WM. H. Zimmer nuclear power station information management system

Progress in Nuclear Energy, Vol. 12, No. 3, pp. 209 212, 1983. 0149 1970/83 $0.00+.50 Printed in Great Britain. All fights reserved. Copyright I i 1983 Pergamon Press Ltd. WM. H. ZIMMER NUCLEAR POWER STATION INFORMATION MANAGEMENT SYSTEM D. RILEY*, R. KANITZ~ and E. BURKHALTER~ * Cincinnati Gas & Electric Company, Wm. H. Zimmer Nuclear Power Station, Box 2023, Moscow, Ohio 45153, U.S.A. 1" General Physics Corporation, 10650 Hickory Ridge Road, Columbia, Maryland 21044, U.S.A. ~: Burk Associates, 5164 Scarecrow Court, Columbia, Maryland 21045, U.S.A. (Received 22 August 1983) 1. INTRODUCTION This article presents a chronological essay concerning the planning, development and implementation of several computer systems at the Wm. H. Zimmer Nuclear Power Station. The Wm. H. Zimmer Nuclear Power Station is a BWR 5 rated at 2436 MWt located on the Ohio River near Moscow, Ohio. Over three years ago, the Cincinnati Gas & Electric Company was confronted with the need to implement new nuclear power plant computer systems. These systems were required by new regulations stemming from the lessons learned from the Three Mile Island accident. The Cincinnati Gas & Electric Company adopted a program to assure that these new systems conformed to continuity guidelines to realize efficient integration of hardware, software, and data when all computer systems are installed. Throughout this article, this program is referred to as the Station Information Management (SIM)concept. Computerized functions which are currently in place include Records Manage- ment, Plant Equipment Management, and in response to NUREG 0696, Emergency Response Facilities. Systems which are planned, or in the first stages of implementation are Reactor Core Monitoring, a Process Computer upgrade, and a Large Area Radia- tion Dose Evaluation System. This article outlines the information management philosophy which has been adopted at the Zimmer Station and gives a historical perspective on the information management needs and circumstances which fostered the SIM concept. Details of two computer systems which are in place (Records and Information Management, and Emergency Response Facility) are given. An overview of the SI M concept as it currently stands is presented. Finally, future com- puter system plans are presented along with the mechanisms that will assure their successful integration. 2. BACKGROUND AND REGULATORY REQUIREMENTS As early as 1978, the management of the Cincinnati Gas & Electric Company saw the need for the development of a comprehensive computerized in- formation management system for the Zimmer Station. The NRC, at that time, issued strong regu- latory requirements pertaining to the control of design, construction, and operating records at nuclear power plants. Many nuclear plants had implemented com- puterized records systems and were attempting to expand the records systems to total information management systems with varying degrees of success. These early attempts at total station information management integration were thwarted by a number of factors. Among these were: - -Lack of sufficient computer system expandability. - -Lack of up-front planning to assure efficient system integration. - -Lack of management coordination resulting in division of responsibilities for each software module. ~Changing regulations. --Resistance by many utility data processing depart- ments to allow an integrated minicomputer solution at nuclear stations. CG&E management realized the need for a system solution but also realized that a total solution would require a number of years to be practically put in place. A decision was made to adopt a modular approach to total system implementation which included the following concepts. 209 210 D. RILEY et al. 2.1. Expandable, flexibile minicomputer hardware The computer system hardware had to be expand- able to accommodate future growth. Minicomputers manufactured by Prime Computers Inc. and Digital Equipment Corp. were chosen as the preferred com- puter vendors. This was due to several factors includ- ing expandability, level of support available locally, industry acceptance, and use of those vendors equip- ment already within CG&E. Both manufacturers offered a series of Central Processing Unit (CPUs) with varying amounts of power and throughput. Each CPU was capable of handling a wide variety of peripheral devices and could be configured with large amounts of internal memory and user terminals. Furthermore, software written for a particular manu- facturer's CPU was upward compatible, and there was a corporate history of, and commitment to, continued upward compatibility. The choice of Prime hardware was facilitated by their extensive networking software and hardware which would allow for very flexible, easy to use, sharing of resources and enhanced data sharing between systems. The fact that the document control software already existed for Prime Computers, and that Reactor Core Monitoring software was being developed for Prime computers by Exxon Nuclear Corp. was also a strong consideration. The latter was important as CG&E will be using Exxon fuel starting with the first core reload. 2.2. Modular approach to system development It was clear that the total SIM concept was not going to be implemented at once. In fact, some computer applications for the Zimmer Station could not be anticipated. The approach taken was to specify guidelines for computer system development which would make system integration as efficient as possible. The guideline concept was not fully implemented when the first computer system (Records and Information Management) was installed, but was developed as more computer system were anticipated and procured. The guidelines include: --Selection of a computer vendor and system which support high level protocols such as CCITT X.25, and IBM HASP, for interface compatibility. --Process data acquisition will be performed by the Validyne HD-310 High Speed Data Acquisition System previously purchased and installed. --Al l applications should be written in a generally supported language such as Fortran '66 or Fortran '77. --Assembler Language routines should be used only where their avoidance is impracticable. --Al l project payment milestones should be depend- ant upon the receipt of project deliverables. --Detailed system functional descriptions, and pro- grammer specifications should be the first project deliverables so that CG&E can ensure the adequacy of the design, as well as form a basis for final system acceptance testing. 2.3. Formation of computer 9roup at the Zimmer Station In 1982, a separate computer group was formed at the Zimmer station to operate all station computer systems. This group also served as a liason organiz- ation with the engineering organizations concerned with Zimmer computer systems and as such attempts to assure computer system compatibility. 3. DOCUMENT RETRIEVAL SYSTEM PROCUREMENT AND IMPLEMENTATION In February of 1978 CG&E management hired General Physics Corporation to perform an evalu- ation of the document control requirements at the Wm. H. Zimmer Nuclear Power Station. The results of that evaluation indicated that a computerized docu- ment retrieval system was required. This was due to the large number of design and construction records which had been accumulated and the estimated number of records which would be generated in the future. The majority of these records had to be maintained, controlled, and made available to station management and engineers during the life of the Zimmer Station. These requirements and others are included in ANSI Standard N45.2.9, 'Document Control Standards for Nuclear Power Plants'. The document retrieval funcl!on was purchased as a part of a package which CG&E refers to as the Records and Information Management System (RIMS). This consists of various databases which are interconnected as appropriate. Databases which are, at least partially, in use at Zimmer are: Document Location Equipment Nameplate Data Work Item Tracking Surveillance Test Scheduling Preventive Maintenance Scheduling Equipment Spare Parts Equipment Work History Commitment Tracking Procedure Review Tracking Controlled Document Distribution An example of the interconnections between these Wm. H. Zimmer Nuclear Power Station 211 databases is the verification of component data for work requests from the Equipment Data database. Another example is the historical storage of work performed on a component or system by automatic transfer of data from the Work Item Tracking, Surveillance Test Scheduling, and Preventive Maintenance Scheduling databases to the Equipment Work History database. This transfer occurs upon the closeout of the work request, surveillance test, or preventive maintenance activity. In addition to the use by the station personnel, data from this system will be made available to the corporate reliability analysis group to allow for both NPRD reporting as well as feedback into analyses made using the Probabilistic Risk Assessment methodology. This will be done by producing an appropriately formatted magnetic tape to be read by the corporate mainframe computer for their use. 4. EMERGENCY RESPONSE FACILITY SYSTEM PROCUREMENT AND IMPLEMENTATION After the Three Mile Island incident, the NRC promulgated stricter regulations pertaining to the diagnosis and mitigation of accidents or upset con- ditions at nuclear power facilities. In the fall of 1980 the Commission issued a draft version of NUREG 0696 entitled 'Functional Criteria for Emergency Response Facilities'. This document recommended that every nuclear plant install or activate five facilities, which combined, would improve the utility personnel's ability to deal with such events. These facilities are a Technical Support Center (TSC), Safety Parameter Display System (SPDS), Operational Support Center (OSC), Emergency Operations Facility (EOF), and a Nuclear Data Link (NDL). The TSC and OSCs are located within the station security boundary, while the EOF is located away from the plant site. The Nuclear Data Link was to be a computerized transfer of plant data to the NRC in Bethesda, Maryland. In the fall of 1980, Zimmer fuel load was scheduled for the fourth quarter of 1981. This gave CG&E management only one year to implement the portions of NUREG 0696 that the Commission required. Licensing commitments required CG&E to demon- strate working TSC, SPDS, EOF and OSCs prior to receipt of an operating license. Accordingly, in October 1980 CG&E management authorized the issuance of a Request for Quotation for the develop- ment and installation of the Data Acquisition and Display System software (DADS) for the use in the TSC and EOF. In order to maintain hardware continuity and to ensure integration of station com- puter systems, CG&E specified that the DADS was to be written in Fortran '77 on a Prime 750 computer system. CG&E also specified that a Validyne HD-310 high speed distributed data acquisition system would be utilized to acquire the process data needed by the system. The Validyne data acquisition system will subsequently become the source of all process data for other computer systems at Zimmer. As a part of the bid specification, payment mile- stones were required to be based on the receipt of project deliverables. The first payment milestones specified were the development and delivery of de- tailed system functional specifications, and program- mer specifications. By using this mechanism, CG&E was able to ensure that the system was being designed and developed properly, as well as providing criteria for final system acceptance testing. The General Physics Corporation was chosen to develop the DADS software. The immediate problem was to specify and bound the software capabilities in light of changing regulatory requirements. A team of General Physics and CG&E personnel worked for over a month to develop functional specifications for the software. For expedience, the software was func- tionally divided into data acquisition and data display portions. This allowed the programmer specifications to be developed and programming to begin on the data acquisition software. Final decisions on data display software were postponed for three months until regulatory requirements became clearer, especially with respect to screen displays in the TSC and main control room. Since the SPDS required a subset of the data being acquired in the DADS, it was decided that the SPDS should be a subsystem of DADS. In light of their work for NSAC on NSAC 21, 'Fundamental Safety Parameter Set for Boiling Water Reactors', S. Levy Inc. was chosen to develop parameter validation al- gorithms and SPDS displays for integration into the DADS. They were provided with data acquisition system software interface descriptions, which they utilized to develop their software. The following project responsibilities were assigned with respect to the DADS software project. -~G&E would be responsible for overall project management. ~General Physics Corporation would be responsible for DADS software development and overall system integration. - -SPDS validation algorithms and screen displays would be developed by S. Levy Inc. and integrated with the General Physics data acquisition and display software. 212 D. RILEY et al. --Sargent and Lundy (Zimmer's Architect Engineer) would be responsible for providing all schematics, wiring diagrams, installation drawings, etc., re- quired for the acquisition of the signals which would be available in the DADS. There are several major features of the data acquisition software. They include the ability to handle real-time and historical databases concurrently, the ability to store at least 24-hr worth of plant data on both a primary and a back-up storage device, as well as a supervisor program which monitors the operations of all other programs and assures that the data acquisition functions do not fall behind by either changing system priorities, or even restarting pro- grams as required. The frequency of data collection was specified to be variable, that is that the sampling interval could be varied anywhere from 2 msec to 24 hr. Various studies were performed and it was decided that a sampling interval of 5 sec would be the best trade off between speed of data acquisition and data storage capability. As the summer of 1981 began two facts became clear, (1) the Zimmer Station would not be starting up in the first quarter of 1982 and (2) data acquisition software development and testing was falling behind schedule, mostly due to delays associated with receiving a production version of the various components in the Validyne data acquisition system, and the interfacing of the Validyne to the Prime 750. All parties subse- quently agreed to push the schedule for software com- pletion back approximately six months and to add some capabilities to the software which had not been originally planned. The most significant addition was to allow the software to drive a Containment Isolation Valve Status Mimic located in the main control room. This was accomplished using a CAMAC interface provided by Kinetic Systems Inc. By using the IEEE CAMAC standard, CG&E was able to purchase off- the-shelf digital output equipment with assurance that it would interface with the Prime computer and that any number of additional digital outputs could be added if needed. Another advantage to using the CAMAC equipment is the ability of other computer systems to interface to it. By April of 1982, most of the software was completed and preparations were begun for complete system integration and final testing in Columbia, Maryland. SPDS software installation was performed with minimal difficulties and by July of 1982 the final system testing had begun in Columbia, Maryland. The system was accepted by CG&E in August of 1982 and was shipped to the Zimmer Station in that same month. 5. CURRENT STATUS AND FUTURE COMPUTER SYSTEM PLANS The current start-up date for the Zimmer Station is the fourth quarter of 1984. At this time the design and engineering work necessary to the acquisition and installation of three new computer systems is proceed- ing. These are the enhanced process computer, Reactor Core Monitoring Computer, and a Zimmer specific simulator. In addition, work is proceeding to allow the simulator to provide data to the DADS system. This would allow the operator to see how the SPDS would function during the various transients being simulated, as well as allowing for the prior checkout of new displays, new validation algorithms, etc. Due to the design of the DADS software the real-time data collection and display effort is independent of the simulator data input, so that both functions will run concurrently. 6. CONCLUSIONS Because CG&E management has embarked upon a course of long range planning with respect to com- puter system design and development, the Zimmer Station will have a useful set of databases and computerized tools available to it for the foreseeable future. While all planned systems are not fully implemented, the systems which are in place are providing necessary information to the station oper- ators which save time and manpower. The approach adopted by CG&E management demonstrates that it is possible to successfully procure and install large, complex computer systems in stages if proper planning is employed.