UNDERSTANDING INSULATION OF HIGH VOLTAGE POWER TRANSMISSION AND DISTRIBUTION SYSTEMS


Lead Instructor (s):

Prof. Dr. Muhammad Akbar
PhD

Dates:

25-27 October 2017

Course Fee:

PKR 45,000/-


This course has limited enrollment. Apply early to guarantee your spot.


Course Summary

Seeing Pakistan’s energy scenario, the ever-growing demand for power generation and its transmission too far off load centers shall necessitate construction of more and more high-voltage transmission lines operating at extra high voltage levels. The right-of-ways of such future lines may bring new challenges of diverse environment which shall have direct bearing on their reliable operation. This aspect may become further stringent and dictating for future HVDC lines which are being considered as an economical alternative to HVAC. Electrical insulation is the backbone of all modern power system networks. Different types of dielectrics that constitute the insulation elements are subjected to a variety of electrical, mechanical and environmental stresses during the life span. The technical staff of operating utilities must efficiently tackle the complicated problems of insulation through first-hand knowledge of factors affecting insulation systems employed both for internal and external use for safe transfer of power over a long distance. The electrical manufacturing sector, while making products has to rely on insulation systems combining solid, liquid, gaseous, vacuum or polymeric insulation. It is desirable that failure mechanisms of such insulation are well known both for indoor and outdoor environment so that the insulation system of electrical power network could be optimally designed. Through specialized testing of insulation systems used both on power transmission and in the electrical equipment, one can make a reasonable assessment of the design adequacy and health conditions of employed insulation. A three-day workshop is planned to cover these topics through interactive sessions with participants while relating discussions to the operational problems at the user ends.

COURSE OBJECTIVES

The workshop shall be very interactive in character whereby at the end of the course the participants will be able to:

  • Know various types of insulation used in high voltage transmission and distribution systems and in the manufacturing of power equipment.
  • Understand the mechanisms of electrical breakdown in solid, liquid and gaseous dielectrics.
  • Understand the mechanisms of flashover of contaminated solid insulators and tracking of polymeric insulators.
  • Better understand anti-contamination design criteria and maintenance practices.
  • Understand the principles employed in insulation design of equipment such as cables, bushings, circuit breakers and overhead line insulators operating at high voltage so that they do not fail.
  • Be aware of principles of design and operation of high-voltage test equipment including AC, DC and impulse voltages and their measurements.
  • Understand various methods of insulation testing and their relevant international standards.
  • Understand methods available for health-monitoring of insulation systems, such as partial discharge level, dissolved gases in oil and C and Tanࢾ levels.
  • Better understand the needs of operation and maintenance of transmission and distribution system and its economic aspects.
  • Better understand insulation-related practical problems of operating utility companies for economical countermeasures.
  • Identify operating problems of the power sector which could be jointly researched through an effective academia-industry linkage program.

Who should attend?

  • Electrical engineers and senior technical staff of power utility companies (DISCOs) involved in design, erection, operation and maintenance of 132 kV (transmission lines) and 11 kV (distribution lines) including technical staff of allied grid stations under administrative control of DISCOs.
  • Electrical Engineers and senior technical staff of National Transmission and Dispatch Company (NTDC) involved in design, erection, operation and maintenance of its transmission network of 500 kV and 220 kV lines.
  • Electrical engineers and senior technical staff of K-Electric, Karachi involved in design, erection, operation and maintenance of transmission and distribution systems of K-Electric.
  • Consulting engineers of DISCOs and NTDC and their technical staff.
  • Planners of future HVDC transmission system in Pakistan.
  • Engineers and senior technical staff of high voltage laboratories operating in Pakistan.
  • Engineers and technical staff of manufacturers of electrical power equipment such as power transformers, distribution transformers, HV cables, HV insulators, circuit-breakers and other distribution and transmission class equipment in Pakistan.
  • Technical staff of Ministry of Water and Power and Ministry of Industries.

PROGRAM OUTLINE

Day 0
7:00 PM Arrival
8:00-9:30 PM Dinner
Day 1
8:30-10:00 AM BREAKFAST
10:00-12:30 AM General Aspects
  • IEC-based voltage classification
  • Choosing operating voltage for transmission lines –
  • World trend towards high voltage power transmission
  • Comparison of long-distance high power HVAC & HVDC transmission systems.
  • Role of Electrical insulation towards reliable operation of power system
  • Representative properties of insulating materials
1:00-2:00 PM LUNCH AND PRAYER BREAK
2:00-4:30 PM Gaseous Insulation System
  • Generation of charged particles & de-ionization processes
  • Townsend theory of breakdown
  • Uniform field breakdown
  • streamer theory
  • Non-uniform field breakdown
  • Choice of insulating gases for practical applications.

Liquid Dielectrics
  • Desirable properties
  • Commonly used insulating dielectrics
  • Mechanisms of breakdown of insulating liquids
5:00-5:30 PM TEA
8:00-9:30 PM DINNER
Day 2
8:30-10:00 AM BREAKFAST
10:00-12:30 PM Solid Insulation System
  • Major desirable properties of solid dielectrics
  • Solid insulating materials
  • Failure of solid dielectrics
    1. Puncture or internal failure
    2. Mechanism of internal failure
    3. External failure: flashover process
1:00-2:00 PM LUNCH AND PRAYER BREAK
2:15-4:30 PM Potential Overvoltages
  • Lightening: phenomena & associated overvoltages
  • Power system switching overvoltages
  • Power frequency overvoltages

Insulation Coordination
  • Line insulation coordination
  • Station insulation coordination
  • Statistical insulation coordination method
  • Conventional insulation coordination method
5:00-5:30 PM TEA
8:00-9:30 PM DINNER
Day 3
8:30-10:00 AM BREAKFAST
10:00-12:30 PM Insulation Quality Assurance: Equipment and Infrastructure
  • High voltage sources: AC, DC and impulse voltage.
  • Pollution test hall with fog-generation system
  • C and tanࢾ measuring system
  • Partial discharge measuring system
  • Environmental chamber
  • Gaseous insulation test chamber with voltage source and accessories.
1:00-2:00 PM LUNCH AND PRAYER BREAK
2:00-4:30 PM High Voltage Testing
  • Testing philosophy
  • Breakdown testing
  • Dielectric loss tests
  • Partial discharge test

Type Testing of Some Major Equipment
  • Distribution and power transformers
  • High voltage circuit breakers
  • HV cables - Surge arrestors
4:30-5:00 PM Closing Ceremony
05:00-05:30 PM TEA

Departure