Chapter 10 considers the Rod Group and Individual Control (RG&IC) system, which is one of the individual I&C systems and a part of the reactor control and protection system. RG&IC is an actuation system, which performs functions initiated by emergency and preventive reactor protection, reactor power control, unloading, limitation and accelerated preventive protection, and remote control rod position commands sent by the power unit personnel. The central part of RG&IC system consists of software-hardware complex SHC RG&IC-R based on the equipment family of the Research and Production Corporation “Radiy” (RADIY PLATFORM – see Chapter 1). The RG&IC system combines functions that belong to A and B categories according to safety impact (IEC, 2009), relates to safety class 2(A) and complies with the fundamental safety principles (IAEA, 1999), requirements that are set forth in international standards (IAEA, 2002, 2012; IEC, 2011), and Ukrainian nuclear safety rules and regulations (NP, 2000, 2008a, 2008b).
TopIntroduction
Modernization of rod group and individual control (RG&IC) systems at Ukrainian NPPs provides the replacement of out-of-date equipment of the central part with new software-hardware complexes, which are designed basing on positive domestic and foreign experience in compliance with the following main provisions:
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Preservation of the rod group and individual control functional purpose, algorithms, priorities of control functions and performance principles of control rod drives provided by the operational system;
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Preservation of the peripheral equipment (sensors of control rod position and control rod drives) used in the operational system;
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Preservation of operational system connections with other power unit I&C-systems: emergency and preventative reactor protection (E&PRP) system; reactor power control, unloading, limitation and accelerated preventive protection (RPwCUL&APP) system; in-core reactor monitoring (IRM) system; computer information system (CIS);
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Preservation or reduction of the existing cable lines;
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Improvement of application properties and operational durability (reliability, maintainability, availability) by using of modern information technologies, new electronic components produced by world leading manufacturers, industrial PCs, diagnostics, etc.;
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Compliance with requirements of nuclear and radiation safety rules and norms, obligatory requirements of any other Ukrainian standards and international standards requirements.
As a technical base of rod group and individual control system modernization on power unit 1 at South-Ukrainian NPP the designed Research and Production Corporation (RPC) “Radiy” software-hardware complex SHC RG&IC-R was accepted. The use of this complex for modernization of similar systems at the other South-Ukrainian NPP power units is provided.
SHC RG&IC-R is designed for work with the peripheral equipment (control rod drives and sensors of control rod position) of all types used at the Ukrainian NPPs.
All main SHC RG&IC-R functions (input signals transformation, logical operations performance, control algorithms realization, forming of controlling actions on control rod drives) and a range of auxiliary functions (diagnostics, etc.) are realized basing on field programmable gate arrays (FPGA), which electronic designs are developed and implemented by RPC “Radiy”, while in software-hardware complexes from other providers such functions are performed by microprocessor controllers and/or industrial PCs under system and application software. The use of FPGA provides high flexibility (adjustment to realization of different I&C functions) comparable to the computing hardware programmable means capabilities, and, at the same time, good predictability of behavior and testability of SHC RG&IC-R main functions, typical for the devices with unconditional logic (“hard-wired technology”). It decreases the risk of common cause failures, which can be caused by the errors during FPGA electronic design development, in comparison with the risk of possible hidden errors during computing operations programming. Besides, parallel (simultaneous) way of FPGA functions realization allowed to increase SHC RG&IC-R speed.
TopBackground
Chapter 8 provided information on way of neutron power control by moving of the absorbing rods in the reactor core and a short description of the system, which performs functions of rod group and individual control being a part of reactor control and protection system at the Ukrainian NPPs. In this Chapter the detailed information on the purpose, performed functions, technical specifications, composition, structure and software of the SHC RG&IC-R complex within the modernized RG&IC system at South-Ukrainian NPP unit 1 is provided, along with the assurance of its functional safety.
Information on control rod drives and sensors of control rod position is provided in this Chapter in quantity required for understanding of SHC RG&IC-R performance; detailed description, specifications and experience of using of such peripheral equipment is given in the book Nikituk, 2004.