SBIR-STTR Award

Safety and reliability of control are foremost considerations for nuclear powerplants. As nuclear powerplant control becomes more distributed with next-generation intelligent sensors, integrated signal processors, and so forth, the need for more reliable plant-wide communication will become increasingly significant. Because the distributed communication system is the most exposed element in the overall control system, it is the most vulnerable to transient and steady-state radiation. Optical waveguides avoid electrical interference and offer superior overall safety and performance characteristics. However, they are also susceptible to nonrecoverable radiation-induced losses at low-dose radiation levels such as those commonly found in nuclear powerplant environments. During Phase I of this program, a functional design concept will be proposed for a universal communication device that would provide fault tolerant data transmission with integral, real-time optical power measurement and optical fault isolation capability. This would provide continuous real-time monitoring of optical power losses (radiation-induced and others) coincident with data communication throughout the fiber optic communication grid. Failure conditions could be predicted and dimensionally isolated to the precise location in the optical waveguide where the damage has occurred (or to the location of the failed transmitter or receiver). This would enable predictive maintenance with a high degree of safety, reliability, and efficiency.Anticipated Results/Potential Commercial Applications as described by the awarder:The anticipated result is improved overall reliability of fiber optic communication in nuclear powerplants by preventive maintenance through fault prediction and dimensional fault isolation. Potential commercial applications exist not only in local area networking and telecommunications but also in dedicated sensors and instruments. Fault prediction capability would add a much higher degree of reliability to local-area network communication systems where any loss of highly critical data transmission is unacceptable. Dimensional isolation of faults in long-line or telecommunications environments would help to efficiently determine the precise location of the failure through miles of conductors, to help expedite repair and minimize downtime. On-line optical power measurement for fault prediction and fault isolation provides a powerful diagnostic feature for minimizing communication downtime and mean-time-to-repair.

Nuclear power generating plants utilize distributed computers, controllers, and intelligent sensors for the assimilation and processing of data to assure safe, efficient operation. As these systems become increasingly complex and interdependent, they will require a fault tolerant, distributed communication system for interactive operation. These systems must be capable of reliable service in the nuclear industry. The distributed communication system is the most exposed and vulnerable element in the overall system. Nuclear power engineers are increasingly selecting optical waveguides for reliable, plant-wide local-area network communications and control sub-systems. Optical waveguides avoid electrical interference and offer superior safety and performance characteristics. However, they are also susceptible to gradual and nonrecoverable intrusive damage from low dose radiation levels, like those commonly found in nuclear power plant reactor containment buildings, radioactive waste processing buildings, and some nuclear power plant auxiliary buildings. In Phase I a concept and design methodology was developed for fault tolerant optical data transmission with integral, real time optical fault prediction and dimensional fault isolation capability. Through continuous, on-line monitoring of optical power losses (radiation induced and others), it was demonstrated that impending failure conditions can be predicted and dimensionally isolated before they occur enabling predictive maintenance with a high degree of safety, reliability, and efficiency. Phase II will provide detailed design, development, and implementation of the Phase I design methodology. An intelligent, general purpose optical fault tolerant, fault predictive communication interface (based on open architecture design) will be developed for nuclear power communication systems. An on-line computer link will be provided for continuous monitoring and logging of optical performance and offline trend analysis and fault modeling. Prototype units will be constructed and made available for beta site testing and validation. These fault tolerant, fault predictive modems will enable predictive maintenance, providing a communication environment in which impending communication failures are predicted, located, and corrected before they actually occur.Anticipated Results/Potential Commercial Applications as described by the awardee: The anticipated result is a demonstrated improvement in overall reliability of fiberoptic communication in nuclear environments by providing the means for pinpointed preventative maintenance through fault prediction and dimensional fault isolation. Promising applications exist in the commercial sector in industrial local-area networking, medical, and industrial CAT scanners, telecommunications, peripheral communication, and intelligent sensors and instrumentation, and in the government sector for fiber-optic applications on nuclear-powered submarines and surface ships.Topic 12: Sensors and Monitoring for Advanced Nuclear Reactors