Basic Electrical Engineering
Prof. Ramya Selvaraj
Dept. of Electrical Engineering
Introduction
Course objectives
• To impart the basic knowledge of the Electric and Magnetic circuits.
• To understand the basic concepts of single phase and three phase AC
circuits.
• To impart basic knowledge of various electrical machines and
measuring instruments.
Why electricity? Why is it popular?
• Progress of a nation depends on the per capita consumption of
electrical energy
• India – 300; UK-12-15 times more; USA- 30 times more
• Main reasons for its popularity
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Cleaner environment
Higher efficiency
Better controllability
Long distance transportation
Easier to convert electrical energy into other versions like thermal,
illumination, sound, mechanical etc
Sources for Generation of electricity
• Conventional methods
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Thermal
Hydro-electric (Hydel)
Nuclear
• Non-conventional methods
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Wind
Solar
Biomass
Waste to energy
The break up of renewable energy sources (RES) is:
•Solar power (36,910.53 MW)
•Wind power (38,433.55 MW)
•Biomass (10,145.92 MW)
•Small hydro (4,740.47 MW)
•Waste-to-energy (168.64 MW)
Comparison of sources of electricity
generation
• Initial cost
• Running costs
• Limitations
• Perpetuity-efficiency-reliability-cleanliness-simplicity
Transmission and Distribution of Power
Why do we need insulators?
What is the typical no of phases and frequency
used for generation of electric power?
Contd..
• Why are we transmitting the power at a higher voltage as
compared to the generating voltage?
Typical voltage levels in a power system
Lesson 1: Overview
Generation, Transmission and Distribution of
Electric Power
Goals
• Different methods of generating electrical power.
• Issues involved in transporting this power to different types of consumers located
generally at far off places from the generating stations
• Necessity of substations to cater power to consumers at various voltage levels.
A.C. Generator
3Φ 50 Hz supply
Thermal
Basic components of a thermal power plant
Merits
• Fuel (=coal) is cheap
• Less initial cost is required
• Less space
• Therefore the cost of generation for 1
unit of electrical energy is cheaper
Disadvantages
• Atmospheric pollution is quite high
• Transportation cost might become high
in the future
Hydro-electric
Basic components of a Hydel power plant
Merits
• Renewable
• Emission free
• Reliable
• Adjustable
• Create lakes
• Faster developed lands
Disadvantages
• Impact on fish
• Limited Plant locations
• Higher initial costs
• Susceptible to droughts
• Flood risks
Nuclear
Basic components of a nuclear power plant
Merits
• Quantity of fuel required for one unit of
electricity gen. is less
• Cheaper running costs
• More reliable
• Efficient when running at the rated
capacity
Disadvantages
• Fuel is expensive and not available in
abundance
• High capital costs
• Maintenance is high
• Nuclear waste disposal is a problem