Plant monitoring and diagnosing method and system, as well as plant equipped with the system

• US 5,623,109 A
• Filed: 05/20/1994
• Issued: 04/22/1997
• Est. Priority Date: 05/21/1993
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Uchida, Shunsuke, Yamada, Izumi, Takahashi, Fuminobu, Fujimori, Haruo, Fukuzaki, Takaharu
• Primary Examiner(s): RAEVIS, ROBERT R
• Application Number:
  US08/247,039
• Time in Patent Office: 1,068 Days
• Field of Search: 73/799, 73/865.8, 73/866, 73/865.9, 376/215, 376/216, 376/245, 364/507
• US Class Current: 73/865.9
• CPC Class Codes: G05B 23/0254 based on a quantitative model, e.g. mathematical relationships between inputs and outputs; functions: observer, Kalman filter, residual calculation, Neural Networks
• CPC Class Codes: G05B 23/0259 characterized by the response to fault detection
• CPC Class Codes: G21C 17/00 Monitoring; Testing measuring in general G01; Maintaining
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

Plant operating conditions 1, apparatus operating conditions 2 and environment conditions 3 are accumulated, combined and put together as a set of plant status variables 8 -through a monitor 6, while water chemistry information 4 is accumulated as another set of plant status variables 9. The set of status variables 8 is updated and the past data are accumulated in the set of status variables 9. Periodical inspection data 5 are also accumulated in the set of status variables 9 along with the water chemistry information 4. The set 9 is compressed and stored as a plant chart 11 such as a personal clinical chart. A status variable prediction 12 is performed in consideration of the personality of a plant. Both data of the sets 8 and 10 are compared with each other by comparison means 13. If both the data nearly coincide with each other, the plant is diagnosed to be normal and, if not, it is diagnosed to be abnormal. When the plant is diagnosed to be abnormal, an abnormal apparatus and an abnormal factor are identified.

Claims

1. A method of monitoring and diagnosing plant conditions comprising the steps of:

detecting and accumulating plant operating conditions, apparatus operating conditions and environment conditions;

inputting and accumulating plant inspection data; and

monitoring and diagnosing said plant conditions based on plant record information including said accumulated detection data and inspection data;

wherein said inputting and accumulating plant inspection data comprises;

inputting a first set of detection data of a first type relating to a given characteristic of a plant element to be diagnosed, and

inputting a second set of detection data of a second type relating to said given characteristic but different from said first type of detection data; and

wherein said diagnosing comprises;

determining a correlation between said first set of detection data;

calibrating said determined correlation using said second set of detection data; and

storing said calibrated correlation as a plant chart for monitoring and diagnosis; and

comparing said calibrated correlation stored as a plant chart and a correlation of a third set of detection data, said third set of detection data being of said first type.

3. A method of monitoring and diagnosing plant conditions according to claims 1 or 2, wherein said first step further includes a step of inputting inspection data from a plant;

and taking said inspection data into consideration to determine said correlation as a plant chart for monitoring and diagnosis.

4. A method of monitoring and diagnosing plant conditions according to claims 1 or 2, wherein when an abnormality is detected in said first step, an abnormal location and abnormal details are identified and an event which will ensue from the abnormality is predicted.

5. A method of monitoring and diagnosing plant conditions according to claim 4, wherein said identified abnormal location and details and said event which will ensue from the abnormality are indicated by display means.

6. A method of monitoring and diagnosing plant conditions according to claim 4, wherein a countermeasure for dealing with the detected abnormality is selected, and said identified abnormal location and details, said event which will ensue from the abnormality, and a countermeasure are indicated by display means.

7. A method of monitoring and diagnosing plant conditions according to claims 1 or 2, wherein a residual life for said plant element is evaluated based on the data in the plant chart and material degradation data calculated from the plant chart data.

8. A method of monitoring and diagnosing plant conditions according to claim 7, wherein an effect of crack propagation is evaluated based on the data in the plant chart, the inspection data, and the material degradation data, in terms of crack incubation time until microscopic cracks coalesce to become a macroscopic crack, a propagation length of the macroscopic crack, and a critical crack length which reflects deterioration of the material strength, thereby evaluating a residual life for said plant element.

2. A method of monitoring and diagnosing plant conditions comprising the steps of:

detecting and accumulating plant operating conditions, apparatus operating conditions and environment conditions;

inputting and accumulating plant inspection data; and

monitoring and diagnosing said plant conditions based on plant record information including said accumulated detection data and inspection data;

wherein said plant record information is stored in the form of a plant chart in which said detection data and said inspection data are compressed and accumulated, and the plant conditions are diagnosed based on the data in said plant chart; and

wherein said detection data and said inspection data each comprise plural kinds of data, these plural kinds of data are given with predetermined weights before the plant conditions are monitored and diagnosed, these predetermined weights are changed in accordance with the result of diagnosing the plant conditions, and these changed detection data and said inspection data are compressed and stored as the data in said plant chart;

and wherein one of said plural kinds of detection data relates to a given operating condition;

and further comprising;

determining a first plurality of values of said given operating condition for the respective different detection data using said inputted plurality of detection data; and

storing correlations of said first plurality of values of said given operating condition as said plant chart for monitoring and diagnosis; and

wherein said diagnosing comprises comparing said correlation of said first plurality of values of said given operating condition stored as said plant chart and correlations of a second plurality of values of said given operating condition for the respective different detection data determined using a second plurality of values of said plurality of different detection data to monitor and diagnose an abnormality in a plant element relating to said operating condition.