About This Course

This seminar is specifically designed to provide a comprehensive understanding of power system protection design principles. Via a progressive “building block” approach, this seminar proceeds from the basic concepts, such as security, reliability, and duplication of power system protection through to a comprehensive consideration of the transmission system and power station plant protection. Thus, this seminar is specifically designed to meet the learning requirements of those who presently have only a fundamental knowledge of protection principles, while, via a progressive approach, also considering more advanced topics to thus provide valuable insight for those more experienced in the discipline of power system protection design. Hence, this seminar will assist both those whose day to day work involves them in the application of protection design, coordination, and relay setting and also those in less directly associated areas of electricity system design.

Know About Your Trainer

With 39 year’s experience in the Queensland electricity supply industry, our principal engineer, the seminar author and presenter, was involved in the design, coordination and implementation of protection schemes associated with Queensland’s HV and EHV transmission systems since 1981.

He has 25 year’s experience within Australia and internationally in the provision of university post graduate training on the design and implementation of HV and EHV Transmission Protection Systems and Power Station Generator Protection Systems. He has presented a number of papers on various specialized aspects of protection design at conferences both within Australia and internationally.

Who Should Attend This Training

This seminar has been prepared specifically to meet the requirements of:
  • Protection Design Engineers, to identify protection implications and to ensure design, coordination and relay setting principles provide the necessary levels of speed, security, dependability and safety.
  • Planning Engineers, to identify the difficulties in providing protection for various power system configurations under review
  • Maintenance Engineers, to ensure that system protection is not compromised as primary and/or secondary system plant is removed from service during maintenance
  • Circuitry Design Engineers, to ensure that protective schemes are implemented in a manner to provide optimum performance
  • Commissioning and Project Management Engineers, to ensure the actual field installation of the protection scheme and associated relay settings meets the design requirements
  • Technicians, to understand the importance of their role in installing, testing and maintaining effective, reliable, dependable and secure protection systems

What You Will Learn


Fundamental Principles of Power System Protection
  • Dependability and Security
  • Speed of Protection
  • Protection Zones & Overlap
  • The “ART” of Protection
    • Unit Protection Principles
    • Non-Unit Protection Principles
  • Redundancy and Duplication of protection
    • Duplicate Main Protection
    • Main and Local Back-up Protection
    • Main and Remote Back-up Protection
  • CB Fail Protection and Blind Spot Protection
Fault Studies and Sequence Components
  • Introduction to Fault Analysis
  • Per Unit Methodology
  • Classical Fault Study
  • Sequence Components
    • Phase – Phase Faults
    • Single Phase Faults
    • Resistive Earth Faults
    • Transformers and Sequence Networks
  • Three Phase faults
Voltage Transformers to IEC 60044
  • Voltage Transformer Specification
    • Magnetic VTs
    • Capacitor VTs
    • VT Transient Performance


Current Transformers to IEC 60044
  • P Class Current Transformer Specification
  • PX Class Current Transformer Specification
  • Transient Performance of CTs
    • Fault Currents and DC Offset
    • DC Offset, CT Flux and (1 + X/R)
    • Principles
Introduction to Distance Protection
  • Distance Zones, Time and Reach
  • Coordination
  • Primary and Secondary Impedances
  • Simple Amplitude Comparators
  • Impedance Circles
  • Simple Angle Comparators
  • Mho Circles
  • Polarizing for Close-In Faults
  • Zones of Protection – Circles and
  • Quadrilaterals
  • Three Phase Load Limit Performance
  • Comparator Configurations for :
    • 3 Phase and Phase-Phase Faults
    • Earth Faults with Ko compensation
Distance Relay Protection Signalling
  • Permissive Under Reach Transfer Tripping
  • (PUTT)
  • Permissive Over Reach Transfer Tripping
  • (POTT)
  • Blocking Intertripping
  • DEF Intertripping
  • PLC systems


Advanced Applications of Distance Protection
  • Mutual Coupling
  • Teed Feeders
    • DIT, PUTT, POTT and Blocking
    • Applications
  • Zone 3 Back-up Considerations
  • Fault Resistance
  • VT Supervision
  • Polarizing for Close-in Faults and SOTF
  • Logic
  • Power Swing Blocking
Feeder Digital Current Differential Protection
  • Data Synchronisation
  • Conventional Biased Differential Systems
  • Alpha Plane Systems
  • 2, 3 and Multi Ended Systems
  • Intertripping Schemes
  • Back-Up Distance Relay Functionality
High Impedance Differential Protection (Busbars)
  • HZ Differential Protection Principles
  • Setting Principles
    • Setting Voltage for Through Fault
    • Stability
    • CT Requirements for In-Zone Fault
    • Detection
  • Current Operated Relays with Stabilising
  • Resistors
  • Limiting HZ Protection Scheme Secondary
  • System Voltages Safely
  • Primary Operating Current
    • Application of Shunt Resistors
  • Bus Zone Protection Check Systems
  • CT Supervision Requirements
  • High Impedance Differential Protection
  • Schemes for
    other Galvanically (Electrically) Connected


Transformer Protection
  • Buchholz and Pressure Relief Devices
  • Bias Differential Basic Principles
  • Stability under Magnetising Inrush
  • Conditions
  • Stability under Over Excitation Conditions
  • Stability with Transformer Phase Shifts
  • Stability under through Earth Fault
  • Conditions
  • Determination of Delta CT Connection
  • Delta / Star Transformer Example
  • Determination of CT Ratios
  • Winding Neutral End Faults
    • Restricted Earth Fault Protection
  • Zig-Zag Earthing Transformers
  • Neutral Displacement Protection
Low Impedance Busbar Differential Protection
  • Central and Bay Unit Designs
  • Features to Accommodate Poor Quality CTs
  • Multiple Zone Applications
  • Allowance for Dynamic Switching of Plant
  • Voltage and Check Zone Interlocking
  • CB Fail and CB Fail Bus Trip Facilities
  • Blind Spot Fault Facilities
  • Multi Functionality
Induction Motor Protection
  • Thermal Capability and Starting Current, Stalling Current, High Inertia Loads and Number of Starts Limitation
  • Effects of Unbalanced (Negative Phase
  • Sequence – NPS) Events
  • RTD Protection
  • Star / Delta Starting Systems
  • Loss of Load Protection
  • Undervoltage Protection
  • Over Current and Earth Fault Protection

DAY FIVE (Half Day)

Synchronous Generator Protection Generator Faults
  • Generator Differential Protection Schemes
  • Voltage Displacement Protection
  • Stator Earth Fault Protection
  • (100%, 95% and 3rd harmonic schemes)
  • Rotor Earth Fault Protection
Generator Events
  • Stator Overload Protection
  • Negative Phase Sequence (NPS) Protection
  • Over Voltage and Over Excitation Protection
  • Under Excitation Protection
  • Reverse Power Protection
  • Under and Over Frequency Protection
  • Out of Step Protection