THERMAL AND ELECTRICAL STABILIZATION OF HIGH-TEMPERATURE SUPERCONDUCTOR POWDER-IN-TUBE CONDUCTOR

High-temperature superconductor (HTS) powder-in-tube conductors often require thermal and/or electrical stabilization to ensure their long-t erm integrity. An example of such a stabilization need is the safety b ypass lead of an HTS current lead intended for application to supercon ducting magnetic energy storage (SMES) devices. The bypass lead functi ons include current sharing during upset conditions and conductor elem ent temperature control. This paper presents a bypass lead design for an HTS current lead in an 0.5 MW h SMES system. Included are predictio ns of thermal and electrical stabilization and current lead heat leaks . The results of a supporting development program are presented as are details of a method to connect conductor element/bypass leads, an ass embly procedure, a cleaning method, and thermal-stress tolerance measu rements.