The electro-thermal behavior of the HTS materials, is a critical aspect for design efficient and low-cost power applications based on high-temperature superconductor. In order to optimize cost and performance, one needs to know the behavior of the parts of the tapes: the electro-thermal properties of the materials used in the manufacturing of those tapes (e.g. alloy substrate, silver and copper) are well known. On the contrary, certain properties of the superconductors are much more challenging. The electrical resistivity strongly depends on the current density flowing through it (J), on the temperature (T) and on the magnetic field (B). Extracting the superconductors intrinsic resistivity (J,B,T) functional dependence from voltage-current (V-I) characteristics measured on a tape is very difficult, because of the electrical and thermal interplay between the various layers. The major challenge lies in the fact that as soon as the transport current (I) in a HTS conductor becomes higher than its macroscopic critical current (Ic), heating effects and thermal instabilities occur and quickly destroy the conductor if nothing is done to protect it. The way to overcome this problem and characterize the over-critical current regime is to use a pulsed current measurement technique (PCM) which, acting on the time scale of microseconds, allows precise isothermal resistivity measurements in the flux-flow regime - the most important one for power applications operating near and above Ic. Due to a wide range of complexities as the material properties, temperature gradients and cooling conditions, numerical models are essential tools for extracting the superconductors behavior from the measured characteristic. This work will present results of PCM measurements, e.g. flux-flow resistivity at constant temperatures, which are of paramount importance for the development of efficient superconducting devices.
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