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

• US 5,817,958 A
• Filed: 08/05/1996
• Issued: 10/06/1998
• Est. Priority Date: 05/20/1994
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Fujimori, Haruo, Uchida, Shunsuke, Yamada, Izumi, Takahashi, Fuminobu, Fukuzaki, Takaharu
• Primary Examiner(s): RAEVIS, ROBERT R
• Application Number:
  US08/691,007
• Time in Patent Office: 792 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: G21C 7/36 Control circuits
• CPC Class Codes: G21D 3/04 Safety arrangements emergency protection of reactor G21C9/00
• CPC Class Codes: Y02E 30/00 Energy generation of nuclear origin
• 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 the normal and, if not, it is diagnosed to be abnormal. When the plant is diagnosed to abnormal, an abnormal apparatus and an abnormal factor are identified.

Claims

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

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

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;

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

a second step of 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, to monitor and diagnose an abnormality in the plant element.

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

3. A method of monitoring and diagnosing plant conditions according to claim 2, wherein said identified abnormal location and details and said event which will ensue from the abnormality are indicated by display means.

4. A method of monitoring and diagnosing plant conditions according to claim 2, 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.

6. A method of monitoring and diagnosing plant conditions according to claim 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.

5. A method of monitoring and diagnosing plant conditions comprising:

a first step of inputting a plurality of different detection data relating a given plant operating condition;

determining a first plurality of values defining said plurality of different detection data; and

storing a first correlation of said first plurality of values as a plant chart for monitoring and diagnosis; and

a second step of comparing said first correlation of said first plurality of values stored as a plant chart and a correlation of a second plurality of values, said second plurality of values being current values defining said plurality of different detection data to monitor and diagnose an abnormality in a plant element relating to said plant operating condition;

wherein when an abnormality is diagnosed in the second step, a location of the abnormality and a plurality of details regarding an event which will ensue from the abnormality are predicted and indicated on a display means, and wherein a countermeasure for responding to the details regarding the ensuing event is also predicted and indicated on a display means.

7. A method of monitoring and diagnosing plant conditions according to claim 5, 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 said first step further comprises inputting inspection data from a plant;

and

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 a 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.