Serving the energy industry for over 30 years
By - Danielle Duignan

Distribution Neutral Grounding and Stray Voltage
September 19-20, 2016 | San Diego, CA

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Overview

Grounding is one of the most misunderstood areas of distribution engineering. Although good grounding is generally helpful, sometimes improving grounds does little – if anything – to improve system performance, and it may actually have a negative effect. With the widespread addition of renewable and conventional distributed generation, it is important for the practicing engineer to understand the effects of grounding these sources will have on the distribution system. The meaning of the term “stray voltage” is also confusing to some, and is costing the industry millions of dollars in litigation. The purpose of this two-day course is to give the distribution engineer an understanding of the common methods of grounding, when they are commonly used and why, how they are designed and installed, as well as to address current concerns with stray voltage

Learning Outcomes

    • Review distribution systems, including voltage levels, substation and feeder design, equipment ratings and protection philosophies
    • Review basic concepts, including Earth as a conductor, mathematical models, step and touch potentials and the impact of good grounding on stray voltage
    • Describe system grounding choices and grounding criteria
    • Assess substation grounding, including reasons for substation grounding, permissible body current limits, step and touch voltages, use of IEEE Std. 80, and substation fence grounding
    • Describe grounding standards and practices
    • Demonstrate system grounding principals
    • Evaluate the effect of grounding on abnormal voltages, overcurrent protection, lightning and overvoltage protection and electromagnetic interference
    • Analyze the causes and effects of stray voltage and mitigation techniques
    • Analyze the effects of grounding on renewable and conventional generation and power production facilities

Credits

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EUCI has been accredited as an Authorized Provider by the International Association for Continuing Education and Training (IACET).  In obtaining this accreditation, EUCI has demonstrated that it  complies with the ANSI/IACET Standard which is recognized internationally as a standard of good practice. As a result of their Authorized Provider status, EUCI is authorized to offer IACET CEUs for its programs that qualify under the ANSI/IACET Standard.

EUCI is authorized by IACET to offer 1.0 credits for this event.

Agenda

Monday, September 19, 2016

Registration and Continental Breakfast: 8:00 – 8:30 a.m.

Course Timing: 8:30 a.m. – 4:30 p.m.

Group Luncheon: 12:00 – 1:00 p.m.

Distribution System Overview
  • Voltage levels
  • Substation design
  • Feeder designs
  • Equipment ratings
  • Protection philosophies
Basic Concepts
  • Earth as a conductor
  • General requirements
  • Mathematical models (Carson’s formulas)
  • Ground fault voltage and current calculations (symmetrical components review)
  • Step and touch potentials
  • Impact of good grounding on safety
System Grounding Classifications
  • Definition
  • Characteristics
  • Ungrounded systems
  • Low resistance grounded systems
  • High resistive grounded systems
  • Solidly grounded systems
  • Effectively grounded systems
  • Multi-grounded systems and stray voltage
Substation Grounding
  • Reasons for substation grounding
  • Permissible body current limits
  • Step and touch voltages
  • Ground grid design using IEEE Std. 80
  • Substation fence grounding
Distributed Generation Grounding
  • Conventional generator grounding (synchronous generator)
  • Renewable power plant grounding (solar, wind, fuel cell, microturbine)
  • Use of grounding transformers in power plant grounding
  • Grounding effect on harmonic current flow

Tuesday, September 20, 2016

Continental Breakfast: 7:30 – 8:00 a.m.

Course Timing: 8:00 a.m. – 4:00 p.m.

Group Luncheon: 12:00 – 1:00 p.m.

Grounding Standards and Practices
  • Neutral grounding rules
  • Substation grounding rules and calculations
  • Ground electrode rules and calculations
  • Pole grounds
  • Concrete foundations as pole grounds
  • Customer grounds as require by the National Electrical Code
  • Underground grounds
  • Metallic pipe grounds
  • Arrester grounds
Ground Resistance Testing
  • Soil resistivity testing
  • Four-point resistivity measurements (Wenner and Schlumberger-Palmer Methods)
  • Grounding electrodes
  • Ground resistance values
  • Ground electrode resistance testing methods (fall of potential and clamp-on methods)
  • Stray voltage measurements
  • Touch potential
Effect of Grounding on Swells
  • System temporary overvoltages
  • Effect of neutral wire size
  • Swell levels
  • Division of current
  • Effect of number of grounds
  • Effect of fault resistance
  • Effect of broken neutral
  • Effect of ground mat
Effect of Grounding on Overcurrent Protection
  • Impact of neutral conductor
  • Fault impedance
  • Effect of the multi-grounded system
  • Special protection problems with distributed generation
  • Effect on fault current levels
Effect of Grounding on Lightning and Overvoltage Protection
  • TOV
  • System overvoltages
  • Capacitor switching
  • Ferroresonance
  • Line protection
Stray Voltage
  • Causes
  • Effects on humans and animals
  • Mitigation techniques
  • Definition and cause of stray voltages
Impact of Grounding on Electromagnetic Fields
  • Cause of magnetic fields
  • Effect of ground current flow
Special Considerations
  • European systems
  • Grounding sensitive equipment
  • Maintenance grounding

Instructor

Keith Malmedal Ph.D, P.E. P.Eng,  Senior Member, IEEE

Keith Malmedal has over 25 years combined experience in electrical power system design and system study, teaching, and research, and is presently the President of NEI Electric Power Engineering, Arvada, Colorado.  He has published over 30 technical papers in subjects ranging from system grounding to distributed generation.  He holds masters degrees in both electrical and civil engineering and his Ph.D research at the Colorado School of Mines was on the effects of renewable energy distributed generation on existing distribution systems in the United States.  He teaches undergraduate and graduate classes at Metropolitan State University of Denver and the University of Colorado at Denver, and has taught short courses related to power systems, machines, protection, renewable energy, and energy policy issues for various IEEE chapters and conferences.

Location

San Diego Marriott La Jolla

4240 La Jolla Village Dr.
La Jolla, CA 92037

To reserve your room, please call 1-858-587-1414
Please indicate that you are with the EUCI group to receive the group rate.

Room Rate:

The room rate is $169.00 single or double plus applicable taxes.

Room Block Dates:

A room block has been reserved for the nights of September 18 – 19, 2016.

Rate Available Until:

Make your reservations prior to August 18, 2016. There are a limited number of rooms available at the conference rate. Please make your reservations early.

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