Current limitation at 1080 A under 1100 V with bulk Bi-2223

The superconducting current limiter could bring a solution to a problem not satisfactory solved : the limitation of fault currents under high voltages . We carry out a research and development program based on bulk Bismuth mat erials. They are attractive due to their homogeneous quench into the resist ive state and after the normal state even if their critical current densiti es are not very high (several MAm-2 at 77 K, self field). They limit effici ently currents without any risk of burning (no hot spots) even under high e lectrical fields. These materials are elaborated in the form of Bi-2223 bar s formed by an isostatic pressure and classical sintering. Sixty bars (O = 4 mm, l = 120 mm, I-c = 35 A) were assembled. This assembling was tested up to 1100 V at 1080 A instead of a theoretical value of 5000 A. The supercon ductor was exposed to a maximum power density of 12 GW/m(3) without damage. We present the measurements obtained on the bars and their assembling.