Course Details

Objective

This course introduces the basis of understanding the theory of high voltage switchgear covering LV/MV/HV circuit breakers and the equipment included in the switch gears. It also introduces the practice and testing of switchgear & by the end of this course the trainee should be able to:

• Demonstrate the components of different voltage switchgear.
• Demonstrate the maintenance and testing procedures used for different voltage switchgear.
• Apply the safety precautions of P.M. on switchgear.
• Know how to calculate the short circuit level.
• The transient phenomena in power systems
• Understand the arc phenomena and circuit interruption.
• Know the different types of circuit breakers and industrial switchgear.
• Be able to select the proper specifications of CB and switchgear.
• Know the maintenance procedures.
• Be able to do all tests on circuit breakers.
• Be able to detect circuit breakers troubleshooting.
• Know the methods of system earthing and protection requirements.
  Be able to control circuit breakers with associated relaying systems.

Content

1. WORKSHOP KEY TOPICS

2. Basic Concepts of Power Systems (Generation, Transmission, and Distribution of Power)
3. Short Circuit Basics of Electrical Network Systems
4. Breaking of AC
5. Introduction to Switchgears
6. High voltage switchgear
7. Low & medium voltage switchgear
8. Testing, Troubleshooting Principles and Commissioning Guide of Electrical Equipment
9. Condition Monitoring for Electrical Equipment
10. Switchgear testing.
11. Typical example of Maintenance of M.V SF6 breaker and switchgear assembly.
12. Typical example of Maintenance of M.V vacuum breaker and switchgear assembly
13. Functions of Circuit Breakers
14. Circuit Breaker Components
15. Design Features of Circuit Breakers
16. Application of Circuit Breakers (Generators, Motors & Transformers Protection)
17. Description of some reputed make Circuit Breakers
18. Installation and Commissioning of Circuit Breakers
19. Testing of Circuit Breakers
20. Analysis of Circuit Breakers Performance
21. General Maintenance of Circuit Breakers
22. Application of CBM on Circuit Breakers
23. Modern Trends     

1. Introduction 
   •    Electrical engineering basic concepts
   •    Three-phase review and per unit 
   •    Voltage levels
   •    One-line and three-line diagram
   •    Generation system layout
   •    Transmission system layout
   •    Substation system layout
   •    Distribution system layout
2. Industrial Switchgear
   •    Fuses
   •    Auto-reclosers
   •    Automatic sectionalized
   •    Circuit Breakers
   •    Isolator switches
   •    Load switches
   •    Relays
   •    Current transformers
   •    Voltage transformers
    
3.  CB Design Specification Based on Short Circuit Current Level
   •    Per unit system
   •    Faults on power systems
   •    Transient phenomena in power systems.
   •    Symmetrical component analysis of a phase network
   •    Network connection for various fault types
   •    Current and voltage distribution in the system due to a fault
   •    Effect of the system on zero sequence quantities
   •    Computer programs based on short circuit calculation.
4. CB Design Specification Based on Arc Phenomena and Circuit Interruption
   •    Arc phenomena
   •    Maintenance of the Arc
   •    Properties of Arc
   •    Arc Interruption theory
   •    Circuit Breaker Rating
   •    Circuit constants and circuit conditions
   •    Conditions of severity
   •    Restriking voltage transient
   •    Switching transients
   •    Duties of Switchgear
5. Testing, Troubleshooting Principles and Commissioning Guide of Electrical Equipment

• Introduction
• Basic principles in using a drawing and meter in Troubleshooting circuits.
• Checks for circuit continuity with disconnected supply.
• Checks for circuit continuity with live supply.
• Tests and methods
• Testing devices
• Testing and Commissioning Methods
• Testing and Commissioning Procedures.
• Maintenance of Particular Types of Electrical Equipment
• Nomo gram for temperature correction
• Test voltages for Commissioning and Maintenance
• Recommended insulation values for equipment

6. Condition Monitoring for Electrical Equipment

• Approaches Based on Mathematical Models
  • Reliability Centered Maintenance (RCM)
  • Condition Based Maintenance (CBM)
  • Partial Discharge
• Insulation Resistance Monitoring
  • Insulation resistance test (IR)
  • Megger test
  • Polarization index test
  • Dc hi-pot test
  • Measuring insulation degradation
  • Insulation power factor
  • Online measuring partial discharge activity for insulation
• On-Line Monitoring of Transformers
  • Local Indications
  • Thermography
  • PDA - Partial Discharge Analysis
  • Insulating Oil Properties and Tests
    • Test for Dielectric Strength
    • Water Content in Oil
    • Acidity Test (Neutralization Number)
    • Oxidation Inhibitor
    • Interfacial Tension Test (IFT)
    • Oil Colour
    • Oil Power Factor Test
    • Insulating Oil Dissolved Gas Analysis (DGA)
• Understanding cable thermal behavior after installation
• Optical cable Temperature Monitoring

7. LV Circuit Breakers
   •    Low voltage molded case current limiting circuit breakers
   •    Low voltage molded case circuit breakers with high breaking capacity
   •    Insulated case circuit breakers
   •    Low voltage air circuit breakers
   •    Low voltage circuit breaker specification
8. Modern MV and HV Vacuum CB
   •    Introduction
   •    Advantages of vacuum interruption
   •    Vacuum contactors and interrupters
   •    The vacuum medium
   •    The vacuum arc
   •    Vacuum arc stability
   •    Vacuum breakdown
   •    Vacuum switch construction
   •    Applications of vacuum circuit breakers
9. Modern MV and HV SF6 CB Introduction
   •    Basic Features of SF6 Breakers
   •    Dielectric properties of SF6
   •    Quenching properties of SF6
   •    Construction of SF6 breaker
   •    SF6 CB types
   •    Puffer type SF6 breakers
   •    Double Pressure System
   •    Single Pressure Puffer-Piston System
   •    Single Pressure Self Blast System
   •    Improvement in SF6 Breakers for HV
10. Other Types of Circuit Breakers
    a) Air Circuit Breakers
    •    Method of increasing arc resistance
    •    Plan break type
    •    Magnetic blowout type
    •    Arc splitter type
    •    Application
    •    Construction and operation
    •    Axial air CB
    •    Blast air CB

b) Oil Circuit Breakers
•    Arc rupture under oil
•    Advantages of oil
•    Disadvantages of oil
•    Plan break oil circuit breakers
•    Arc control circuit oil breakers
•    Minimum oil circuit breakers
•    Construction and operation

11. Circuit Breaker Inspection, Maintenance, and Services
    •    Inspection
    •    General inspection technical procedure
    •     Daily inspection of circuit breakers
    •     Monthly inspection of circuit breakers
    •     Annual inspection of circuit breakers
    •    Disassembly 
    •    Cleaning 
    •    Tightening 
    •    Lubrication 
    •    Equipment used in testing
    •    Testing procedure
    •    Direct testing
    •    Contact resistance test.
    •    Insulation resistance test
    •    Test report
    •    Indirect testing
    •    One hour Video, HV CB Maintenance and Repair)
12. Circuit Breakers Control, Protection and Testing
    •    Switchgear control devices and wiring 
    •    Switchgear protection devices and wiring
    •    Testing Classification
    •    Testing laboratories
    •    Description of a simple testing station.
13. CB Troubleshooting
    •    Low insulation Resistance (below 2000 Mega-ohms) between a) Phase terminal and earthed frame, with breaker closed b) Phase terminals of a pole.
    •    Resistance between Terminals of Pole contact.
    •    Unequal contact Wipe and Travel in 3-pole Measured from the top surface of the interrupter flange and the contact lip by a simple rod with a) breaker open and b) breaker closed
    •    One of the poles does not close.
    •    Breaker operation too Slow During opening timing from trip command to contact separation instant too large

Case Studies, Last Day Review, Discussions, and assessments will be carried out.

TRAINING OUTCOME

By the end of this course the participants will gain the following;
•    Know how to calculate the short circuit level.
•    The transient phenomena in power systems.
•    Understand the arc phenomena and circuit interruption.
•    Know the different types of circuit breakers and industrial switchgear.
•    Be able to select the proper specifications of CB and switchgear.
•    Know the maintenance procedures.
•    Be able to do all tests on circuit breakers.
•    Be able to detect circuit breakers troubleshooting.

•    Know the methods of system earthing and protection requirements.
•    Be able to control circuit breakers with associated relaying systems.

NOTE:

Pre & Post Tests will be conducted.

Case Studies, Group Exercises, Group Discussions, Last Day Reviews and assessments will

be carried out.

………………………………….

Methodology

A highly interactive combination of lectures and discussion sessions will be managed to maximize the amount and quality of information and knowledge transfer. The sessions will start by raising the most relevant questions and motivating everybody to find the right answers. You will also be encouraged to raise your questions and to share in the development of the right answers using your analysis and experiences.  Tests of the multiple-choice type will be made available daily to examine the effectiveness of delivering the course.

Very useful Course Materials will be given.

• 30% Lectures
• 30% Workshops and work presentation
• 20% Group Work& Practical Exercises
• 20% Videos& General Discussions