PLANT DIAGNOSTIC DEVICE AND PLANT DIAGNOSTIC METHOD

摘要

Provided is a plant diagnostic device able to detect forewarning that the plant is on the way form normal to abnormal status. The plant diagnostic device diagnoses the plant's operational status on the basis of a measurement signal in which a state quantity is measured from the plant, and displays the diagnostic result on an image display device. The plant diagnostic device is provided with: a learning means for constructing a model used in the diagnosis using the measurement signal that measures the state quantity of the plant; and a diagnostic means for diagnosing the operational status of the plant using the model built by the learning means. The learning means has a categorization unit that categorizes data with similar values into the same category; a period determination unit that determines the normal period, forewarning period and abnormal period by assessing the difference in trends in the measurement signal on the basis of the categorization result of the categorization unit; and a model construction unit that constructs a normal model using measurement signals in the normal period. The plant diagnostic device is configured so that the diagnostic means determines whether or not the measurement signal at the current time is categorized into the normal model constructed by the model construction unit; and in the case that the measurement signal at the current time is within the normal model, diagnoses that the plant is in normal status and such is displayed on the image display device; and in the case that the measurement signal at the current time is not within the normal model, diagnoses that the plant is in an unknown status not experienced previously and such is displayed on the image display device.