Survey of Ambient Electromagnetic and Radio-Frequency Interference Levels in Nuclear Power ...

116 Pages·2005·2.12 MB·English

NUREG/CR-6436
ORNL/TM-13171
Survey of Ambient Electromagnetic
and Radio-Frequency Interference
Levels in Nuclear Power Plants
Manuscript Completed: October 1996
Date Published: November 1996
Prepared by
S. W. Kercel, M. R. Moore, E. D. Blakeman,
P. D. Ewing, R. T. Wood
Oak Ridge National Laboratory
Managed by Lockheed Martin Energy Research Corporation
P.O. Box 2008
Oak Ridge, TN 37831-6010
C. Antonescu, NRC Project Manager
Prepared for
Division of Systems Technology
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001
NRC Job Code L1951
DISCLAIMER
Portions of this document may be iUegible
in electronic image products. Images are
produced from the best available original
document
DISCLAIMER
This report was prepared as an account of work sponsored by an agency of the United
States Government Neither the United States Government nor any agency thereof, nor
any of their employees, make any warranty, express or implied, or assumes any legal liabili-
ty or responsibility for the accuracy, completeness, or usefulness of any information, appa-
ratus, product, or process disclosed, or represents that its use would not infringe privately
owned rights. Reference herein to any specific commercial product, process, or service by
trade name, trademark, manufacturer, or otherwise does not necessarily constitute or
imply its endorsement, recommendation, or favoring by the United States Government or
any agency thereof. The views and opinions of authors expressed herein do not necessar-
ily state or reflect those of the United States Government or any agency thereof.
ABSTRACT
This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear
power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research
engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the
electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in
nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended
observations. The data presented in this report were measured at eight different nuclear units and required 14
months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site
location) monitored over extended observation periods (up to 5 weeks) were selected to more completely
determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields
were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI
events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the
electromagnetic ambient environment across all measurement conditions at each site provide frequency-
dependent profiles for EMI/RFI levels in nuclear power plants.
NUREG/CR-6436
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CONTENTS
Page
ABSTRACT iii
LIST OF FIGURES vii
LIST OF TABLES ix
EXECUTIVE SUMMARY xi
ACKNOWLEDGMENTS xiii
ACRONYMS xv
1 INTRODUCTION 1
1.1 Motivation 1
1.2 Survey Approach 2
1.3 Units of Measure 4
2 SPECTRAL RECEIVERS 7
2.1 Design Requirements 7
2.2 Electric Spectral Receiver 7
2.3 Magnetic Spectral Receiver 10
2.4 Interpretation of Output Data 13
2.4.1 Electric Spectral Receiver 14
2.4.2 Magnetic Spectral Receiver 20
2.4.3 Presentation of Results 26
2.4.4 Precision and Uncertainty 28
3 OBSERVATIONS: BOUNDING VALUES 33
3.1 Survey Sites 33
3.2 Radiated Electric Fields 33
3.3 Radiated Magnetic Fields 38
3.4 Conducted EMI Events 38
4 OBSERVATIONS: COMPARISON BY CONDITIONS 43
4.1 Radiated Electric Fields 43
4.2 Radiated Magnetic Fields 52
4.3 Assessment of Variations 62
5 RATE OF OCCURRENCE 63
5.1 How Often Does It Happen? 63
5.2 Rates of Occurrence at Lower Field Strengths 63
5.3 Occurrences as a Function of Time 70
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5.4 How Long Is Long Enough? 74
5.5 Nonstationarity 80
CONCLUSIONS 83
6.1 Bounding Envelopes of Observed Levels 83
6.2 General Conclusions from the Survey Findings 89
6.3 Impact 89
REFERENCES , 91
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LIST OF FIGURES
Figure 1.1 Disruption of microprocessor state by electromagnetic noise 3
Figure 2.1 Block diagram of the electric spectral receiver 8
Figure 2.2 Electric spectral receiver physical layout 9
Figure 2.3 External view of the electric spectral receiver 9
Figure 2.4 Block diagram of the magnetic spectral receiver 11
Figure 2.5 Magnetic spectral receiver physical layout 12
Figure 2.6 External view of the magnetic spectral receiver 12
Figure 2.7 Electric spectral receiver interleaved subbands 16
Figure 2.8 Electric spectral receiver calibration curves 17
Figure 2.9 Strength bin structure for the electric spectral receiver 19
Figure 2.10 Simultaneous response of electric and magnetic spectral receivers 21
Figure 2.11 Magnetic spectral receiver calibration curves 22
Figure 2.12 Strength bin structure for the magnetic spectral receiver (radiated fields) 24
Figure 2.13 Comparative rates of occurrence 25
Figure 2.14 Strength bin structure for the magnetic spectral receiver (conducted events) 27
Figure 3.1 Nominal bounding values of observed radiated electric fields 37
Figure 3.2 Nominal bounding values of observed radiated magnetic fields 40
Figure 3.3 Nominal bounding values of observed conducted EMI events 42
Figure 4.1 Nominal bounding values of observed radiated electric fields
by operating mode 48
Figure 4.2 Nominal bounding values of observed radiated electric fields by reactor type 49
Figure 4.3 Nominal bounding values of observed radiated electric fields
by reactor manufacturer 50
Figure 4.4 Nominal bounding values of observed radiated electric fields by location 51
Figure 4.5 Nominal bounding values of observed radiated magnetic fields
by operating mode 58
Figure 4.6 Nominal bounding values of observed radiated magnetic fields by reactor type 59
Figure 4.7 Nominal bounding values of observed radiated magnetic fields
by reactor manufacturer 60
Figure 4.8 Nominal bounding values of observed radiated magnetic fields by location 61
Figure 5.1 Distribution of radiated electric field by strength and frequency 67
Figure 5.2 Distribution of radiated magnetic field by strength and frequency 68
Figure 5.3 Distribution of conducted EMI events by strength and frequency 69
Figure 5.4 Variation of radiated electric field over time 71
Figure 5.5 Variation of radiated magnetic field over time 72
Figure 5.6 Variation of conducted EMI events over time 73
Figure 5.7 Probability of duplicating the maximal observation 79
Figure 5.8 Time distribution of record 1 averages (block" size = 1024) 81
Figure 5.9 Time distribution of record 1 averages (block size = 64) 81
Figure 5.10 Time distribution of record 2 averages (block size = 1024) 82
Figure 5.11 Time distribution of record 2 averages (block size = 64) 82
Figure 6.1 Bounding envelope—radiated electric fields 84
Figure 6.2 Bounding envelope—radiated magnetic fields 86
Figure 6.3 Bounding envelope—conducted EMI events 88
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LIST OF TABLES
Table2.1 Electric spectral receiver frequency bins 15
Table 2.2 Observation uncertainty—radiated electric fields 30
Table2.3 Observation uncertainty—radiated magnetic fields 31
Table2.4 Observation uncertainty—conducted EMI events 32
Table3.1 Survey sites 34
Table3.2 Nominal bounding values of observed radiated electric fields 36
Table3.3 Nominal bounding values of observed radiated magnetic fields 39
Table3.4 Nominal bounding values of observed conducted EMI events 41
Table 4.1 Nominal bounding values of observed radiated electric fields
by operating mode 44
Table4.2 Nominal bounding values of observed radiated electric fields by reactor type 45
Table4.3 Nominal bounding values of observed radiated electric fields
by reactor manufacturer 46
Table4.4 Nominal bounding values of observed radiated electric fields by location 47
Table4.5 Nominal bounding values of observed radiated magnetic fields
by operating mode 53
Table 4.6 Nominal bounding values of observed radiated magnetic fields by reactor type 54
Table 4.7 Nominal bounding values of observed radiated magnetic fields
by reactor manufacturer 55
Table4.8 Nominal bounding values of observed radiated magnetic fields by location 56
Table5.1 Overall rate-of-occurrence histogram for radiated electric fields 64
Table5.2 Overall rate-of-occurrence histogram for radiated magnetic fields 65
Table5.3 Overall rate-of-occurrence histogram for conducted EMI events 66
Table5.4 Maximum amplitude statistical summary for electric field data 76
Table5.5 Maximum amplitude statistical summary for magnetic field data 78
Table6.1 Bounding envelope—radiated electric fields 83
Table6.2 Bounding envelope—radiated magnetic fields 85
Table6.3 Bounding envelope—conducted EMI events 87
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