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Abstract Research on magnetically resonant wireless power transfer (MRWPT) is actively pursued for diverse applications. Dependent on magnetic fields for wireless power transfer (WPT), MRWPT encounters a challenge due to the absence of monopole magnetic properties, impacting power transfer efficiency (PTE) sensitivity to receiver arrangement. Despite extensive research, achieving the desired receiver freedom remains a persistent challenge—a core limitation rooted in magnetic field‐based WPT. To address this, electrically resonant wireless power transfer (ERWPT) is proposed, utilizing an open bifilar coil at a resonant frequency. Experimental results demonstrate nonradiative power transfer of up to 50 watts and 46% PTE over a distance of 2 meters, maintaining consistent PTE performance. This phenomenon arises from the electric charge's monopole capability, distinguishing it from the limitations associated with magnetic fields. The practical viability of this system is delved and suggest directions for further investigation. ERWPT overcomes MRWPT challenges, ensuring lateral plane consistent efficiency and offering a breakthrough for practical wireless power applications.

The eddy current loss caused by the conductivity of seawater results in a relatively low transfer efficiency of underwater wireless power transfer (WPT). And the transfer distance of the current WPT system is relatively short. Considering that most of the wireless power transfer devices in practical applications are asymmetric, few studies have explored the transfer characteristics of asymmetric midrange WPT in seawater. In this study, it is experimentally found that the load voltage and transfer efficiency of an asymmetric midrange WPT system with reduced primary balancing resistance in seawater are nearly twice as high as those of a symmetric one at a 50 cm transfer distance and a 410 kHz operation frequency with a 44.4 Ω load resistance. A new circuit model of the underwater WPT system with complex impedance and complex mutual inductance is then presented, and the load voltages predicted by the model are consistent highly with the experimental values; the model is then utilized for the explanation of the experimental observations. Changing the load resistance also improves the transfer efficiency of the system; however, the eddy current loss results in a relatively low transfer efficiency of 30.9% at an optimal load resistance of 90 Ω. The asymmetric midrange underwater WPT system can be applied in scenarios where the transfer distance is prioritized.

ABSTRACT In order to search for an ideal test for multiple comparison procedures, this study aimed to develop two tests, similar to the Tukey and SNK tests, based on the distribution of the externally studentized amplitude. The test names are Tukey Midrange (TM) and SNK Midrange (SNKM). The tests were evaluated based on the experimentwise error rate and power, using Monte Carlo simulation. The results showed that the TM test could be an alternative to the Tukey test, since it presented superior performances in some simulated scenarios. On the other hand, the SNKM test performed less than the SNK test.