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Integration of IEC 60287 in Power System Load
Flow for Variable Frequency and Long Cable
Applications
X. Yuan, H. P. Fleischer, G. Sande, and L. J. Solheim
GE Oil and Gas, Norway, NO1338Norway Email: {xu.yuan, hans-peter.fleischer, gorm.sande, lars.joar.solheim}@ge.com
Abstract—AC resistance, usually paid less attention to than
inductance and capacitance during power system design
work, may cause significant deviation to true result if not
well controlled during load flow design for variable
frequency and long cable applications. In this paper, a load
flow scheme integrating cable design with power system
design is proposed, benefiting from IEC 60287. With thermal
consideration based on IEC 60287, AC resistances at load
current taking into account the longitudinal distribution of
current are iterated in a power load flow. Case results
demonstrated that the correct consideration of AC resistance
is critical to the derivation of true result. The proposed load
flow scheme naturally bridges the gap between cable
engineering and power system engineering and reduces the
uncertainty in system design work for variable frequency
and long cable applications.
Index Terms—load flow, variable frequency, submarine
cables, subsea power, wind power, mat power, IEC 60287
I. INTRODUCTION
Nowadays, more and more offshore wind farms are
being or going to be connected to grid with a distance of
over 150km. With today‟s manufacturing capability of
high voltage XLPE insulated three-core submarine cable
and the robustness of AC system, AC transmission
solution with long HVAC cable is still the first choice to
be evaluated, with an emphasis on the investment cost as
well as cost of transmission losses. Small difference in the
transmission losses over long cables could lead to large
differences in energy output over a 20 year life time [1],
which might further lead to a wrong picture when
comparing the different transmission alternatives.
Another emerging demand for long power cables comes
from the development of subsea oil pumping and gas
compression, which requires MW level of power for each
subsea consumer with step-out distance ranging from tens
of kilometers to a couple of hundred kilometers. In
addition to long submarine cables, the application usually
requires variable speed drives (VSDs) located on the
offshore production platform which introduces variable
frequency operation (up to 200Hz for high power subsea
compressor motors) over long cables [4], [5].
Manuscript received September 4, 2012; revised December 24, 2012.
Due to the dominantly capacitive characteristic of long
submarine cables, coupled with varying frequency, careful
consideration of current distribution in the cable and
reactive compensation strategy becomes vital when
designing the system in a steady state load flow domain.
The fact that cable engineers and electrical system
engineers usually work as two separate disciplines also
calls for an integrated methodology when performing a
power system load flow analysis.
In this paper, a load flow scheme directly integrating
cable design based on IEC 60287 is proposed. Its
implementation with power system load flow is based on
Matpower Version 4 [3]. Results show that a proper
consideration of cable design, current distribution along
cable and reactive compensation strategy altogether has
vital contribution to power system load flow design for
variable frequency and long cable applications.
II. PROBLEM FORMULATION
The motivation of the proposed load flow scheme
comes from the previously mentioned industrial
applications and more specifically described as the
following 3 main areas:
A. Loss Evaluation for Offshore Wind Farms
Offshore wind power is connected to onshore grid by
submarine cables and this distance can be up to 150km or
more, shown in.
GridOffshore
Substation
Offshore wind
Long submarine cable
Figure 1. Offshore wind grid connection via long AC cable.
Reactive power compensation is used either onshore or
at both ends of the cable. Due to the intermittent intrinsic
of wind power generation, remarkable variations of
current present in the compensated long cable. H.
Brakelmann in [1] proposed to derive the transmission
losses of the power cable taking into account the
longitudinal distributions of current and temperature:
6
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishingdoi: 10.12720/ijoee.1.1.6-11
𝑷𝑳𝒐𝒔𝒔 =𝑷𝑰𝒎𝒂𝒙
𝒍𝟎∙
𝑰𝟐(𝒙)
𝑰𝒏𝟐(𝒙)
∙ 𝒗𝜽(𝒙) ∙ 𝒅𝒙𝒍𝟎𝒙=𝟎
(1)
Where 𝐼𝑛 is the current rating of the cable and 𝑃𝐼𝑚𝑎𝑥 is
the nominal ohmic losses of the cable for 𝐼𝑛 . 𝑣𝜃 is the
calculated correction factor considering an ambient
temperature for a specific 𝐼. The above calculation assumes that the actual current
flowing along the cable has been determined, in other
words, the transmission system has been designed.
However, ideally as early as when designing the
transmission system, the variation of currents – in fact the
variations of resistances due to variations of current, shall
already be considered in the load flow design. And by
doing so, the calculation of power losses will then be
straightforward – difference in MW between cable input
and output.
This idea indicates the need of a load flow scheme that
integrates the variations of resistances along the cable due
to temperature dependence so that the loss evaluation can
be facilitated as a standard direct output from the load flow
design.
B. System Design for Power Distribution with Long
Cables
More and more offshore platforms and subsea stations
are requiring power (up to 50MW) from land remotely via
long submarine power cables (over 100km) for the
Oil&Gas industry [4]. Due to tough environment and
limited space, reactive compensation is preferred to be
done at one end onshore. Such a system is shown in Fig. 2.
Onshore/Platform Subsea transformer
Subsea Switchgear
Long submarine cable
M
M
M
M
Subsea VSD
STATCOM
Figure 2. Power distribution with long cable.
The design of such a system requires close look at the
voltage and current along the cable as well as loss
evaluations for different AC solutions and DC solutions.
C. System Design for VSD Driven Motor with Long
Cables
Applications of VSDs on large induction motors are not
new in the power industry. However, most applications for
subsea electrification involve a step-out distance,
requiring long cables between the motor and VSD[8].
Such a system is shown in Fig. 3.
Subsea Motor
Variable frequency over long cable
Topside VSD
M
Figure 3. VSD driven large motor with long cable step-out.
This long cable turns a direct VSD driven system to a
„variable frequency transmission system‟ due to the fact
that power system load flow is required to determine cable
size, transmission voltage and power losses. Furthermore,
variable frequency adds to the dimension of the design
which affects the voltage profile on the long cable.
Coupled with higher frequency (than 50Hz) output from
the VSD (up to 200Hz) and ambient situation of submarine
cables, the AC resistance of the cable becomes puzzling
yet vital to the correct derivation of system load flow
results.
III. METHODOLOGY
As stated, a load flow scheme directly integrating cable
design based on IEC 60287 is proposed. Previously, work
on estimating cable ampacity had been discussed a lot
however without looking at a power system impact [9],
[10]. This scheme is to bring power system design and
submarine cable design together. Power system load flow
highly depends on the RLC values of the long cable
presenting in the system. Power loss in particular is
relevant to the resistance value. While these values are
indeed available from cable manufacturer‟sdatasheet, only
DC resistances are usually provided. The actual operating
temperature of the cable is also not known beforehand
since it depends on the power losses (currents) and the
thermal conditions of submarine cables. And the currents
along the cable can vary remarkably. Therefore
traditionally during power system load flow, it is not
straight forward to take all these factors into consideration.
Newton Raphson Load Flow iterations
AC ResistancesL, C
Proximity Effect
Skin Effect
Define Power System Topology
Cable Geometric Design
Loss Factors
Define Power System Parameters
Select Cable
Cable Loading OK?
Vo
ltag
e &
C
urre
nt
No
Voltage Profile OK?
Ye
s
No
Environmental Conditions
Current
Temperature
END
Cable Ampacity
Figure 4. Flow chart of the proposed load flow scheme.
The actual AC resistances at steady state along the cable
vary and shall be calculated with skin effect, proximity
effect and the actual conductor temperatures which are not
known without thermal calculation. The proposed load
flow scheme incorporates cable geometrics and adds
additional iterations to the load flow core by updating the
7
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishing
AC resistance according to the longitudinal currents in the
cable. It has to run outside the Newton Raphson iteration
since it also affects reactive power compensation for the
cable. The thermal calculation is performed based on IEC
60287 in which an analytical method of calculating
thermal condition, skin effect and proximity effect is
presented [11], [12].
A flow chart of the proposed load flow scheme is
presented in Fig. 4.
The initiation of load flow is achieved by using either
the maximum AC resistance at 90°C which is derived
from a cable ampacity calculation, or the AC resistance at
base load current derived from thermal calculation. The
base load current can be derived simply by the load
apparent power (MVA) and the defined transmission
voltage (kV). The additional iterations update the AC
resistances according to the line currents derived from the
load flow. This outer loop of iterations will converge
within 3 rounds.
For the 3 main industrial applications mentioned in this
paper, most of the cables used are three-core submarine
cable with separated sheath and common armouring.
Therefore for this work, the „SL‟ type in IEC 60287 is the
most relevant. However, the proposed load flow scheme
can adapt to any type of cable geometry design and
formation.
IV. IMPLEMENTATION
The implementation of the proposed load flow scheme
is in Matlab with Matpower Version 4 modified as its load
flow core. The major building blocks for implementing the
proposed load flow scheme are discussed below.
A. Matpower
Matpower is a Matlab-based tool widely used in
research and education for AC, DC and optimal power
flow simulations. It consists of a set of M-files designed to
give the best performance while keeping the code simple
to customize [3]. Newton-Raphson, Fast-decoupled and
Gause-seidel method are optional for AC power flow
analysis which are not discussed in this paper and can be
referred to [3].
B. Cable Modelling
Long cables are modeled with „Pi‟ sections with lump
parameter for every kilometer. This is more than sufficient
for power flow analysis with frequency up to 200Hz. And
in this way the longitudinal current distribution is directly
considered. Cable capacitances are modeled as shunt
susceptances 𝐵sh . Each connecting point is treated as one
„PQ‟ bus. The derivation of cable inductance and
capacitance comes from cable geometry and its
installation method pre-calculated in a cable database.
This facilitates the integration of cable design into power
system design. It is also noted that this cable geometry
shall involve detailed design information of cables, i.e. the
thicknesses and material properties of all layers. AC
resistances, usually paid with less attention by power
system engineers, are iteratedby thermal calculation based
on IEC 60287.
C. Reactive Compensation
Active reactive compensations (FACTS devices) are
frequently applied in the 3 industrial applications
mentioned. In this work, steady state STATCOM is
modeled with additional PV bus connected to its
controlling bus via a coupling reactance. Due to the fact
that industrial power supply often utilizes OLTC for
voltage control for remote buses, reactive control mode is
used for STATCOM in this work to control the power
factor at grid connection point. Therefore, the generating
voltage at the additional bus is tuned to give a unity power
factor at grid connection point with its principle given by
where the angular difference is neglected according to the
steady state model given in Fig. 5.
𝑸 =𝑼(𝑼−𝑬)
𝑿𝑺𝑻 (2)
VSC
Controlled Bus
Additional Bus
U,Ɵ
E,Ɵ’
XST
Figure 5. Steady state modeling of STATCOM.
Correct implementation of reactive compensation is
vital in such applications since it directly affects the
current drawn in the cable.
D. IEC 60287
IEC 60287 is applicable to the conditions of steady state
operation of cables at all alternating voltages buried
directly in the ground, in ducts troughs or in steel pipes,
both with and without partial drying-out of soil, as well as
cables in air [11] and [12]. It provides analytical formulae
for current rating and losses leaving certain parameters
open such as material properties, ambient conditions and
burying depth. Skin effect, proximity effect, screen losses
and armouring losses are considered for different cable
formations. For submarine power cables, the most
important environmental inputs to the AC resistance value
are the thermal resistivity of soil, the buried depth as well
as the seabed temperature.
V. CASE RESULTS
Three different case results are derived to demonstrate
the influence from AC resistances for the 3 applications
mentioned. Each calculation is performed with three
different types of AC resistances:
𝑹𝟏 , which represents a constant „guessed‟ value
without considering cable condition and
longitudinal current distribution. In fact, a
maximum AC resistance is used.
𝑹𝟐, which represents a constant value considering
cable thermal condition based on IEC 60287. In fact,
8
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishing
an AC resistance calculated from base load current
is used.
𝑹𝟑 , which represents „true‟ AC resistances
considering both cable thermal condition and
longitudinal current based on IEC 60287.
A. Case Result 1 – Power Distribution with Long
Cables
The first case result is derived from the proposed load
flow scheme for the system given in Fig. 2.
TABLE I. CASE RESULTS 1 – POWER DISTRIBUTION WITH LONG
CABLES
150km, 50Hz, 20MW, 5Mvar (full load)
72.5kV rated, 3×240mm2 cable
66kV operation, OLTC 1.04 to control load end voltage
30MVA onshore transformer, 30MVA subsea transformer
AC
resista
nce
Cable end
voltage
(kV)
STATCO
M (Mvar)
STATCO
M voltage
Cable
loss
(MW)
R1 67.40 26.87 -0.0897 p.u. 2.221
R2 68.54 27.61 -0.0898 p.u. 1.753
R3 68.49 27.55 -0.0898 p.u. 1.787
According to the results summarized in Table I, the
differences in reactive compensation caused by different
AC resistances are minor. However, differences in voltage
and cable loss are not negligible. Considering 𝑅3as „true‟
value, the cable end voltage has nearly 1kV deviation with
approximately 20% difference in resistance (𝑅1).
Figure 6. AC resistances along the cable (R1, R2 and R3) – case result 1.
Figure 7. Voltage along the cable derived with different R–case result
1.
Cable loss deviates from „true value‟ correspondingly.
𝑅2 generates very close results to 𝑅3 indicating that the
longitudinal current distribution is not important for this
case. This is due to the balanced cable current sized for full
load condition.
Figure 8. Power losses along the cable derived with different R – case
result 1.
According to Fig. 7, the voltage profile over the entire
length of cable based on 𝑅1 deviates significantly from
„true value‟ based on 𝑅3, to an extent that it could result in
redesign. It also demonstrates the need of correct
consideration of resistance s in a controlled manner.
B. Case Result 2–Power Distribution with Long Cables,
Light Load
The second case result is derived in the same way as in
the first case but with half load. Results are summarized in
Table II.
TABLE II. CASE RESULTS 2 – POWER DISTRIBUTION WITH LONG
CABLES WITH LIGHT LOAD
150km, 50Hz, 10MW, 2.5Mvar (half load)
72.5kV rated, 3×240mm2 cable, inner layer
66kV operation, OLTC 0.97 to control load end voltage
30MVA onshore transformer, 30MVA subsea transformer
AC
resistanc
e
Cable end
voltage
(kV)
STATCO
M (Mvar)
STATCO
M voltage
Cable
loss
(MW
)
R1 66.01 28.42 -0.0953 pu 1.537
R2 66.65 28.77 -0.0953 pu 1.194
R3 66.59 28.73 -0.0953 pu 1.243
As a response to reduced load, OLTC has a low position
(0.97) to control the voltage. According to Table II, cable
loss deviates more than in the full load case. This confirms
the needs to consider both longitudinal distribution of
current and time (load) dependence of power flow stated in
[1] for the loss evaluation of wind power. It also applies to
the other two industrial applications where the load
requirement changes dramatically over years.
One thing worth noting is that reactive compensation
plays an important role in the longitudinal current
distribution and in our case result, one-end compensation
is used. This causes larger differences in current between
the two ends of the long cable. Double-end compensation
shall give more balanced current and thus give smaller
difference in cable loss calculated with a constant
resistance (i.e. 𝑅2).
0 50 100 1500.075
0.08
0.085
0.09
0.095
0.1
0.105
cable length in kilometers
AC
res
ista
nce
in
oh
m/k
m
R1
R3
R2
0 20 40 60 80 100 120 140 16067
67.5
68
68.5
69
69.5
70
Cable length in kilometers
Vo
ltag
e m
agn
itu
de
in k
V
with R3
with R2
with R1
0 50 100 1500.005
0.01
0.015
0.02
0.025
0.03
0.035
Cable length in kilometers
Act
ive
po
wer
lo
sses
in
MW
/km
with R3
with R2
with R1
9
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishing
Figure 9. AC resistances along the cable (R1, R2 and R3) – case result 2.
Figure 10. Voltage along the cable derived with different R – case result
2.
Figure 11. Power loss along the cable derived with different R – case
result 2.
C. Case Result 3– VSD Driven Motor with Long Cable
The third case result is derived for application of VSD
driven motor with long cable illustrated in Fig. 3. Results
are summarized in Table III.
Based on the results summarized in TABEL 3, a „wrong‟
resistance value 𝑅1 (15% deviation from „true value‟
according to Fig. 12.) may lead to very large differences in
voltage profile across the cable (10% deviation). Similarly,
the value of reactive power through the VSD is also
subjected to a large „error‟ due to large deviation of
voltage profile shown in Fig. 13. This provides more
evidence that the AC resistance value needs to be taken
care of in a well-controlled manner from the beginning of
engineering design, for this specific type of application.
Due to the fact that no reactive compensation is used in
such systems, current along the cable is quite balanced and
hence the longitudinal distribution of current is not critical
(difference between 𝑅2 and 𝑅3). This type of application
has variable voltage output (from VSD) to operate at
different loading. Therefore, the time (load) dependence of
power flow is not examined.
TABLE III. CASE RESULTS 3 – VSD DRIVEN MOTOR WITH LONG
CABLE
70km, 200Hz, 10MW, 5Mvar (full load)
52kV rated, 3×240mm2 cable
30kV operation
30MVA onshore transformer, 15MVA subsea transformer
AC
resistanc
e
Cable send
end voltage
(kV)
Cable
receive end
voltage
(kV)
VSD var
(Mvar)
Cable
loss
(MW)
𝑹𝟏 30.49 27.28 5.80 1.130
𝑹𝟐 30.75 30.24 8.33 0.908
𝑹𝟑 30.75 30.29 8.36 0.904
Figure 12. AC resistances along the cable (R1, R2 and R3) – case result 3.
Figure 13. Voltage along the cable derived with different R – case result
3.
Figure 14. Power loss along the cable derived with different R – case
result 3.
0 50 100 150
0.075
0.08
0.085
0.09
0.095
0.1
Cable length in kilometers
AC
res
ista
nce
in
oh
m/k
m
R1
R3
R2
0 20 40 60 80 100 120 140 16063.5
64
64.5
65
65.5
66
66.5
67
Cable length in kilometers
Vo
ltag
e m
agn
itu
de
in k
V
with R1
with R2
with R3
0 50 100 1500
0.005
0.01
0.015
0.02
0.025
0.03
Cable length in kilometers
Act
ive
po
wer
lo
sses
in
MW
/km
with R1
with R2
with R3
0 10 20 30 40 50 60 700.096
0.098
0.1
0.102
0.104
0.106
0.108
0.11
0.112
0.114
Cable length in kilometers
AC
res
ista
nce
in
oh
m/k
m
R1
R3
R3
0 10 20 30 40 50 60 70 8027
28
29
30
31
32
33
Cable length in kilometers
Vo
ltag
e m
agn
itu
de
in k
V
with R1
with R2
with R3
0 10 20 30 40 50 60 700.008
0.01
0.012
0.014
0.016
0.018
0.02
0.022
Cable length in kilometers
Act
ive
po
wer
lo
sses
in
MW
/km
with R1
with R2
with R3
10
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishing
VI. FURTHER WORK
The practice for designing power system starts with
load flow sizing cable and reactive compensation strategy
(voltage regulations). Following this, fault calculation and
time domain simulations (EMTP type) are done to specify
protection and transient related parameters. The proposed
load flow scheme in this paper gives realistic pictures of
„pre-fault‟ states of the long cable transmission system and
the line resistances can be directly used in other
calculations following the load flow calculation.
Applications could also be extended to power system
operations.
Some other research work on submarine power cables
[10] raised questions about the loss calculation defined by
IEC 60287 based on measurements and finite element
methods. However, it is more product-oriented and an
analytical method facilitates the interface towards power
system engineering and it can be modified to meet
accuracy requirement.
Last but not least, the 3 types of industrial applications
discussed in the paper often involve large harmonic
contents due to the presence of power electronics. Current
harmonics in the cable results in additional conductor
heating hence higher conductor temperature [13]. This
factor is not considered in IEC 60287 but it can be taken
into account by superposition of temperature rise for the
specific harmonic orders, once derived from a harmonic
analysis.
VII. CONCLUSION
It is proposed that the IEC 60287 standard be directly
integrated into power system load flow in order to achieve
well-controlled results for the 3 industrial applications
with presence of long cables and/or variable frequency.
Case results have demonstrated the importance of AC
resistances. Wrong resistance value could lead to very
different voltage profiles (system design) and the
longitudinal distribution of currents along cable need to be
taken into account when the system is compensated at one
end and in particular for light load operation with long
cables.
The proposed load flow scheme integrates cable design
based on well-established standard with power system
design so that they are no longer decoupled processes by
themselves which reduces uncertainty and increases
observability of industrial power system design work.
Further work, such as the harmonic current superposition
can also be included in the thermal calculation.
ACKNOWLEDGMENT
The author would like to acknowledge the creators of
„MATPOWER‟, who facilitate research work in the area
of power system steady state operation, planning and
analysis work through open source programs.
REFERENCES
[1] H. Brakelmann, “Efficiency of HVAC power transmission from offshore windmills to the grid,” in Proc. IEEE Bologna Power
Tech Conference, 2003.
[2] N. B. Negra, J. Todorovic, and T. Ackermann, “Loss evaluation of HVAC and HVDC transmission solutions for large offshore wind
farms,” Elsevier Electric Power Systems Research, vol. 76, iss.11,
pp. 916–927, Jul. 2006. [3] R. D. Zimmerman, C. E. Murillo-Sánchez, and R. J. Thomas,
"MATPOWER steady-state operations, planning and analysis
tools for power systems research and education," IEEE Transactions on Power Systems, vol. 26, no. 1, pp. 12-19, Feb.
2011.
[4] H. Gedde, B. Slåtten, E. Virtanen, and E. Olsen, “Ormen lange long step-out power supply,” in Proc. Offshore Technology
Conference, 2009, paper OTC 20042.
[5] E. Baggerud, V. S. Halvorsen, and R. Fantoft, “Technical status and development needs for subsea compression,” in Proc.
Offshore Technology Conference, 2007, paper OTC 18952.
[6] G. E. Balog, N. Christl, G. Evenset, and F. Rudolfsen, “Power
transmission over long distances with cables,” in Proc. CIGRE
Session 2004, paper B1-306.
[7] T. Hezel, H. Baerd, J. J. Bremnes, and J. Legeay, “Subsea high voltage power distribution,” in Proc. IEEE PCIC, 2011.
[8] G. Scheuer, B. Monsen, K. Rongve, T. E. Moen, E. Virtanen, and
S. Ashmore, “Subsea compact gas compression with high speed VSDs and very long step-out cables,” in Proc. IEEE PCIC Europe,
2009.
[9] D. G. A. K. Wijeratna, J. R. Lucas, H. J. C. Peiris, and H. Y. R. Perera, “Development of a software package for calculating
current rating of medium voltage power cables,” in Proc. Trans.
IEE Sri Lanka, 2003 [10] R. Stølan, “Losses and inductive parameters in subsea power
cables,” M. Sc. thesis, Norwegian university of science and
technology, Trondheim, Norway, Jul. 2009. [11] Electrical Cables – Calculation of the Current Rating – Current
Rating Equations and Calculation of Losses, IEC60287-1-1,
2006-12. [12] Electrical Cables – Calculation of the Current Rating – Thermal
Resistance, IEC 60287-2-1, 2006-05. [13] A. Hiranandani, “Calculation of Cable Ampacities including the
Effects of Harmonics,” IEEE Industry Applications Magazine,
1998.
X. Yuan was born in Jiangsu, China in 1983. He
holds a BSc. and a MSc. degree (2005 and 2011) in
electric power engineering from Hohai University in China and the Royal Institute of Technology in
Sweden respectively. He started his professional
career with FMC Technologies in Norway in 2008 working on subsea power system projects. He
joined GE Oil&Gas Norway in 2010 and is now a
Lead Electrical Engineer in the Subsea Power Systems and Products department where he has been highly involved in the power system
design for subsea applications. His interest is in power system
engineering and power electronics. He has been a member of IEEE
since 2011.
G. Sande was born in Norway in 1964. He received
his MSc degree in 1987 and his PhD degree in
1993, both from Department of Electrical Power Engineering, Norwegian University Science and
Technology. In 1993 he took a position as
Researcher at ABB Corporate Research in Norway where he stayed until 2006. From 2006 to 2010 he
worked with development of electrostatic coalescer
equipment (oil-water separation) in Aibel Technology and Products. In 2010 he took a position as Senior Engineer in GE Oil & Gas, Subsea
Power Systems and Products where he has been leading several power
system studies, contributing to power product development and responsible for electrical testing technologies for GE Oil & Gas
Norway
11
International Journal of Electrical Energy, Vol.1, No.1, March 2013
©2013 Engineering and Technology Publishing