Siemens SINAMICS S120 - Page 123

Line Connection Booksize
2.13 Line connection variants
Booksize power units
Manual, (GH2), 06/2008, 6SL3097-2AC00-0BP6
123
Example 1
u
k
matching transformer = 3%,
S
K plant
= 50,000 kVA
S
K line
= 16 kW • 70 • 0.73 = 820 kVA
According to a)
S
n1
= 1.27 • 16 kW = 21 kVA
According to b)
N9$
N9$ವN9$ವ
N9$N9$ವ
6
Q

S
n2
> S
n1
⇒ S
n2
is decisive
The matching transformer requires a rated power S
n
of 25 kVA at a u
k
of 3%.
Example 2
u
k
matching transformer = 1%,
S
K plant
= 50,000 kVA
S
K line
= 16 kW • 70 • 0.73 = 820 kVA
According to a)
S
n1
= 1.27 • 16 kW = 21 kVA
According to b)
N9$
N9$ವN9$ವ
N9$N9$ವ
6
Q

S
n1
> S
n2
⇒ S
n1
is decisive
The matching transformer requires a rated power S
n
of 21 kVA at a u
k
of 1%.
Example 3
If S
K plant
is smaller, the transformer must be stronger
u
k
matching transformer = 3%,
S
K plant
= 3,000 kVA
S
K line
= 16 kW • 70 • 0.73 = 820 kVA
According to a)
S
n1
= 1.27 • 16 kW = 21 kVA
According to b)
N9$
N9$ವN9$ವ
N9$N9$ವ
6
Q

S
n2
> S
n1
⇒ S
n2
is decisive
The matching transformer requires a rated power S
n
of 34 kVA at a uk of 3%.