Abstract
BWR-instabilities can occur in fundamental mode with in-phase core wide oscillations or in excited modes as out-of-phase oscillations. The fundamental mode can be successfully monitored with DR (Decay Ratio) and amplitude calculations while the out-of-phase oscillations demands phase analysis between the LPRM-signals in different parts of the core. The present report describes how the BWR-stability monitor FASMON detects such excited modes and presents the topology of the flux swing in a horizontal plane in the core. FASMON is the only available method to detect out-of-phase oscillations fast (within 20 seconds) and robust. The FASMON algorithm is based on adaptive recursive filtering technique. All investigations with FASMON presented in this report show that the software is a good monitor tool. The software makes surveillance of the phase differences and amplitudes for a number of LPRM signals. The method to calculate the phase differences is robust with the following characteristics: The response time within 20 seconds for the FASMON algorithm is very short; Robust - works even under transient conditions; Independent of the signal amplitude; A dead sensor in a LPRM-pair does not cause alarm. The report gives results from investigations using FASMON both on theoretical and measured signals. As a conclusion
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Citation Formats
Bergdahl, B G, and Oguma, R.
FASMON monitoring of space dependent oscillations in a BWR.
Sweden: N. p.,
1994.
Web.
Bergdahl, B G, & Oguma, R.
FASMON monitoring of space dependent oscillations in a BWR.
Sweden.
Bergdahl, B G, and Oguma, R.
1994.
"FASMON monitoring of space dependent oscillations in a BWR."
Sweden.
@misc{etde_10111836,
title = {FASMON monitoring of space dependent oscillations in a BWR}
author = {Bergdahl, B G, and Oguma, R}
abstractNote = {BWR-instabilities can occur in fundamental mode with in-phase core wide oscillations or in excited modes as out-of-phase oscillations. The fundamental mode can be successfully monitored with DR (Decay Ratio) and amplitude calculations while the out-of-phase oscillations demands phase analysis between the LPRM-signals in different parts of the core. The present report describes how the BWR-stability monitor FASMON detects such excited modes and presents the topology of the flux swing in a horizontal plane in the core. FASMON is the only available method to detect out-of-phase oscillations fast (within 20 seconds) and robust. The FASMON algorithm is based on adaptive recursive filtering technique. All investigations with FASMON presented in this report show that the software is a good monitor tool. The software makes surveillance of the phase differences and amplitudes for a number of LPRM signals. The method to calculate the phase differences is robust with the following characteristics: The response time within 20 seconds for the FASMON algorithm is very short; Robust - works even under transient conditions; Independent of the signal amplitude; A dead sensor in a LPRM-pair does not cause alarm. The report gives results from investigations using FASMON both on theoretical and measured signals. As a conclusion the investigation of the instability shows that FASMON works even under circumstances with in-phase conditions and low amplitude up to unstable conditions with out-of-phase oscillations and high amplitude. 5 refs, 12 figs.}
place = {Sweden}
year = {1994}
month = {Aug}
}
title = {FASMON monitoring of space dependent oscillations in a BWR}
author = {Bergdahl, B G, and Oguma, R}
abstractNote = {BWR-instabilities can occur in fundamental mode with in-phase core wide oscillations or in excited modes as out-of-phase oscillations. The fundamental mode can be successfully monitored with DR (Decay Ratio) and amplitude calculations while the out-of-phase oscillations demands phase analysis between the LPRM-signals in different parts of the core. The present report describes how the BWR-stability monitor FASMON detects such excited modes and presents the topology of the flux swing in a horizontal plane in the core. FASMON is the only available method to detect out-of-phase oscillations fast (within 20 seconds) and robust. The FASMON algorithm is based on adaptive recursive filtering technique. All investigations with FASMON presented in this report show that the software is a good monitor tool. The software makes surveillance of the phase differences and amplitudes for a number of LPRM signals. The method to calculate the phase differences is robust with the following characteristics: The response time within 20 seconds for the FASMON algorithm is very short; Robust - works even under transient conditions; Independent of the signal amplitude; A dead sensor in a LPRM-pair does not cause alarm. The report gives results from investigations using FASMON both on theoretical and measured signals. As a conclusion the investigation of the instability shows that FASMON works even under circumstances with in-phase conditions and low amplitude up to unstable conditions with out-of-phase oscillations and high amplitude. 5 refs, 12 figs.}
place = {Sweden}
year = {1994}
month = {Aug}
}