Inductance Control Rod osition Detector for Nuclear Heating Reactor

摘要

The ultrasonic wave control rod position detector used in the 5MW Nuclear Heating Test Reactor and the coils coding CRPD used extensively in water reactors have some defects. Three new kins of CRPDs are described in this paper. The first is the GRAY code rod position detector; it ocnsists of 5 grouped secondary coils and one coding bar. As the control rod is withdrawn, the coding bar passes the coils and changes their output signals. By pickign up and processing the signals, 5 bits binary GRAy code which is related to the rod position is obtained. The second is the self-encoding rod position detector; it ocnsists of 8 secondary coils nad a coding bar. As the CR moves, 8 output signals indicating the rod position will be changed. The third is the digital-analog rod position detector; it consists of two long opposite and two short secondary coils arranged on the longitudinal axis of the rod housing nad a coding bar. WHile the bar passes the coils, their outputs which indicate the rod positio will be changed, The comparision of the four kinds of CRPDs illustrates that the new kinds are simpler in structure, more reliable in operation and lower manufacture cost. The manufacture process of all the new kinds of detectors are the same as that of the coils coding CRPD, and the latter is a ripe technology. So they can be sued in NHRs and other water reactos.