Valid Signal Isolation Method for Loose Parts Monitoring System in the Main Circulation Circuit of WWER Reactor

Loose, poorly fastened and foreign parts are likely to appear in the main circulation circuit of WWER reactors. These parts carried by the coolant flow can collide with the inner walls of the main circulation circuit components transferring energy to the reactor hardware. The shock causes acoustic anomaly in the materials the equipment and pipelines are made of (a burst of acoustic noise). In order to detect such phenomena, WWER reactors are equipped with loose, poorly fastened and foreign parts monitoring systems (LPMS) based on recording acoustic signals on the surface of reactor equipment. The availability of significant background noise in certain power unit operating modes results in the valid shock signal being fully masked. The paper focuses on valid signal isolation method based on spectral whitening and provides examples of applying it to the data recorded by LPMS of WWER reactor

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