Quench propagation in YBCO pancake: experimental and computational results

High-temperature superconductors are promising materials for future applications such as high field magnets thanks to their ability to carry high current densities. Nevertheless, their protection still remains a key issue mainly due to the slow velocity of quench propagation. To understand the quench behavior of a YBCO coil, a simulation code has been developed using the CASTEM-CEA finite element software. Simulations can be performed considering constant current and magnetic field. Results of those simulations will be displayed and a way for improving the protection by adding a stabilizer will be discussed. Two well instrumented YBCO coils were fabricated in order to obtain experimental data on quench propagation in pancake configuration. Their design and some measurements are reported in this paper along with another experiment on a double pancake made by and tested at CNRS Grenoble. Finally, we compare the numerical and experimental results and discuss the accuracy of our simulations.