CANDU PLANT COMPUTER SYSTEMS

Evolving and Replacing CANDU Plant Computer Systems

L3Harris has been supplying CANDU plant computer systems—known as L3Harris has provided DCC systems Digital Control Computer (DCC) systems — for nuclear power plants since for CANDU nuclear power plants 1970. In addition to keeping the DCC technology relevant for today’s in , , , Italy, Korea and Romania. Since 2006, we CANDU plants, L3Harris offers other CANDU plant I&C replacements and have been working with the CANDU CANDU plant simulator overhauls. Owners Group (COG) to enhance the DCC technology and documentation Through cooperation with CANDU scanner is connected to both DCC X and to serve as a reference for future DCC designer SNC-Lavalin, or directly with DCC Y, but communicates with only the projects. A current generation DCC power generation utilities, L3Harris has annunciating DCC. system resides at L3Harris’ main been supplying CANDU plant computer TECHNOLOGY BASIS Montréal, Canada facility and is used systems - known as Digital Control Computer to provide support to all participating (DCC) systems – for nuclear power plants The DCC system architecture is centered COG members until 2035. since 1970. DCC systems are used to on two technologies – the central monitor and control all the major reactor processing unit (CPU) and the I/O system. OUR CANDU CUSTOMERS and power plant functions. In response to The CPU technology has evolved from the ARGENTINA demand we have continued to upgrade the initial Varian 70 family of microcomputers technology over the last five decades. to the current Second Source Computers > Embalse Inc. (SSCI) CPU, first the SSCI-125 SYSTEM OVERVIEW CANADA generation and now the SSCI-890. The A typical system consists of two DCCs. I/O system is based on the Datapath 50 > Bruce A DCC X and DCC Y are redundant on-line data acquisition and the control system > Bruce B controllers, which control the nuclear technology is designed and manufactured > Candu Energy, a member of reactor. Each controller uses a computer to monitor andcontrol CANDU reactor SNC-Lavalin Group with a purpose-built process input/output units. Every consideration has been taken (I/O) system and peripherals housed in into account throughout all stages of > CANDU Owners Group cabinets, and utilize additional freestanding design and construction to ensure that the > Darlington peripherals such as keyboards, printers system operates with maximum efficiency > Gentilly-2 and monitors. A contact scanner is used and reliability. to scan relay contacts, limit switches, > Pickering A or other similar types of contacts. The > Pickering B > Point Lepreau CHINA > Qinshan Phase III KOREA > Wolsong ROMANIA > Cernavodă CPU PROGRESSION 128MB and provides for an extended L3HARRIS area of housing software applications and The SSCI-890 computer features a historical data storage buffers. The new REFURBISHMENT single board CPU, a cache board and technology of network printing – using fast 2MB memory modules. The CPU and ACTIVITIES FOR THE laser printers – required an adaptation of memory communicate over a special printer controllers for alarm messaging CANDU FLEET system connector plane that eliminates and hardcopy functions. inter-connect cables. The SSCI-890 DCC AND PERIPHERALS CPU includes mapped main memory. Committed to continuous improvement UPGRADES AND REPLACEMENT A map on the CPU board can perform of the DCC design, we have successfully > Full DCC system replacements efficient memory management for up to emulated the functionality of the Main sixteen million bytes of main memory Control Room Display System with > SSCI-890 CPU and controllers with full memory protection. The memory the use of its VME-based technology. upgrades and replacements modules combine 2MB of metal-oxide This emulation solution has resulted > DCC display system upgrades and semiconductor memory with error- in a complete replacement of Ramtek replacements correcting code on a single plug-in equipment while maintaining the same > PDP-11/D CPU and display controller module. DCC software developed by utilities upgrades and replacements and used on the original display system Along with the SSCI-based CPU hardware. > I/O system upgrades and architecture, we have supplied and replacements supported the PDP-11/70 DCC CPU The same VME-based technology was architecture. This implementation, the baseline of replacing the Contact > Contact scanner replacements in service for more than 15 years at Scanner equipment and presently this > DCC software development test Power Generation’s (OPG) implementation is in operation in both bench Darlington Nuclear Generating Station, units at the Qinshan Phase III Nuclear > Spare parts and services was the subject of an innovative L3Harris Power Project (Zhejiang, China) and on replacement through a fit, form, and Unit 2 at the Cernavoda Nuclear Power OTHER CANDU PLANT I&C function hardware emulation. Plant (Cernavoda, Romania). REPLACEMENTS

PERIPHERAL SYSTEMS AND LONG-TERM SUPPORT > Shutdown system trip computer INTERFACE CONTROLLERS UPDATES replacements Our goal is to ensure that COG and CANDU In addition to the continuous enhancement plant operators have a solid, reliable > Display/test computer replacements of CPU performance of the DCCs, we supplier on whom they can rely for their > Reactor regulating system logic have updated and re-designed several maintenance and support services. module replacements peripheral equipment and interface L3Harris has been supporting the DCC for > Other I&C system reverse controllers related to the data storage, nearly 50 years and is firmly committed to engineering replacements printing, and the data acquisition interface enhancing its support for the product line with PCs. The new bulk storage memory for the next 50 years. > Spare parts and services unit increases the total memory size to SIMULATOR OVERHAULS > Platform upgrades > Plant model modernizations > DCC emulations > Severe accident simulation > Control room panels and instrumentation > “Second” simulators > I/O system replacements > Spare parts and services

source: SNC-Lavalin CASE STUDIES

DARLINGTON SDS2 In support of the Darlington refurbishment program and OPG’s overall effort to design and develop a replacement for SDS2, L3Harris carried out the hardware design, integration and testing of prototype systems, including qualification testing, followed by the delivery of production units for the SDS2 trip computers and the SDS1 and SDS2 display/test computers.

BRUCE DCC TEST BENCH L3Harris successfully designed and delivered an SSCI-890 test bench comprising a CPU that is identical to those in the plant computers. The test bench is connected to the plant’s operator training simulator (or equivalent) to support development, testing and validation of new software programs for the plant DCC and DCC software changes.

BRUCE A & B DCC ALARM RECORDER To enhance the plant process operator Supervisory Control & Data Acquisition system and to modernize the storage and searching capabilities of the extensive information provided by the DCCs at Bruce A & B, L3Harris designed and developed a new alarm recorder system, which collects, streams and transfers the process data and alarms generated during plant operation. The alarm recorder system benefits from a highly performant interface controller (PCI-based parallel data link controller designed by L3Harris) connected to the DCCs. trademarks, registered trademarks, or trade names of their respective holders. respective their of names trade or trademarks, registered trademarks, are referenced names product and names brand other All Inc. MAPPS L3 of trademark aregistered is Orchid fuel. as uranium natural and coolant, and moderator the as water) (heavy oxide deuterium uses that adesign is system CANDU The Uranium. Deuterium CANada for acronym an is CANDU Group. SNC-Lavalin the of a member Inc., Energy Candu by license under used Limited, Canada of Energy Atomic of trademark aregistered is CANDU |03/2021 Inc. Technologies, L3Harris © 2021 Plant ComputerCANDU Systems source: SNC-Lavalin emulated DCC is used as a baseline to abaseline as is used DCC emulated The 6(EC6) MCR. CANDU Enhanced the to units represent display video multiple on enabled are panels soft interactive The emulation. DCC a dual and MCR the representing panels soft interactive with simulator is equipped The environment. simulation Orchid® leading industry- the by powered platform aPC/Windows on operating plant 6 real-timefull simulation of aCANDU a with SNC-Lavalin provided L3Harris EC6 ENGINEERING SIMULATOR objectives were met. were objectives to of SNC-Lavalin’s that ensure all provided were support and training In addition, Environment. Modeling Orchid® our in verified and modeled software control PES new with logic and programs control out change iteratively visit L3Harris.com visit fleetCANDU refurbishment capabilities, L3Harris’ on information more For MORE LEARN [email protected] t +1 514 |f+1 4999 787 1442 514 788 1G5 H4T Canada Québec, Montréal, 8565 Côte-de-Liesse

source: