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INVESTIGATION OF REACTOR CONDITION MONITORING AND SINGULARITY DETECTION VIA WAVELET TRANSFORM AND DE-NOISING

  • Kim, Ok-Joo (Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology) ;
  • Cho, Nan-Zin (Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology) ;
  • Park, Chang-Je (Korea Atomic Energy Research Institute) ;
  • Park, Moon-Ghu (Korea Electric Power Research Institute)
  • Published : 2007.06.30

Abstract

Wavelet theory was applied to detect a singularity in a reactor power signal. Compared to Fourier transform, wavelet transform has localization properties in space and frequency. Therefore, using wavelet transform after de-noising, singular points can easily be found. To test this theory, reactor power signals were generated using the HANARO(a Korean multi-purpose research reactor) dynamics model consisting of 39 nonlinear differential equations contaminated with Gaussian noise. Wavelet transform decomposition and de-noising procedures were applied to these signals. It was possible to detect singular events such as a sudden reactivity change and abrupt intrinsic property changes. Thus, this method could be profitably utilized in a real-time system for automatic event recognition(e.g., reactor condition monitoring).

Keywords

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