t
iap0 = sub − max imum
t
•
Em
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta
i[0] ip0
iap 0
ϕ' α
•
ϕ Im
•
•
I m − I pm
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2
t
Short-circuit
of
ConstanE•t
Voltage
m
Source
Circuit
ϕ' α
i[0]
•
Im
t
•
Em
e = Em sin(ωt + α ) i = I pm sin(ωt + α −ϕ)
Im =
Em
(R)2 + ω 2L2
ϕ ' = arctg ωL
R
i[0] ip0
ϕ' α
iap0 = 0
t
t
•
Em
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta
i[0] ip0
iap 0
ϕ' α
•
ϕ Im
•
•
I m − I pm
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2 Short-circuit of Constant Voltage Source Circuit
Chapter 5 3-phase Short-circuit
Transient of Power Systems
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-1 The Overall Concept of Short-circuit
ϕ ' = arctg ωL
R
i[0] ip0
iap 0
•
Em
ϕ' α
•
ϕ Im
•
•
I m − I pm
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2 Short-circuit of Constant Voltage Source Circuit
5-2 Short-circtuit of Constant Voltage Source Circuit
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta
−t
= I pm sin(ωt + 0o − 90o ) + I pme Ta
5-2 Short-circtuit of Constant Voltage Source Circuit
iap0 = max imum
t
•
Em
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta
i[0] ip0
iap 0
ϕ' α
•
ϕ Im
•
•
I m − I pm
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
•
ϕ Im
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2 Short-circuit of Constant Voltage Source Circuit
t
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta

e = Em sin(ωt + α ) i = I pm sin(ωt + α −ϕ)
Im =
Em
(R)2 + ω 2L2
ϕ ' = arctg ωL
R
i[0] ip0
iap 0
•
Em
ϕ' α
•
ϕ Im
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2 Short-circuit of Constant Voltage Source Circuit
t
−t
i = I pm sin(ωt + α − ϕ) + iap0e Ta
e = Em sin(ωt + α ) i = I pm sin(ωt + α −ϕ)
Im =
Em
(R)2 + ω 2L2
Im =
Em
(R + R' )2 + ω 2 (L + L' )2
ϕ
'
=
arctg
ω(L + L' )
R + R'
t
•
Em
ϕ' α
i[0]
•
Im
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2
t
Short-circuit
of
ConstanE•t
Voltage
m
Source
Circuit
ϕ' α
i[0]
•
Im
t
•
Em
e = Em sin(ωt + α ) i = I pm sin(ωt + α −ϕ)
Im =
Em
(R)2 + ω 2L2
ϕ = arctg ωL
R
α
ip0
ϕ
•
I pm
Chapter 5 3-phase Short-circuit Transient of Power Systems
• The Cause of Short-circuit • The Type of Short-circuit • The Consequences of Short-circuit • The Purpose of Short-circuit Calculation
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-1 The Overall Concept of Short-circuit
Types of Short-circuit
Type
Schematic diagram
Symbol
3-phase short-circuit
f (3)
Double line-ground f (3) Line-line
Single line-ground
f (1,1)
f (2) f (1)
Chapter 5 3-phase Short-circuit Transient of Power Systems
5-2 Short-circuit of Constant Voltage Source Circuit
e = Em sin(ωt + α )
i = Im sin(ωt + α −ϕ ' )