Susceptibility of digital instrumentation and control systems to disruption by electromagnetic interference

摘要

The potential for disruption of safety-related digital instrumentation and control (I and C) systems by electromagnetic interference/radio-frequency interface (EMI/RFI) bears directly on the safe operation of advanced reactors. It is anticipated that the use of digital I and C equipment for safety and control functions will be substantially greater for advanced reactor designs than for current-generation nuclear reactors, which primarily use analog I and C equipment. In the absence of significant operational experience, the best available indication of the potential vulnerability of advanced digital safety systems to EMI/RFI comes from environmental testing of an experimental digital safety channel (EDSC) by the Oak Ridge National Laboratory (ORNL). The EDSC is a prototypical system representative of advanced reactor safety system designs with regard to architecture, functionality and communication protocols, and board and component fabrication technologies. An understanding of the electromagnetic environment to be expected for advanced reactors can be drawn from ORNL's survey of ambient EMI/RFI conditions in the current generation of nuclear power plants. A summary of the results from these research efforts is reported in this paper. The lessons learned from the EMI/RFI survey and the EDSC tests contribute significantly to determining the best approach to assuring electromagnetic compatibility for the safety-related I and C systems of advanced reactors.