STUDY ON SELF-ENCODING CONTROL ROD POSITION DETECTOR

This paper describes a new kind of control rod position detector for n uclear reactors - the self-encoding control-rod position detector It c onsists of several induction coils arranged along the longitudinal axi s of the rod and its core. The core is made up of magnetic and non-mag netic rods arranged alternately When the rod is withdrawn, the core en codes, but the coils do not. By processing the output of the coils, th e binary codes related to rod position are derived. Compared with the coil-encoding detector used in pressurized water reflectors (PWRs), th e self-encoding position detector is simpler in structure, and more re liable in operation. It is suitable for indicating the position of hyd raulic-drive control rods in Nuclear Heating Reactors (NHR), and also for magnetic-drive control rods in PWRs.