dynamic conditions than the commonly used phasor-based approach. This design process based on time-domain analysis is validated with a 100 W dynamic charger prototype, demonstrating the system's transient behaviour. Experimental results show an efficiency of up to 80% and high tolerance to misalignment under various load conditions.