FITformer® ACT
Amorphous core material for extremely low no-load-losses
Whereas earlier cost optimization approaches considered
only the purchase price, the trend is now toward analyzing and optimizing of goods with regard to their operating
costs (“total cost of ownership“). This is meaningful with
respect to business management and also places a greater
focus than ever on environmental aspects.
Higher energy costs, more stringent loss specifications
(e.g., the EU Ecodesign Directive) and expensive CO2 costs
all lead to an ever-increasing demand for extremely low
losses. Distribution transformers with extremely low
losses can be fabricated both through optimized design
or the use of enhanced materials, as well as by employing
particularly low-loss core material.
Savings potential for no-load losses
Local grid transformers in particular are often operated on
average at less than 40% of their rated load. At these low
loads, the percentage of load losses for the total losses is
likewise low. No-load losses are therefore decisive.
In rated operation, the efficiency level for a transformer
is approx. 99%, i.e., the percentage of potential savings is
low. However, when the total installed capacity and the
associated losses are considered, the savings provided
by even a small improvement in efficiency are substantial.
If, for example, the annual demand for local grid transformers were met with 50% less no-load losses, around
42 GWh could be saved, thus reducing CO2 emissions by
24,000 metric tons.
Losses depending on transformer load
8000
7000
6000
Loss Pv [W]
Reduced losses for optimized operating costs
5000
4000
3000
2000
1000
0
0
100
200
300
400
500
600
S [kVA]
No-load loss [W]
Load loss [W]
Total loss [W]
Diagram: Load and no-load losses for a local grid
transformer
siemens.com/transformers
Properties of amorphous core material
Special features of the FITformer® ACT
The randomly arranged molecular structure of amorphous
core material results in less friction than traditional silicon
iron cores when magnetized. This unique property facilitates magnetization and de-magnetization and yields significantly lower remagnetization losses in amorphous
materials. The extreme thinness of the material also provides lower eddy current losses.
The FITformer® ACT by Siemens fulfills all customer
requirements and type tests needed in regard to shortcircuit strength/partial discharge through a special transformer design: The windings are mechanically detached
from the core, which safeguards the core from any
mechanical loading.
Amorphous core laminations are fabricated by rapidly
cooling an iron-based molten alloy within one-ten-thousandth of a second. This material then provides extremely
low specific losses of 0.22W/kg at 1.3T induction. The foil
that is produced is extremely thin and is rolled directly
onto the component. Processing of the 25-micrometerthin and brittle foil is complicated, as it may not be
exposed to any stress or mechanical loading. Conven­
tional core installation technology used in Europe cannot
be performed with this material. Instead, transformers
with amorphous core material are designed with a wound
core, as is standard practice on the American market.
Special processing of the brittle, amorphous material and
protection offered by covers ensure the mechanical stabilization of the core. Consequently, there is no risk of partial discharge.
Despite all of the economic benefits provided by this
material, special consideration must still be given to the
installation location of the transformer; for magnetostriction and magnetization-induced expansion and constriction of the laminations can lead to bigger overall dimension and an increase in the noise generated in the
transformer.
Savings potential thanks to amorphous core material
The higher purchase price of a distribution transformer
with amorphous core lamination is offset over a short
period, thanks to its very low losses. The environment
also wins: For a 630 kVA transformer, 71 metric tons of
CO2 are saved over an operating period of 30 years.
Main features:
• Liquid-immersed distribution transformers;
hermetically sealed
• 3-phase, 50 Hz, Dy-connection
• Sn: 100… 1000 kVA
• HV 10, 20, 30 kV
LV: 400, 410, 420 V
Design impedance voltage: 4% (6%)
• Load losses: Ak, Bk, Ck
• No-load losses: A0-50%
• Noise level: based on loss category B0,
or “as low as possible”
• Design based on regionally predominant standards
(IEC or ANSI/IEEE)
Remarks
Transformer 1
Eco-Design
Transformer 2
FITformer ACT
Standard A0/Ck
ACT A0-50/Ak
Loss
Difference
630
SN
P0
600
300
300
Load losses [W]
PK
6,500
4,600
1,900
Transformer price [€]
A
6,300
8,190
Average Load [%]
Load
30 %
Operation time [h/year]
TB
8,760
Yearly interest
[%/year]
p
2%
Amortisation period commercial
[years]
n
10
Energy cost [Cent/kWh]
SP
Raise of energy cost [Cent/
(kWh*year)]
ΔSP
Period under review [years]
tB
alterable values
Transformer rating [kVA]
No load losses [W]
10
0.05
30
Transformer 1
Transformer 2
kS
0.1075
Interest factor
q
1.02
Amortisation factor
r
Capital cost [€/year]
kA
701
912
Cost for no load losses [€/year]
KP0
565
283
2628.0
No load losses
kWh/year
Cost for load losses
[€/year]
KPk
551
390
1498.0
Load losses
kWh/year
Total investment [€]
KI
7,014
9,118
123.8
Loss savings MWh/
Period under review
Total costs for losses
[€/year]
KV
1,116
672
0.576
Factor t/MWh
71.3
to CO2 savings during
period under review
Higher investment [€]
ΔKI
Reference trafo
2,104
Saved cost for lower losses [€/year]
ΔKV
Reference trafo
–444
Period for total
amortisaton [years]
x
Reference trafo
4.7
calculation
Energy cost in [€/kWh]
Result: Eco-Design related to FITformer ACT: Transformer 2 amortized after 4.7 years
Published by and copyright 2016:
Siemens AG
Energy Management Sector
Freyeslebenstrasse 1
91056 Erlangen, Germany
For more information, please contact
our Customer Support Center.
Phone: +49 180/524 70 00
Fax:
+49 180/524 24 71
(Charges depending on provider)
E-mail: support.energy@siemens.com
Energy Management Division
Transformers
Article No. EMTR-B10013-00-7600
Dispo 19200
fb 7054 0116
siemens.com/transformers