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Title: Reactor protection system with automatic self-testing and diagnostic

A reactor protection system having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically "identical" values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through outputmore » relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic.« less
Authors:
 [1]
  1. (Cupertino, CA)
Publication Date:
OSTI Identifier:
870746
Report Number(s):
US 5586156
DOE Contract Number:
AC03-89SF17445
Resource Type:
Patent
Research Org:
General Electric Co
Country of Publication:
United States
Language:
English
Subject:
reactor; protection; automatic; self-testing; diagnostic; reactor; protection; divisions; quad; redundant; sensors; scram; parameter; providing; input; independent; microprocessor-based; electronic; chassis; electronic; chassis; acquires; scram; parameter; data; sensor; digitizes; information; transmits; sensor; reading; electronic; chassis; via; optical; fibers; increase; availability; reduce; false; scrams; reactor; protection; employs; levels; voting; reactor; scram; electronic; chassis; perform; software; divisional; data; processing; vote; spare; based; information; sensors; send; divisional; scram; signals; hardware; logic; panel; performs; division; vote; initiate; reactor; scram; chassis; makes; divisional; scram; decision; based; data; sensors; automatic; detection; discrimination; failed; sensors; allows; reactor; protection; automatically; enter; sensor; failures; occur; communication; sensor; readings; allows; comparison; theoretically; identical; values; permits; identification; sensor; errors; drift; malfunction; diagnostic; request; service; issued; errant; sensor; data; automated; diagnostic; monitoring; sensor; input; output; relay; logic; virtually; eliminate; manual; surveillance; testing; provides; ability; division; cross-check; divisions; sense; failures; hardware; logic; reactor scram; reactor scram; reactor protection; reactor protection; reactor protection; reactor protection; parameter data; scram signal; data processing; optical fibers; optical fiber; electronic chassis; electronic chassis; electronic chassis; electronic chassis; reduce false; sensor input; microprocessor-based electronic; scram parameter; scram parameter; providing input; quad redundant; redundant sensors; chassis acquires; parameter providing; virtually eliminate; independent microprocessor-based; via optic; automatic detection /376/700/702/