Current limiter for AC system - has at least two saturable chokes for each phase

摘要

At least two chokes are provided for each phase of the a.c. system whose current is to be limited. Each choke has an a.c. winding and a superconducting d.c. biasing winding keeping the core saturated under full a.c. load conditions. An air-gap core is linked with the biasing winding. A.c. windings in each phase are so arranged and connected, that under full load conditions a change of saturation level is any choke core w.r.t. the biasing level, due to the biasing winding alone, is accompanied by a compensating saturation level change in another core(s). Current limiting takes place when in each half-period one or the other core is driven from saturation.