Current Limiting Properties of MOD-YBCO Thin Films Stabilized With High-Resistivity Alloy Shunt Layer

Switching power densities of current limiting elements consisting of metal organic deposition YBa₂Cu₃O₇ (MOD-YBCO) thin films with high-resistivity Au-Ag alloy shunt layers and non-inductive Manganin resistors are evaluated. Despite the non-uniform critical current density distribution in MOD-YBCO films, the use of a high-resistivity Au-Ag shunt layer allows MOD-YBCO-based elements to achieve switching power densities comparable to those obtained for elements based on co-evaporated YBCO thin films. The present MOD-YBCO-based elements are capable of withstanding electric fields of 46 V/cm with a switching power density of 2.0 kVA/cm². These results indicate that low cost MOD-YBCO thin films are promising for practical fault current limiters. In addition, relationships between the uniformity of J_c distribution and current limiting properties are also discussed.