3 CLO1 Three Phase System
Page 1
International Islamic University Malaysia
Dr. Rijalul Flkri
Topic: Three Phase System
Page 2
Contents Overview:
AC-to-DC Conversion
Single Phase Alternator
Three Phase Alternator
Power Generation, Transmission, and Distribution
Page 3
Advantages of AC Over DC Systems:
Lower generating costs:
Simplicity of AC alternator construction
Higher rotation speed and lower maintenance costs
Easier voltage transformations:
Transformers can change AC voltage easily, allowing for efficient long-distance transmission.
Page 4
Power Transmission Overview:
Generating Station: Converts energy to electricity (69,000-765,000 Volts)
Transmission Substation: Steps down voltage (11,000 to 25,000 Volts)
Subtransmission: Steps down voltage further (22,000-69,000 Volts)
Distribution Substation: Final voltage adjustments for residential and commercial loads.
Page 6
AC-to-DC Conversion Needs:
Electronic equipment requires DC (e.g., computers, TV, industrial processes).
AC is converted to DC using rectifiers; DC can be converted back to AC with inverters.
Page 7
Single Phase Electric Power:
Distribution system with alternating current.
Primarily used for lighting and small motors; larger motors necessitate additional circuits for starting.
Page 8-9
Single Phase Alternator:
AC voltages induced in the armature coil as the field rotates.
Generators convert mechanical energy into electrical energy (e.g., moving wires in a magnetic field).
Page 12-13
Three Phase Alternator:
Comprised of three single-phase coils phase-displaced by 120 degrees.
Outputs are staggered, resulting in continuous power generation.
Page 14-15
Connection Configurations:
Star (Wye) and Delta configurations in three-phase systems.
Each phase can be connected to form a neutral point.
Page 18
Frequency and Voltage:
Frequency is determined by pole count and speed of field rotation; voltage can be adjusted by changing magnetic field strength.
Page 23
Electric Machines:
Motors convert electrical energy to mechanical energy.
Generators convert mechanical energy to electrical energy.
Page 31-32
National Grid and Power Distribution:
High voltage (up to 400 kV) transmission minimizes energy loss.
Step-up and step-down transformers adjust voltages for user applications.
Page 34
Electrical Distribution Systems:
Categorized into transmission systems (115kV to 800kV) and distribution systems (120V to 69kV).
Page 41-43
Principal Components of Electrical Installation:
Service conductors, service equipment, metering equipment, panel boards, switchboards, and wiring circuits.
Page 45-47
Types of Electric Cables:
Includes coaxial, flexible, shielded, and fiber internet cables, each serving specific functions in electrical applications.
Page 48
Fiber Internet vs. Cable Internet:
Fiber offers faster speeds with symmetrical upload/download, while cable provides variable performance but more availability.
Page 49
Thank you!