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JJ102 Electrical Technology
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Prepared By:Sheilani Binti ShaariDepartment of Electrical Engineering/PKB
Course Learning Outcome (CLO)
Upon completion of this course, students should be able to:
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Apply the principles of three phase systems, balanced load, star and delta type of connection to solve electrical circuit correctly.
CONTENT
1.INTRODUCTION2.3 PHASE SYSTEM3.DIFFERENCE 3 PHASE & 1 PHASE
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3.DIFFERENCE 3 PHASE & 1 PHASE4.3 PHASE LOAD CONNECTION
5.3 PHASE POWER
LEARNING OUTCOMES
General Objective (GO)Student should be able to understand the basic principles of a three phase system.
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principles of a three phase system.
Specific Objectives(SO)Student should be able to:1.Define three phase system with diagram. 2.Differentiate between three phase system and single phase system
3.State three phase supply consists of three phase conductors.
Generation System Transmission System Distribution System
INTRODUCTION
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11kv 132kv 415v
240v
Three phase Single phase
INTRODUCTION
3Phase System Is 3 separate coil
conductors which
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conductors which 120o apart
Produce 3 voltage source with same magnitude but different phase 120o.
Three-phase system have 3 phase conductor or live wire :
INTRODUCTION
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1. Red Phase, R2. Yellow Phase, Y3. Blue Phase, B
R
Y
B
0
120
240
3 SYSTEM
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R
YB emf is generated using 3 conductor
conductors have the
R
Y B
conductors have the same coils and rotating at a constant speed
3 SYSTEM
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the emf generated has the same three-emf amplitude or peak value with phase shift
R YB
peak value with phase shift of 120 and same frequency.
Dge
EER EY EB
0sinmE omE 120sin
3 SYSTEM
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EmER EY EB
0 120 240
Waveform of 3 System
o
mE 240sin
sinmR EE =)120sin( omY EE =
)240sin( omB EE = emf
3 SYSTEM
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)240sin(mB EE = Em
ER EY EB
0 120 240
Equations of 3 System
emf
EER EY EB om
omR
EE
EE
120
02
=
=
3 SYSTEM
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EmER EY EB
0 120 240
omB
omY
EE
EE
2402
1202
=
=
Equations of 3 System represent in a form of phase
3 SYSTEM 1 SYSTEMDefinition: Definition:
DIFFERENT 3 & 1 SYSTEM
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Definition:System with 3 live cabels from supply to load : Red phase(R), Yellow phase (Y) and Blue phase (B).
Definition:System with 2 cable connecting from source to load: Life cable (L) and neutral cable (N).
3 SYSTEM 1 SYSTEMConnection: Connection:
DIFFERENT 3 & 1 SYSTEM
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Connection: Connection:
240v
L
N
Load
R
Y
B
N
415v
240v
3 SYSTEM 1 SYSTEMWaveform: Waveform:
DIFFERENT 3 & 1 SYSTEM
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Waveform: Waveform:V
240
0
90
180
415
V
R Y B
0120 240
1. Transmission system
2. Supply power to
APPLICATIONS OF 3 SYSTEM
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2. Supply power to large factories
3. Starting the 3 machines.
More economical due to less construction and maintenance costs
ADVANTAGES OF 3 SYSTEM
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conductor used is smaller, thus the needs of copper can be reduced.
Easy to installed due to smaller and lighter cable used.
ADVANTAGES OF 3 SYSTEM
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Therefore the smaller structures supporters can be used and the distance between the supporters can be relatively long.
The characteristics of 3 equipment have a better operating starting due to its stable and fixed power.
ADVANTAGES OF 3 SYSTEM
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to its stable and fixed power.
Electrical energy supplied is higher than 1.
Most large motors used for induction motor 3 can stand alone without the additional equipment such as
ADVANTAGES OF 3 SYSTEM
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the additional equipment such as capacitors, centrifugal switches or other additional circuits
The output Production and equipment quality of work for 3 system is better than 1 because of
ADVANTAGES OF 3 SYSTEM
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system is better than 1 because of the higher efficiency and power factor .
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CONTENT
1.INTRODUCTION
2.3 PHASE SYSTEM
3.DIFFERENCE 3 PHASE & 1 PHASE
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3.DIFFERENCE 3 PHASE & 1 PHASE
4.3 PHASE LOAD CONNECTION5.3 PHASE POWER
LEARNING OUTCOMES
General Objective (GO)Student should be able to understand the basic principles of a three phase system.
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principles of a three phase system.
Specific Objectives(SO)Student should be able to:
1. State that three phase loads can be connected in delta or star.
2.State balanced star and delta connection.
3.Determine the power in three phase system.
CONTENTS
3PHASE LOAD CONNECTION STAR CONNECTION 3PHASE VOLTAGE AND CURRENT
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3PHASE VOLTAGE AND CURRENT
DELTA CONNECTION 3PHASE VOLTAGE AND CURRENT
3PHASE POWER APPARENT POWER, REAL POWER AND REACTIVE POWER
3 LOAD CONNECTION
Load on each phase is usually balanced.
The connections have 4 conductor
3 live wire and 1 neutral wire:
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3 live wire and 1 neutral wire:
Red Line, R
Yellow Line,Y
Blue Line, B
Neutral line, N
3 LOAD CONNECTION
There are 2 methods of load connection in 3 system
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DELTA ( ) STAR ( Y )
RLoad
STAR CONNECTION
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N
Y
B
Load
LoadLoad
Line Voltage (VL)
voltage that measure between 2 life
STAR CONNECTION
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voltage that measure between 2 life wire.
- ERY , EYB dan EBR
Phase Voltage (VP)
STAR CONNECTION
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Voltage that measure between life and neutral wire
- ERN , EYN dan EBN
VL = ERB VL = EYRVP = ERN
R
Load
STAR CONNECTION
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VL = EYR
VL = EBY
VP = EBN VP = EYN
N
Y
B
Load
LoadLoad
Voltage Formula
STAR CONNECTION
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Line Voltage = 3 Phase VoltageVL = 3 VP
Line Current (IL)
Current that flow in line
STAR CONNECTION
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Current that flow in line
- IR , IY and IB
Phase Current (IP)
STAR CONNECTION
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Current that flow in phase
- IPR , IPY and IPB
RLoad
IL = IR IP = IPR
STAR CONNECTION
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N
Y
B
Load
Load
Load
IL = IY
IL = IB
IP = IPB
IP = IPY
Current Formula
STAR CONNECTION
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Line Current = Phase CurrentIL = IP
Example
3 ballance load STAR connection have 10
STAR CONNECTION
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3 ballance load STAR connection have 10resistance and 0.019H inductance. The supplyvoltage is 415V, 50Hz. Calculate:i. Line voltage,ii. Phase voltage,iii. Line current andiv. Phase current
RDELTA CONNECTION
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B
Y
Load
Load
Load
VL
DELTA CONNECTION
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VL
VL
VPVL
Y
Load
Load
Load
Voltage Formula
DELTA CONNECTION
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Line Voltage = Phase VoltageVL = VP
IL = IRIP = IPR
DELTA CONNECTION
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Y
Load
Load
Load
IL = IYIP = IPY
IL = IB
IP = IPB
Current Formula
DELTA CONNECTION
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Line Current = 3 Phase CurrentIL = 3 IP
Example
3 ballance load DELTA connection have 10
DELTA CONNECTION
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3 ballance load DELTA connection have 10resistance and 0.019H inductance. The supplyvoltage is 415V, 50Hz. Calculate:i. Line voltage,ii. Phase voltage,iii. Line current andiv. Phase current
3 POWER
Power in 3 phase is the same as insingle phase
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3 types three phase power:1. Apparent Power,
2. Active / Real Power and
3. Reactive / Reactance Power
APPARENT POWER
Single Phase :
PPP IVS = VA
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3 Phase :
VA
PxSS 33 =PPIV3
LLIV3=
=
REAL POWER
Single Phase :WcosPPP IVP =
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3 Phase :
W=
PxPP 33 =cos3 PPIVcos3 LLIV=
REACTIVE POWER
Single Phase :VARsinPPP IVQ =
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3 Phase :
VAR=
PxQQ 33 =
sin3 LL IVsin3 PPIV=
SQ
sinPPP IVQ = PPP IVS =
POWER TRIANGLE
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S
P
Q
=3Q sin3 LLIV
=3P cos3 LLIVcosPPP IVP =
=3S LLIV3
Example
Calculate:
3 POWER
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Calculate:
i. Apparent power,
ii. Real power,
iii. Reactive power
for both connections in previous example.
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SOLVE PROBLEMS(Q1 Q13)
NEXT:CHAPTER 4
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BASIC PRINCIPLE OF ELECTROMAGNETIC