Electromagnetic Coordination Study Objectives for Railroad and Electric Utility Shared Corridors Eilis M. Logan UPRR Marvin J. Frazier Corr. Comp Co.
Electromagnetic Interference Magnet and Paper Clip Field Rather than Circuit View Point Passive Conductors - Rails Vital Signals - Railroad Systems
Electromagnetic Interference Coexist Simultaneously Source - Electric & Magnetic Fields Coupling Mechanism Receptor May Be Susceptible
Electromagnetic Interference Source - Power System Coupling Paths: Capacitive, Conductive, Inductive Susceptible Receptor - Railroad
Discussion Coupling Mechanisms Power System Influence Railroad Personnel Safety Criteria Equipment Compatibility Electrical Coordination Process
Coupling Mechanisms Capacitive - Electrostatic Personnel Safety Pole line, Crossing Gate, Signal Light Structures Conductive - Fault & Other Short Duration Conditions Personnel Safety & Equipment Compatibility High Local Earth Surface Potentials Magnetic - Inductive Personnel Safety & Equipment Compatibility Significant - Paralleling Power Line and Rails
Power System Influence Two Operating Conditions Steady-State - Normal Conditions Magnetic & Electrostatic Coupling Personnel Safety - Conductor-to-Earth Voltages Equipment Compatibility - Conductor-to-Conductor Voltages
Power System Influence Two Operating Conditions Fault and Other Short Duration Conditions Magnetic & Conductive Personnel Safety - Step & Touch Rails, Rolling Stock, Track-side Housing Equipment Compatibility - Rail Current - Surge Arrester Rating
Railroad Personnel Safety Signal and Track Maintenance Conductor-to-Earth Different Levels Are Acceptable Steady-State Fault or Short Duration
Railroad Personnel Safety Three Classifications Threshold - Tingling Startle - Annoying - Not Harmful Primary Shocks - 99.5% Voluntarily Let-Go Ventricular Fibrillation
Railroad Personnel Safety Conductor-to-Earth Objective Based on Primary Shocks: Minimize the Chance Power System Steady-State - Body Current Higher than Let Go Power System Fault - Ventricular Fibrillation
Railroad Personnel Safety Steady-State Operation Region of Electric Field Analyzed by the Shock Current NESC = 5 ma ac rms General Population Including Children Railroad Facilities Capacitive Induction NESC = 5 ma ac rms
Railroad Personnel Safety Steady-State Operation Conductor-to-Earth 25V Rail-to-Ground Each Side of Insulated Joints Rail Cut Locations Slide Fence Conductor Pole Line Conductor Underground Cable, Conductor, Metallic Shield
Railroad Personnel Safety IEEE Std 80 Safety Guide AC Substation Grounding Design Work Safely Around Substation Touch Voltage Hand-to-Feet Touching an Energized Object Step Voltage Between Feet Elevated Earth Surface Potential
Railroad Personnel Safety Power System Fault & Short Duration Conditions Hand-to-Feet Hand-to-Feet Near Near Earth Earth Signal Signal Houses Houses Rail Rail -- Railroad Railroad Work Work Zones Zones 25 25 Feet Feet Center Center Track Track By By Hand Hand or or Object Object Electrically Electrically Connected Connected to to Rail Rail
Railroad Personnel Safety Power System Fault & Short Duration Conditions Hand-to-Feet Hand-to-Feet Near Near Earth Earth Insulated Insulated Joints Joints Rail Rail Cut Cut Locations Locations Hand-to-Hand Hand-to-Hand Insulated Insulated Joints Joints Rail Rail Cut Cut Locations Locations
Railroad Personnel Safety Substation - Railroad Different Environments Substations Enclosed - Chain Link Fence Employees Aware Hazards Electrical Characteristics Inspected & Tested
Railroad Personnel Safety Application IEEE Std 80 Railroad Environment Reevaluation of Parameters Assess Safe Touch & Step Resistive Stone Covering not Ballast Region Protected - Railroad Work Zones Size of a Person - Body Impedance & Weight
Railroad Personnel Safety Application IEEE Std 80 Railroad Environment Ballast Resistivity Railroad Work Zone Electrical Characteristics Not Specified Ballast may not be Present Rotating Ballast Regulator 180-17 ft Disturb or Remove During Maintenance
Railroad Personnel Safety Application IEEE Std 80 Railroad Environment Body Impedance Railroad 24 hours a Day, 7 days a Week All Weather Conditions No Insulating Properties of Shoes or Gloves Standing in Bare Moistened Feet Per Std 80-1000 ohms Body Impedance
Railroad Personnel Safety Application IEEE Std 80 Railroad Environment - Body Weight IEEE Std 80 used United States IEEE Std 80 Considers Size - Weight Railroad Operational & Construction Criteria Smaller Sized Person - UPRR Railroad Occupational Safety = 100 LB
Equipment Compatibility Equipment Compatibility -- Susceptibility Signal System -- Abnormal Operation False Activation or Activation Failure Different Types -- Different Levels Power System Steady-State & Fault
Equipment Compatibility Power System Steady-State Operation 60 Hz & Harmonics Voltage and Current Must be Less Than Tolerance Level Equal Excitation Paired Conductors Day-to-Day Unbalance Conditions Nearby Power Line Differential Voltage
Equipment Compatibility Maximum Steady-State Operation Coupled Conductor-to-Conductor for UPRR Balanced Track Conditions Shorted Insulated Joint Electrically Broken Rail, Conductor Grounded Rail, Conductor Presence of a Train
Equipment Compatibility Power Line Fault Conditions Rail-to-Near Earth Potentials With and Without Arresters Operation AREMA Performance Guidelines Lightning Wave Form - Short Duration Power Line Fault Wave Form - Long Duration Rail Current Less Than Arrester Rating Based on Power System Fault Clearing Times
Electrical Coordination - Process Electromagnetic Coordination Study Resolve Interference Problems Location, Design, Construction, Operation & Maintenance of Power & Railroad Systems Three Phases
Electrical Coordination - Process Phase 1 Meeting Railroad, Utility, Consultant Scope of Investigation Acceptable Mitigation Modeling Assumptions Design Criteria
Electrical Coordination - Process Phase 2 - Generate Study Railroad & Power System Data Public & Personnel Safety Criteria Equipment Impedance & Susceptibility Data Computer Models - Steady-State & Fault Mitigation Design - Limit Coupled Voltages
Electrical Coordination - Process Phase 3 - Approval Power Utility Company Railroad Equipment Supplier Railroad Finance Operating & Engineering
Summary - Electromagnetic Study Defines Physical & Electrical Parameters Provide Predictive Assessment of Coupled Voltages & Currents Power System Conditions Steady-State & Fault Personnel Safety Equipment Compatibility Mitigation
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