Power System Protection Library

Power System Protection Library

     Application of differential protection
     Principle of circulating current differential (MERZ-PRIZE) protection
     Difficulties of differential protection
     Differential protection of 3-phase circuit
     Biased or per cent differential relay
     Setting of differential relay
     Balanced voltage differential protection

Distance Protection
     Introduction to Distance Protection
     Principle of R-X Diagram
     Theory of Impedance Measurement
     Methods of Analysis
     Directional Impedance Relay
     Torque Equation of Directional Impedance Relay
     Modified (Shifted) Characteristic
     Reactance Type Distance Relay
     Mho Type Distance Relay
     Application of Distance Protection

Overcurrent Protection and Earth Fault Protection
     Application of Over-current protection
     Relays used in over-current protection
     Characteristics for relay units for over-current protection.
     Earth fault protection
     Connection of CT's for earth fault protection
     Combined earth fault and phase fault protection
     Earth fault protection with core balance current transformer (Zero sequence ct)
     Frame leakage protection
     Directional over-current protection
     Directional earth fault protection

Protection of Transmission Line
     Non directional time graded system of feeder (or line ) protection.
     Directional time and current graded system
     Setting of directional over-current relays of ring main
     Current Graded Systems
     Definite time over-current protection of lines
     Earth fault protection of line
     Summary of Over-current Protection of Lines
     Introduction to Distance Protection of H.V. and E.H.V. Lines
     Distance Schemes
     Starting Element (Fault detector)
     Stepped Characteristic
     Three Step Distance-Time Characteristic
     Power swing
     Carrier Assisted Distance Protection.
     Distance Scheme for Single Pole and Triple-pole Auto-reclosing
     Connection of Distance Relays
Protection of Transmission Line (Part3) - Part c : Protection of Lines Based on Unit Principle
     Pilot Protection Using Circulating Current Differential Relaying
Protection of Transmission Line (Part4) - Part D: Carrier Current Protection of Transmission lines
     Carrier Current Protection
     Phase Comparison Carrier Current Protection
     Applications of Carrier Current Relaying
     Radio Links or Microwave Links

Transformer Protection
Transformer Protection
     Possible Transformer Faults
Winding Temperature Protection

Generator Protection
generator Protection
     General Faults
Examples on Generator Protection

Induction Motor Protection
Induction Motor Protection
     Various Faults and Abnormal Operating Conditions
     Starting Current
Busbar Protection
     Busbar Faults
Nondirectional Time and Current Graded Method Protection
     Use of Inverse Time Relay
     Setting of Inverse Overcurrent Relays
     Disadvantage of nondirectional Time and Current Graded Method
Directional Time and Current Graded Protection
     Parallel Feeder Protection
      Tee Feeder Protection
     Ring Main and interconnected System
Differential Protection of Feeders (Pilote Wire Protection)
     Merz-Price Voltage Balance System
     Translay Scheme


  1. Don't find fault, find a remedy. See the link below for more info.



  2. Good day! I read your article and learn about it. Thanks for sharing your expertise and information about this study. I also have a site imarksweb.net ,kindly open if you have time :) Thanks. GBY

  3. The essential elements of protection is a sensor to identify the faulty condition and a device to initiate tripping signal to the Circuit breaker.
    Power transformers in India | Transformer manufacturer in India