January-February 2019 NPJ

(Continued on page 44) Josh Cole Mr. Joshua Cole serves as an Electrical Engineer in AMS’ electromagnetic compatibility (EMC) testing division. Mr. Cole is responsible for performing EMC testing and troubleshooting for customers in the nuclear industry. He has performed EMI/ RFI qualification testing of planned I&C upgrades in the AMS laboratory and in the field for numerous nuclear power plants using guidance specified by the U.S. Nuclear Regulatory Commission (NRC) and the Electric Power Research Institute (EPRI) as well as troubleshooting of emergent EMC issues for the U.S. nuclear fleet. He has also gathered site survey measurements for the electromagnetic emissions profile of nuclear power plants in support of these upgrades. Along with EMC qualification activities, Mr. Cole supports AMS’ research and development (R&D) projects to bring innovative new products and services to the nuclear industry. Some of these efforts include the development of test methods and systems to assist in the implementation of fixed and mobile wireless devices in nuclear facilities, in-depth studies on radiated emissions of cables installed in cable trays and the effectiveness of various grounding configurations of cable trays. In addition, he has provided condition monitoring testing and troubleshooting assistance with critical plant systems such as control rod drive mechanisms and rod position indication systems. Mr. Cole has performed laboratory testing to improve data acquisition and analysis equipment for field testing services and cable diagnostics. Operating Experience On January 26, 2012, an electrical fire occurred in the Unit 3 control room of the Browns Ferry Nuclear Power Plant in Alabama while the reactor was operating at full power. The failure of a capacitor in the power supply of an annunciator panel was determined to be the cause of the fire. This failure resulted in the loss of annunciator indication for that panel. Luckily, the fire was extinguished without a significant impact on plant operations. The failed capacitor would have probably manifested itself as an increase in amplitude of the electromagnetic emissions at the switching frequency of the power supply (in the range of 50 to 100 kHz) as well as its harmonics. These emissions could have been identified through non-intrusive measurements of the power supply output or the radiated emissions captured by an antenna near the annunciator panel. Another example of a failed electrical component causing significant disruption to power operation occurred on June 16, 2010 when two control rods were unintentionally dropped into the reactor causing a scram at Unit 1 of the St. Lucie Nuclear Power Plant in Florida. This failure led to a costly eleven-day outage to troubleshoot the issue. The investigation revealed failures of the resistor/capacitor (RC) networks in a power cabinet. These RC networks are responsible for preventing large voltage spikes generated by the power source from affecting the rod control circuitry. A system monitoring for the presence of large voltage transients could have provided an early warning of the failed RC networks. Table 1 presents additional examples of component failures in nuclear power plants as reported in the Licensee Event Report (LER) database maintained by the U.S. Nuclear Regu- latory Commission (NRC). Precursors to these events could be identified through condition monitor- ing using SECA. R&D Objectives A SECA unit will be developed and demonstrated under this R&D by execution of the following technical objectives: • Identify the most vulnerable electrical and I&C equipment of nuclear power plants and select a few to be used in SECA development. The focus of this effort will be on vulnerable equipment that are important to safety, availabil- ity, or efficiency of a nuclear power plant. • Measure the baseline emission char- acteristics of selected nuclear plant equipment and create a library of normal emissions spectrums. • Artificially degrade the selected equipment, measure the resulting emission spectrum, and compare it with the baseline spectrum. The purpose of this effort is to determine how equipment degradations Table 1. Representative LERs Related to Nuclear Plant Electrical and I&C Component Failures. Nuclear Plant Journal, January-February 2019 NuclearPlantJournal.com 43