This online course has been designed to give plant operators, electricians, field technicians and engineers a better appreciation of the role played by power system protection systems. An understanding of power systems along with correct management will increase your plant efficiency and performance as well as increasing safety for all concerned.

The course is designed to provide excellent understanding on both a theoretical and practical level. Starting at a basic level and then moving onto more detailed applications, it features an introduction covering the need for protection, fault types and their effects, simple calculations of short circuit currents and system earthing. This course includes some practical discussion on simple fault calculations, relay settings and the checking of a current transformer magnetisation curve.

 

YOU WILL LEARN HOW TO

• Describe the fundamentals of electrical power protection
• Identify and understand the different fault types
• Perform simple fault and design calculations
• Basically  specify and use protection system components – CTs, VTs, CBs, fuses and relays
• Apply relay settings; check, test and assess current transformers
• Demonstrate a fundamental knowledge of different applications in protection

 

WHO SHOULD COMPLETE THIS COURSE

• Design engineers
• Electrical engineers
• Electrical technicians
• Electricians
• Field technicians
• Instrumentation and design engineers
• Plant operators
• Project engineers

 

COURSE OUTLINE
RELAYS

• Inverse, Definite Minimum Time (IDMT) relay – construction principles and setting
• Calculation of settings – practical examples
• New era – modern numerical relays and future trends

 

FEEDER PROTECTION

• Cables
• Pilot wire differential
• Overhead lines
• Distance protection (basic principles, characteristics, various schemes)

 

TRANSFORMER PROTECTION

• Phase shift, magnetising in-rush, inter-turn, core and tank faults
• Differential and restricted earth fault schemes
• Buchholz relay, oil and winding temperature
• Oil – testing and gas analysis

 

SWITCHGEAR (BUSBAR) PROTECTION

• Requirements, zones, types
• Frame leakage, high, medium and low impedance schemes, reverse blocking

 

NEED FOR PROTECTION

• Selectivity, stability, sensitivity, speed
• Reliability, dependability, security

 

FAULT TYPES AND THEIR EFFECTS

• Active, incipient, passive, transient, asymmetrical etc
• Phase and earth faults

 

SIMPLE CALCULATION OF SHORT CIRCUIT CURRENTS

• Revision of simple formulae
• Calculation of short circuit MVA and fault currents
• Worked examples

 

SYSTEM EARTHING

• Solid, impedance, touch potentials etc
• Effect of electric shock on human beings
• Earth leakage protection

 

PROTECTION SYSTEM COMPONENTS INCLUDING FUSES

• History, construction, characteristics
• Energy, let-through, application

 

INSTRUMENT TRANSFORMERS

• Current transformers: construction, performance, specification, magnetisation, curves etc
• Voltage transformers: types, accuracy, connections

 

CIRCUIT BREAKERS

• Purpose and duty, clearance times, types etc

 

TRIPPING BATTERIES

• Battery types, chargers, maintenance, D.C. circuitry

 

PRACTICAL DEMONSTRATION SESSION

• Including simple fault calculations, relay settings and checking a current transformer, magnetising curve etc.

 

APPLICATIONS CO-ORDINATED BY TIME GRADING

• Problems in applying IDMT relays

 

UNDERGROUND MINE DISTRIBUTION PROTECTION

• Earth leakage protection, pilot wire monitor, earth fault lockout, neutral earth resistor monitor
• Selective co-ordination by current grading

 

PRINCIPLES OF UNIT PROTECTION

• Differential protection – basic principles

 

MOTOR PROTECTION

• Thermal overload, time constants, early relays
• Starting and stalling conditions
• Unbalanced supply voltages, negative sequence currents, de-rating factors
• Phase-phase faults
• Earth faults – core balance, residual stabilising resistors

 

GENERATOR PROTECTION

• Stator and rotor faults
• Overload and over-voltage
• Reverse power/unbalanced loading
• Loss of excitation and synchronism
• Typical protection scheme for industrial generators

 

MANAGEMENT OF PROTECTION

• Routine testing, annual testing, investigation and performance assessment, up-grading
• Organisation, training, records, access planning