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SUMMARY Shielding principles are essential for guiding the efficient design of effective shields. In this paper, equivalent magnetic dipoles are first introduced to discuss shielding mechanism and characteristics of finite‐width metal plates. It is found that the magnetic field contributed by a plate decays with 1/r2 or 1/r3 generally. Magnetic shielding is effective if both equivalent and source dipoles have the same orientation. Such shielding retains even at infinity. Shielding is ineffective if their orientations are different. In such a case, an edge effect is observed no matter what material the plate is made of. The edge effect of conducting plates can be eliminated if two connected plates are placed around the source. Shielding against a monopole source is observed in the near region, even with a conductive plate. Monopole‐source shielding with a ferromagnetic plate is almost the same as dipole‐source shielding under orthogonal dipole orientations. Impact of other parameters, such as plate location, size and material, is addressed and interpreted physically using the equivalent dipoles. Copyright © 2013 John Wiley & Sons, Ltd.

Shielding effectiveness (SE) and coupling characteristic of metallic enclosures with apertures excited by EMP are investigated. The coupling results of different configurations and number of apertures are discussed. The coupled electric field strength is the highest in the small area adjacent to the aperture. The electric field evolvement exhibit resonant behaviour evidently and the resonant peak is present at the center inside the enclosure. For the case of the same area of a single aperture, the SE of the enclosure with rectangular aperture is lowest, and which with circle aperture is highest. The SE of the enclosure with double-layers wall is improved significantly. Besides, keeping the total area unaltered, dividing the single larger aperture into multiple smaller apertures, the SE of the enclosure will be increased.

Misalignments between the transmitter and receiver coils would in some cases lead to a significant decline in transmission power and efficiency in the wireless power transfer system. This study presents an integrated two‐layer receiver to improve the tolerance of horizontal misalignment. On the lower layer of the integrated receiver, two coplanar spiral coils, which are decoupled and work as the auxiliary repeater, are designed to help keep a stable power transmission between transmitter coils on the track and the main receiver coil on the upper layer. Then, the optimisation model based on the Bayesian algorithm is established for the proposed receiver structure and some key parameters are optimised. A sensor‐coil‐based positioning approach is also proposed to achieve on–off control of the transmitter coils. The simulation results show that the system based on the optimised integrated receiver has a stable output power with a variation lower than 13.17%. Two 300 W dynamic charging prototypes based on the integrated receiver and conventional spiral receiver, respectively, have been developed to verify the effectiveness of the proposed design and the optimisation method. The experimental results match well with the simulation results.