James A. Neuner

A Microprocessor Based Automatic Flux Mapping System for Pressurized Water Reactors

A microprocessor controlled Flux Mapping System has been designed which permits automatic three-dimensional flux distribution measurements of a reactor core. The Flux Mapping System consists of a Detector Drive System which provides the mechanical means for routing movable detectors into and out of the core, and a Flux Mapping Console which allows for complete and automatic control of drive system operation, data gathering and system output. Both the Flux Mapping Console and the detector Drive System, their features and construction, are described. The console design is implemented using multiple microprocessors with a redundant internal architecture and a modular bus oriented construction that uses standard printed circuit boards. Overator interface is via an interactive CRT and keyboard. Low level analog signals from the detectors are digitized; scanning is synchronized with detector position; and automatic ranging is utilized for maximum resolution. Multiple data links allow data to flow from memory to printers, floppy discs, and a plant process computer. The microprocessors perform self-checking and system diagnostics for maximum system availability.

Microprocessor-Based Architecture for a Modular Process Protection Upgrade System

The Westinghouse Process Protection Upgrade System (Eagle 21TM) is a functional replacement for the existing analog process protection equipment used to monitor nuclear generating stations and actuate the reactor trip and engineering safeguards systems as required. However, the Eagle 21TM system does more than merely replace the existing analog hardware; it exploits the power of a functionally decentralized architecture with multiple independent microprocessorbased subsystems to increase plant availablity, reduce test time, reduce reconfiguration time, and increase the amount of information available to the operator and to new diagnostic systems. The architecture of the system is described and the major benefits are highlighted.

An Advanced Digital ROD Postion Indication System for Pressurized Water Reactors

A new digital Rod Position Indication (RPI) System is described. It is a replacement for analog RPI systems in pressurized water reactors. The new RPI system provides substantial improvements in plant availability, system maintenance, fault tolerance and control room man-machine interface. A new sensing technique reduces systems complexity and eliminates time consuming costly adjustments. A fault tolerant, redundant microprocessor based system architecture and extensive embedded diagnostics ensure plant availability and reduce the need for system maintenance. Reduced electrical interconnection requirements frees many containment penetrations for alternative uses. All external interfaces are designed for low installed cost. Display of rod position, alarms, and diagnostic information are provided in analog and digital formats on a compact color CRT in the control room.

A Fault Tolerant Multiplexed Control Rod Position Detection and Indication System for Nuclear Power Plants

The majority of Westinghouse nuclear plants placed in service thus far have incorporated a Rod Position Indication system based upon an analog design philosophy. This system, while meeting all functional and accuracy requirements, has proven somewhat cumbersome, particularly in the area of initial field calibration and maintenance. This paper describes a new Digital Rod Position Indication system (DRPI) developed for use with pressurized water reactors. The system is based upon a digital design philosophy and meets all previous design constraints and environmental requirements, Further, fault tolerance, improved accuracy, interference from adjacent rods and the elimination of adjustments and calibration has been provided.

A Computerized Axial Power Distribution Monitoring System for Pressurized Water Reactors

Minicomputer implementation has proven successful in developing the Axial Power Distribution Monitoring System (APDMS) which is used to monitor the axial power shape within some pressurized water reactors. The APDMS and its main subsystems are described. A control subsystem interfaces the APDMS to existing plant equipment. A dedicated minicomputer is introduced into the system to enhance its capabilities. The features of the minicomputer subsystem are described. The computer is also capable of performing continuous on-line testing and self-checking. Techniques for improving system availability and security are presented. Current operating experience has demonstrated that the APDMS serves a useful function in plant operation. In addition, the computer subsystem has demonstrated its reliability and practicality in the plant environment.