Abstract: The present invention is a component monitoring system which includes all sensor and plant component monitoring at distributed plant locations close to the sensors which are the source of the signals to be analyzed. Minimally preconditioned analog sensor signals are multiplexed and further conditioned by a sensor signal preprocessor that adjusts the gain and filters the sensor signals before being applied to an analog-to-digital converter controlled by a data acquisition computer. The analog sensor signals are converted into digital samples and stored in a data memory of a digital signal processor using a direct memory access technique. The data acquisition computer also controls the selection of sensors, gain, etc., based on commands from a controller. The digital signal processor, once sufficient sensor data has been collected, performs appropriate processing using known digital signal processing techniques.

Abstract: A nuclear reactor monitoring system includes incore and excore neutron detectors for producing neutron noise signals and system data including at least one of reactor coolant pump motor current, temperature and pressure of the reactor coolant system and pressurizer pressure and means for diagnosing conditions of the reactor internals and core support structures by comparing analyzed instrumentation signatures. The signatures may be derived from scale model test data, plant test data, analytical model results and trending analysis results. Analyses performed by the system include time and frequency domain analyses of the neutron noise signals and the system data. The analyzed data are compared with rules in a rules base of an expert system to generate a diagnosis of the condition of the reactor internals and core support structures and action recomendations for maintenance of the nuclear reactor.

Abstract: The impact signal derived from an acoustic transducer has a unique signature represented by its frequency spectrum. The present invention generates under predetermined conditions with objects, each of definite weight and form, a series of impact signals for reference purposes and correlates an actual impact signal from an unknown impacting object with such reference impact signals by comparing the frequency spectra, thereby to indirectly recognize the impacting object.