Electrical High voltage surge protection

A surge arrester is a device to protect electrical equipment from overvoltage transients caused by external, lightning overvoltage, or internal, switching overvoltage events. This training class of device is used to protect equipment in electrical power systems.

Surge Arresters are the primary protection against atmospheric and switching overvoltage. They are generally connected in parallel with the equipment to be protected to divert the surge current. This training course is an overview of the high voltage surge arresters application, including functioning, construction, selection, installation location , and a short overview of the last generation of surge arresters before the introduction of the metal-oxide arrester, that is, the gapped silicon-carbide arrester, which is still being extensively used today.

This training course will provide information on how to reduce the risk of insulation failure of key electrical equipment, minimize outages, improve system reliability and reduce costs. The presentation covers both conventional valve-type surge arresters as well as the metal oxide devices.

By the end of the course the participants will be able to:

  • Understand the difference between direct and indirect lightning
  • Understand the origins of surges on
  • Able to determine the location of surge diverters; ability to size and specify a surge arrester; understand the concept of insulation co-ordination and able to determine how the surge diverter impacts the insulation coordination of the entire electrical network.

Duration: 3 days

Agenda:

DayContent/Topics
1

Pretest.

  • ·        Power system main configuration and component
  • ·        Electrical hazards and safety points
  • ·        Standard values of voltage levels
  • o    IEC
  • o    IEEE
  • ·        What is lightning
  • ·        Reasons of lightening
  • ·        An electric discharge
  • ·        Types of lightning
  • o    Ball lightning
  • o    Fork lightning.
  • ·        Effects of lightning
  • ·        Standardization of lightning and surge protection
  • o    IEC 62305 – Designing for Protection Against Lightning
  • o    IEC 62305-1: General Principles
  • o    IEC 62305-2: Risk management
  • o    IEC 62305-3: Physical damage to structures and life hazard
  • o    IEC 62305-4: Electrical and electronic systems within structures
  • o    IEC 62561 – Lightning Protection System Components (LPSC)
  • o    IEC 62305 – Protection Against Lightning
  • ·        New development in lightning protection.
  • o    General
  • o    Down-conductor
  • o    Air termination
  • ·        Group Discussion & Quiz
2
  • ·        Meaning and importance of Earthing / Grounding
  • ·        Electrical system without Earthing / Grounding system
  • ·        Basics of grounding/earthing & Bonding.
  • ·        Different types of functional & Protective Earthing / Grounding.
  • ·        Protective measurement according to IEC 62305
  • ·        Electricity shock & hazards & Equipment Earthing / Grounding
  • ·        Static charges and the need for bonding.
  • ·        System Earthing, Fault Current and Earth Terminals in Electrical Networks
  • ·        Earthing Standards
  • ·        Earthing types as per BS 7671 & IEC 60364.
  • o    IT Unearthed or High impedance earthed neutral.
  • o    TT Solidly earthed neutral.
  • o    TNC Combined Neutral earthing.
  • o    TNS Separate Neutral earthing.
  • o    TNCS Separate & combined Neutral earthing.
  • ·        Lightning Protection Test (LPT)
  • ·        Earthing through
  • o    Resistance earthed.
  • o    Reactance earthed systems.
  • o    Effectively & in-effectively earthed systems
  • §  Effect on fault induced system surges
  • ·       Group discussion & Quiz
  • 3

Facts about lightning

  • ·        Fault induced surges.
  • ·        Transient over voltages and mitigation
  • ·        Static electricity and protection
  • ·        Lightning arrestor
  • ·        Lightning arrestor idea of operation
  • ·        Lightening arrestor metal oxide varistor (MOV)
  • ·        Typical lightening arrestor
  • ·        Transformer lightning arrestor
  • ·        Home lightning arrestor
  • ·        Electrical tower lightning arrestor
  • ·        Different types of lightning protection

 

  • o    Rods
  • o    Meshed
  • o    Early streamer emission (ESE)
  • o    Catenary wire
  • o    Using natural component
  • ·        Person – lightning safety position (LSP)
  • ·        Testing of lightning protection systems
  • o    Inspect lightning rods and other equipment for damage.
  • o    Check for loose connections.
  • o    Monitor new roof installations and equipment.
  • o    Down-conductors have a continuous path.
  • o    New development
  • ·        Lightning protection checklist
  • ·        General discussion
  • ·        Post test