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Thermal effects on a high frequency resistance of a high-ampacity conductor based on Carbon Nanotube Fibers (CNTF) yarn is presented in this paper. AC resistances of the CNTF yarn conductors are modelled as function of frequency and temperature considering the manufacturer specifications of the CNTF yarn conductors. Also, the model is applied on copper (Cu), and then both of the results from Cu and CNTF yarn conductors were compared. The thermal effects on both conductors are verified at high frequency operation using experimental results. Firstly, the DC resistance is measured to verify the temperature coefficient for both Cu and CNTF yarn conductors. Then, the AC is also measured to compare. The results show that the calculated AC resistance values at different temperatures and frequencies match the measured values for both CNTF yarn and Cu conductors. Rate of the resistance increase in CNTF yarn with the temperature is lower than that of Cu, because CNTF yarn has the lower temperature coefficient (${\alpha }$). The AC resistances for both CNTF yarn and Cu decrease with increasing the temperature due to the increase in the skin depth (${\delta }$). The hardware test verifies that CNTF yarn’s skin depth is significantly larger than Cu, and the increasing rate of the AC resistance with temperature in CNTF yarn is lower than Cu. Therefore, employing CNTF yarn as high-ampacity conductors is advantageous due to the high thermal stability compared to Cu conductors. [ABSTRACT FROM AUTHOR]

Although a large number of typical resonant converter topologies have been developed for use in contactless power transfer applications, these topologies need to be precisely optimized to obtain maximum efficiency and maximum power transferring capacity. High-order resonant power converters with flexible designs are invariably required to develop energy-efficient and cost-effective converter systems. An ideal converter topology can contribute toward realizing efficient converter systems if it is capable of providing an optimized output that is insensitive to load variations, coupling coefficient, type of the wireless transformer used, and other operating conditions. This paper presents a new contactless power converter topology for a low-coupling (0.14) ferrite-core transformer that has low cost, small size, high efficiency, and a wide gap (20 mm). In addition, the merits and demerits of conventional converter topologies are studied herein, and results for these topologies are compared with those for the proposed converter topology. [ABSTRACT FROM PUBLISHER]