INDUSTRY NEED

Power transmission owners and operators need to develop new line designs and to find ways of increasing the capacity of existing lines that are acceptable to the public, reliable, and which re-quire only modest capital investment. Long lead times for new lines, limited availability of right-of-way, and increasingly complex procedures for applications and permits justify increased sophistication in making lines that are more compact yet capable of higher power flow levels. 

COURSE OBJECTIVE AND SUMMARY

This course addresses traditional and novel methods and materials for maximizing power flow on new and existing transmission lines. It explores the tradeoffs between reducing visual impact and operational reliability, between capital investment and increased power flow. Both electrical and mechanical aspects of line design and modification are covered within a framework of making smart economic choices. Both experienced designers and beginning engineers can profit from the presentations. Some topics related to underground cables are included.

PDC has identified learning objectives we expect each student to obtain on completion of this course.  The student completing this course should be able to:

1. Identify the main components of an overhead power transmission line.
2. List and briefly describe the power system constraints that may apply to a transmission line.
3. Describe in general terms the relationships between sag, tension, line loading and operating temperature.
4. List the basic environmental issues associated with transmission lines.
5. Understand the basic requirements for overhead line ratings.
   

WHO SHOULD ATTEND

The course will be valuable to engineers responsible for planning, operating or designing transmission circuits.  

PREREQUISITES

An engineering degree in mechanical, electrical or civil engineering is desirable.

MONDAY – LINE DESIGN OVERVIEW

• Introductions & Discussion
• Introduction to Line Design
  - Historical Development of T Lines
  - Examples of Common Designs
  - Main Components of Lines
  - Recent Trends
  - Uprating vs. New Line Design

    Break

• Power System Constraints
  - Thermal Limit
  - Voltage Drop
  - Phase Shift Stability

• Insulator Types
  - Post and Tension Insulators
  - Porcelain and Non-ceramic Insulators

• In-Span Insulating Spacers

• Power Frequency Insulation
  - Clearances to Structures
  - Contamination
  - Leakage Distance
  - Insulator Surfaces
  - Design of Insulator Skirts

    Lunch

• Lightning
  - Back flashovers
  - Shielding Failures
  - Traveling Waves
  - Footing Resistance
  - Coupling of Shield and Phase Conductors

    Break

• Conductor Design
  - Aluminum, Copper and steel wires
  - Stranded Conductor Designs
  - ACSR Stranding Alternatives
  - Trapezoidal Aluminum Wires
  - Special Conductors
  - Phase Conductor Selection
  - Shield Wire Choices

TUESDAY – CATENARIES, RATINGS & WIND

• Sag-tension Considerations
  - The catenary: sag vs. tension
  - Conductor Length & Slack
  - Inclined spans
  - Wind & Ice Loads
  - Sag at high temperature

    Break

• Tension Limits
  - Unloaded Tension Limits
  - Standard Tension Limits
  - Extreme Loading Limits
• Ruling span concept
  - Coupled suspension spans
  - Ruling span definition
  - Stringing sag tables
  - Ruling Span Errors
• Stringing conductor
  - Slack stringing
  - Tension Stringing
• Conductor Sagging
  - Transit methods
  - Tension methods
  - Stopwatch technique

    Lunch

• Wind-Induced conductor Motions
  - Blowout
  - Insulator Swing
  - Aeolian Vibration
  - Vibration Dampers
  - Ice galloping & control methods
  - Sub-conductor motions

    Break

• Thermal Ratings
  - Conductor Heat Balance
  - Steady State Normal Ratings
  - Transient Emergency Ratings
  - Weather Conditions
  - Annealing of Copper and Aluminum
  - Sag clearance at high temperature
  - High temperature creep elongation

WEDNESDAY – DESIGN & UPRATING 

    INSULATION/ELECTRICAL

• Environmental Effects
  - Criteria, Prediction and Evaluation
  - Exceedance Levels
• Electric Field
  - Field at Conductor Surface and Corona
  - Field at Ground Level and Coupling
  - Unperturbed and Perturbed Fields
  - Safety, Annoyance and Perception

    Break

• Magnetic Field
  - Maximum and Resultant Field
  - Inductive Coordination
  - Field Profiles
  - Problems Comparing Calculation to Measurement
• Corona:  Noise and Losses
  - Audible Noise
• Radio and Television Noise
  - Spark Discharges
  - Weather Dependence
  - Criteria
  - Signal strength
  - Signal to Noise Ratio

    Lunch

    DESIGN & UPRATING

• New Line Design Cost Issues
  - Present Worth of Electrical Losses
  - Conductor Material & Labor
  - Cost of Structures
  - Foundation Costs
  - ROW cost
  - Economic optimization
• Detailed Review of 115kV Line Design 
  - Design Constraints
  - Thermal Rating
  - Weight/Wind/Ruling spans
  - Blowout & ROW width
  - Calculating high temperature sag
  - Choosing a pole length
  - Selecting a pole strength
  - Lightning Shielding
  - Electric & Magnetic Fields
  - Noise & Interference
• Line Uprating
  - Power System Inputs
  - Normal vs. emergency power flow
  - Electrical Losses
  - Dynamic Rating Methods
  - Conductor Replacement
  - Structure Reinforcement
  - Use of higher conductor temperature
  - Hardware/Connectors

Typical classroom hours are 8:30AM to 4:30PM, with a continental breakfast starting a half hour before class time.  The instructors will take an informal survey of students on the first day to see if the classroom hours should be adjusted to accommodate travel schedules or other activities outside of class.

The three-day course will be held at the Alden Beach Resort, 5900 Gulf Boulevard, St. Pete Beach, Florida 33706.  A special rate is available to those attending PDC's course.  The rooms generally have two double beds, living room, and kitchenette.  Please contact the Alden Resort directly at 1-800-237-2530.  Mention the PDC course to obtain the lower rate.  Reservations must be made by 30 days in advance to insure the special rate.  Map of Area

Dr. Dale A. Douglass, Principal Engineer, with Power Delivery Consultants, has over 30 years experience with overhead line design, analysis, uprating and R&D.  Dr. Douglass will be the primary instructor for the course.

Dr. James R. Stewart, P.E., Consultant, has over 30 years experience with overhead lines, focusing on research and development projects including development of the first 6 and 12 phase transmission lines.  Dr. Stewart will present information on the electrical parameters of lines, environmental factors (fields, noise), and lightning.

Continuing Education Units

PDC is a Continuing Education Provider in the State of Florida (#CEP00180) and will issue students a course certificate indicating the number of Continuing Education Units for the course completed based on national guidelines and the number of classroom hours.  1.8 Continuing Education Units (CEUs) will be awarded for successful completion of this course.  The CEU is the nationally recognized unit for recording participation in noncredit educational programs.  One CEU is equal to ten classroom hours.

The tuition covers the cost for this five-day course and includes extensive course notes, continental breakfast and lunch.  Each participant will be furnished a bound set of notes.  Included will be an extensive bibliography and selected technical papers.   Lodging, transportation, and other meals are not included.