Active Redundant Hardware Architecture for Increased Reliability in FPGA-Based Nuclear Reactors Critical Systems

Abstract

The hunt for increased reliability in systems for critical applications is a never-ending process and is a point of concern for designers in several different fields, such as nuclear reactors. This concern becomes more prominent when a new device technology is integrated into the options for the development of those systems, such as programmable logic devices like the FPGA. With the constant breakthroughs in this technology, there has been an increase in the capacity and the performance of FPGAs. Nevertheless, new methods to keep fault tolerance at an appropriate level for critical applications in hardware must be considered, particularly due to the transient nature of some radiation-induced faults. This work proposes a resilient and adaptable hardware architecture that increases the reliability of circuits implemented in FPGAs, based on a classic active redundancy model, Triple Modular Redundancy with spares. Also, it brings forth a novel hardware architecture that can easily be ported to different FPGA models without compromising performance, reliability, and availability. We discuss and analyze these requirements for the proposed architecture and show that it is more reliable and keeps this reliability for longer periods of time than redundant solutions that use more area.