Study on Rod Position Indication System using Permanent Magnets with Shielding Plates for a Control Rod Drive Mechanism

  • Received : 2015.09.25
  • Accepted : 2015.12.02
  • Published : 2015.12.31


A control rod drive mechanism (CRDM) is an electromechanical equipment that provides linear movement for the control rods to control the nuclear reactivity in a nuclear reactor. A rod position indication system (RPIS) detects the control rod's position. To enhance the measurement accuracy of the system, a magnetostrictive type sensor with capability of generating operation limiting signals would be adapted instead of a conventional RPIS for a CRDM. An RPIS was modelled for a numerical analysis with the permanent magnets at the stationary limit positions and magnetic shielding plates with a moving permanent magnet. The performance analysis of the RPIS were conducted, and the results were discussed here.



Supported by : National Research Foundation of Korea (NRF)


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