Lecture Notes || SNS Courseware

Lecture Notes

UNIT 1:

Introduction to Protection Schemes

Principles and need for protective schemes

Nature and causes of faults

Type of faults

Fault current calculation using symmetrical component

Methods of neutral grounding

Zone of Protection scheme

Essential qualities of protection

Protective scheme

UNIT 2:

Principle and operation of protective

Universal relay

Torque equation

R-X diagram

Electromagnetic relays

Over current relay

Distance and differential relay

Negative and frequency relay

UNIT 3:

Introduction about apparatus protection

Current Transformer

Potential transformer

Protection of transformer

Protection of Generator

Protection of bus bar

Protection of motor

UNIT 4:

Introduction about protective relay

Static Relays

Phase and Amplitude comparator

Synthesis of various relay using static comparators

Block diagram of numerical relays

Over current Protection

Transformer differential protection

Distance protection of transmission lines

UNIT 5:

Re-striking voltage and recovery voltage

Rate of rise of recovery voltage

Comparison of different circuit breakers

Current chopping - interruption of capacitive current