3-D Wireless Power Transfer With Orthogonal Transmitters and Adaptive MPC-MPPT

This paper presents a three-dimensional wireless power transfer (3D-WPT) system that uses three transmitting coils oriented in orthogonal directions and an adaptive model predictive control (MPC) strategy that incorporates maximum power point tracking (MPPT). The framework combines MPC's predictive optimization and MPPT's efficiency-seeking behavior, which simultaneously optimizes power tracking accuracy, system efficiency, and current distribution, while maintaining zero-voltage-switching (ZVS) operation. The dynamic weight-adjustment mechanism alters the weights of competing objectives automatically and based on the current operational conditions. The system model indicates that power distribution in 3D space fits a Lemniscate of Bernoulli surface revolved about its longitudinal axis, so the rotational Lemniscate of Bernoulli surface is important to the control design. The experimental results presented in this paper show up to 20% increased efficiency at 40 cm transmission distance, and a peak efficiency of 87% at 60W and at 40<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\times 40\times$</tex-math></inline-formula>40cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> charging volume. The framework provides stable power delivery while the receiver is in motion, making it appealing for applications that require spatial freedom, including mobile robots and bio-inspired aerial vehicles.