Technical Specification-35kV-rev2.doc

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					  CAPE WIND ASSOCIATES LLC

33 kV Solid Dielectric Submarine Cable

         Technical Specifications
                  Revision 2
                 January 2004
                                       Table of contents
                                                            Page No.

1.      OFFER DOCUMENTATION – CABLE DATA                           4
1.1     Proposal general description                               4
1.2     Thermal design                                             4
1.3     Electrical design                                          5
1.4     Mechanical design                                          5

2.      ELECTRICAL, ENVIRONMENTAL AND INSTALLATION PARAMETERS      6
2.1     Electrical design data                                     6
2.2     Environmental                                              6
2.3     Installation                                               6

3.      GENERAL DESCRIPTION OF THE PROPOSED CABLE SYSTEM           7
3.1     Conductor                                                  7
3.2     Conductor screen                                           7
3.3     Insulation                                                 8
3.4     Insulation screen                                          8
3.5     Longitudinal water barrier                                 8
3.6     Wire screening                                             8
3.7     Longitudinal water barrier                                 8
3.8     Anti-corrosion sheath                                      8
3.9     Assembly                                                   8
3.10    Armor bedding                                              9
3.11    Armor                                                      9
3.12    Serving                                                    9
3.13    Overall cable marking                                      9
3.14    33 kV submarine cable drawing                            10

4.      SYSTEM LAYOUT                                            11

5.      ACCESSORIES                                              12
5.1     Main items                                               12
5.1.1   Armor hang-off                                           12
5.1.2   Clamps                                                   12
5.1.3   Plug-in connectors                                       12
5.1.4   Silicon termination                                      12
5.1.5   Pigtails                                                 12
5.1.6   Sealing device                      12
5.1.7   Pulling heads                       12
5.2     Optional items                      13
5.2.1   Optical patch panels and cabinets   13
5.3     Spare parts (required)              13
5.4     Accessory drawing list              13

6.      TESTS                               14
6.1     Factory testing                     14
6.2     Tests after installation            17

7.      CABLES RATED POWER AND LOSSES       31
1. OFFER DOCUMENTATION – CABLE DATA


1.1        Proposal general description

This section details the cable and system design proposal relevant to the medium voltage submarine
composite cables and their relevant accessories, necessary for the completion of the Cape Wind
Offshore wind farm project, located in the Nantucket Sound.

According to your Technical Specification documents, our scope of supply includes the design,
manufacture, factory testing, delivery, installation and commissioning of the submarine cables and
their relevant accessories.
The proposed wind park layout is enclosed in item 5.
The submarine cables will be buried along the entire route length, in accordance with item 2 of
this document.
The cable design is based on the operating parameters and the electrical, environmental and
installation conditions stated in item 2 of this document.

Our previous proposals (rev. 0 and rev. 1), were fully based on your technical specification, which
calls for lead sheathed cables.
For this revision 2, basing on the state of the art for medium voltage submarine cables, we are
offering a modified design, which still guaranteeing the suitable level of reliability required for
these types of systems, allows to reduce the overall system cost.
The cable design is a 35 kV, three-core, copper conductors, XLPE insulated, copper wire screened,
polyethylene jacketed and single wire armored composite submarine cables, inclusive of one (1)
interstitial optical unit equipped with 24 single mode ITU-T G.652 fibers.
The cable main constructional characteristics are fully compliant with the requirements stated in
your Technical Specification, unless for the lead sheath which is replaced by a copper wire screen,
and complies mainly with the rules laid down by AEIC and ICEA standards, where applicable
As required a maximum of three (3) cable sizes have been considered.

As for the 115 kV system, we have considered the results obtained from the marine survey
campaign (0.5 Kxm/W and 19 °C instead of previous 0.8 Kxm/W and 17 °C) as design data for
this proposal.

1.2        Thermal design

The thermal design has been carried out considering the worst thermal conditions and assuming the
following maximum conductor temperatures:

-     90 °C for normal operating condition
-     250 °C for short circuit condition

Thermal calculations have been performed for the Nominal Load Condition and for Emergency.
The calculation method is shown in the IEC recommendation 60287 "Calculation of the
Continuous Current Rating of Cables (100% load factor)".
The short circuit calculations have been carried out according to IEC recommendation 949
“Calculation of thermally permissible short circuit currents, taking into account non-adiabatic
heating effects”.
The assumptions taken for thermal design calculations are those mentioned in item 2 of this
document.
Please note that the requirement for carrying a three-phase fault current of 40 kA for 30 cycles
cannot be met for the 150 mm2 cable size.
Nevertheless, the above fault level is expected to occur at the ESP and the effective fault level at the
WTG should be lower than the above figure.
The conductor and screen fault performances are stated in the attached Proposal Form IV Technical
“34.5 kV Submarine Cable A”, “34.5 kV Submarine Cable B” and “34.5 kV Submarine Cable C”.

1.3      Electrical design

According to AEIC CS5-94 standard, the nominal insulation thickness is set to 8.76 mm for all
cable sizes, corresponding to a 35 kV, 100% insulation level.

1.4      Mechanical design

The mechanical design of the submarine cables consist in the verification of the mechanical stresses
to which each layer is subjected.
All main cable components have been calculated in such a manner as to give rise to acceptable
stresses during manufacturing, loading, transport, laying, service and recovery.
As far as the intrinsic cable mechanical protection is concerned, we have provided a wire
armoring protection in the form of a single layer of 5 mm diameter galvanized steel wires.
In our opinion, this type of protection is suitable to ensure that the cable is able to withstand the
rigors of installation (tension, crushing and abrasion), and to guarantee the cable integrity against
the mechanical stresses deriving from the manufacturing handling.
As required, the cable will be protected along the entire route length by direct burying at the
specified burial depths.
2. ELECTRICAL, ENVIRONMENTAL AND INSTALLATION PARAMETERS

Here below, all parameters used for calculating cable system current ratings are listed.

2.1      Electrical design data

Rated r.m.s. AC nominal voltage between phases (U)                              kV          33 ± 10%
Basic Impulse Insulation Level (BIL)                                            kV                200
Rated frequency                                                                 Hz                 60
Number of wind turbines                                                         N°                130
Wind turbine maximum output at 33 kV                                            A                  70
Three-phase and single-phase short circuit current for 30 cycles at ESP         kA                 40
Neutral point of the system                                                          Solidly grounded

2.2      Environmental

Maximum temperature of seabed (at 6 ft depth)                                   °C                19
Seabed thermal resistivity (average radial)                                     K×m/W             0.5
Maximum air temperature (J-tube location)                                       °C                28
Maximum air temperature (indoor)                                                °C                30

2.3      Installation

Cable directly buried in the seabed:
Nominal burial depth (on top of the cables)                                     ft                  6
Cables installed in J-tube:
- internal diameter                                                             mm                280
- external diameter                                                             mm                300
Cables installed on ladders:
The three power cores will run separately on cable ladders
Minimum axial spacing between cores                                                  2 × core diameter
3. GENERAL DESCRIPTION OF THE PROPOSED CABLE SYSTEM

We are proposing 35 kV three-core, XLPE insulated and single wire armored cables, having the
construction hereunder briefly specified:

-     Stranded copper conductor (longitudinally sealed)
-     Extruded semi-conducting screen
-     XLPE insulation
-     Extruded semi-conducting screen
-     Longitudinal water penetration barrier
-     Copper wire screen
-     Longitudinal water penetration barrier
-     Polyethylene sheath
-     Lay-up with n° 1 optical unit and fillers
-     Armor bedding
-     Galvanized steel wire armoring
-     Overall serving

Overall cable sizes (approx.):

-   Conductor cross section                   (mm2)       3x150          3x400          3x630
-   Diameter                                   (mm)       115±1          136±1          151±1
-   Weight in air                             (kg/m)      21.5±1          31±1           41±1
-   Weight in sea water                       (kg/m)       13±1           19±1           25±1
-   Maximum number of WTG                                    5              8             10

The detailed description of the proposed cables is specified here below.
Further constructional details and performances are stated in the Proposal Form IV Technical
“34.5 kV Submarine Cable A”, “34.5 kV Submarine Cable B” and “34.5 kV Submarine Cable C”.

3.1        Conductor

The conductor offered is of compacted circular design, constructed from annealed copper wires
and longitudinally water sealed in order to reduce water migration within the conductor in case of
cable damage. They have a nominal cross sectional area of 150 mm2, 400 mm2 and 630 mm2 and
the design meets the requirements laid down by IEC 60228 Class 2 standard.
A semi-conducting binder tape may be applied over the conductor.

3.2        Conductor screen

A semi-conducting screen layer is extruded over the conductor.
3.3      Insulation

The insulation consists of XLPE compound and it is applied with a minimum average thickness
of 8.76 mm.

3.4      Insulation screen

A semi-conducting screen layer is extruded over the insulation.
The insulation shield is securely bonded to the insulation and requires the application of heat for
removal, thus assuring the consistent bond required at this important stress interface.

3.5      Longitudinal water barrier

Prior to the application of the metallic core screening, a longitudinal water barrier composed of
semi-conducting water swelling tapes is applied, thus limiting the water penetration along the
power core in case of cable damage.

3.6      Wire screening

One layer of bare annealed copper wires is helically applied over the longitudinal water barrier as
core metallic screen. This has a nominal cross section of 25 mm2 for the 150 mm2 core cross
section and 35 mm2 for the 400 mm2 and 630 mm2 core cross sections.
These cross sections represent our preliminary proposal and must be verified on the basis of the
actual short circuit figures.

3.7      Longitudinal water barrier

Prior to the application of the anti-corrosion sheath, a longitudinal water barrier composed of
water swelling tapes is applied, thus limiting the water penetration along the power core in case
of cable damage.

3.8      Anti-corrosion sheath

An extrusion of polyethylene compound is provided over each screened core.

3.9      Assembly

The three sheathed cores and the interstitial optical unit are laid up together using a planetary
type laying up machine, which avoids the imposition of torsion stresses on the sheathed cores.
Suitable fillers are included in the interstices to give a substantially round shape.
The assembled cores are bound together with a synthetic tape.
The interstitial optical unit description is stated in the attached document “INTERSTITIAL
OPTICAL UNIT FOR SUBMARINE COMPOSITE CABLES”.
3.10     Armor bedding

One layer of polypropylene strings or textile tapes is applied over the assembly as bedding for the
armor wires.

3.11     Armor

One layer of 5 mm diameter galvanized steel wires is applied over the bedding.
The application of bitumen is provided over the armor layer as further anti-corrosion protection
and to aid the adhesion of the overall serving.
Galvanizing is in accordance with the requirements of BS EN 10257-2.

3.12     Serving

One or two layers of polypropylene strings is applied over the armor as cable serving, to provide
a degree of abrasion protection and to reduce cable/skid friction during lay.
The polypropylene serving is applied with a double color pattern in order to give high visibility
to the cable and enable monitoring of cable horizontal movement by ROV cameras.

3.13     Overall cable marking

The cables will be provided with overall colored or numbered tapes applied over the serving at
regular intervals.
Our proposal is to apply a 100 m interval between tapes.
3.14    33 kV submarine cable drawing

                        (INDICATIVE ONLY – NOT TO SCALE)




Approximate overall sizes:
- Conductor cross section               (mm2)    3x150     3x400   3x630
- Diameter                               (mm)    115±1     136±1   151±1
- weight in air                         (kg/m)   21.5±1     31±1    41±1
- weight in sea water                   (kg/m)    13±1      19±1    25±1
5. ACCESSORIES

We give here below a brief description of the accessories necessary for the submarine cable circuit
completion and the optional items. Where available, further accessory details are shown on attached
typical drawings.

5.1      Main items

5.1.1    Armor hang-off

The armor hang-off offered is a mechanical clamped type, which is fitted after cable is cut to
length and pulled into the riser. It consists of a flange installed on top of the j-tube and a support
where the armor wires are bent and held.
This type of accessory is foreseen in order to lock the cable on top of the j-tube at the offshore
transformer platform (ESP) and at each wind turbine generator (WTG).

5.1.2    Clamps

Suitable aluminum cable clamps will be used in order to lock the cable power cores on ladders.
Similarly, cable clamps will also be provided for locking the interstitial optical unit on ladders.

5.1.3    Plug-in connectors

We propose both CONNEX plug-in connectors manufactured by Pfisterer and ABB.
These will be installed at the ESP switchgears.
Please refer to the technical description included in the attached brochures.

5.1.4    Silicon termination

Standard slip-on terminations are provided at each WTG’s switchgear.
Please refer to the technical description included in the attached brochure.

5.1.5    Pigtails

In order to allow the optical unit termination inside the WTG and at the ESP locations, we
provide optical pigtails, without connectors. The estimated pigtail length is 5 m.

5.1.6    Sealing device

In order to achieve the core sealing at the WTG entrance, we propose the sealing device shown in
the attached preliminary drawing ref. S1003710.

5.1.7    Pulling heads

Conventional “Chinese fingers” will be provided for pulling the cables through the J-tubes.
5.2        Optional items


5.2.1      Optical patch panels and cabinets

We propose to install at each WTG an optical termination as described in the attached brochure
UMDJ 9.0 & 9.3.
Jumpers will provide the fiber optic routing.

5.3        Spare parts (required)

-     m 1000 of 33 kV, 3x150 mm2 cable on steel reel
-     m 1000 of 33 kV, 3x400 mm2 cable on steel reel
-     m 1000 of 33 kV, 3x630 mm2 cable on steel reel
-     n° 4 repair splices for 33 kV, 3x150 mm2 cable
-     n° 4 repair splices for 33 kV, 3x400 mm2 cable
-     n° 4 repair splices for 33 kV, 3x630 mm2 cable
-     n° 6 plug-in connectors for 33 kV, 3x400 mm2 cable
-     n° 6 plug-in connectors for 33 kV, 3x630 mm2 cable
-     n° 12 silicon terminations for 33 kV, 3x150 mm2 cable
-     n° 12 silicon terminations for 33 kV, 3x400 mm2 cable
-     n° 12 silicon terminations for 33 kV, 3x630 mm2 cable
-     n° 4 pulling heads (Chinese fingers) for 33 kV, 3x150 mm2 cable
-     n° 4 pulling heads (Chinese fingers) for 33 kV, 3x400 mm2 cable
-     n° 4 pulling heads (Chinese fingers) for 33 kV, 3x630 mm2 cable
-     n° 12 hang-off devices (same J-tube size assumed for all cables)
-     n° 4 sealing devices for 33 kV, 3x150 mm2 cable
-     n° 4 sealing devices for 33 kV, 3x400 mm2 cable
-     n° 4 sealing devices for 33 kV, 3x630 mm2 cable

5.4      Accessory drawing list
The following accessory typical drawings and brochures are attached to this proposal:

-     Armor hang-off device
-     Clamp
-     Plug-in connector
-     Silicon termination
-     Submarine repair splice
-     Sealing device
-     Optical patch panel and cabinet
6. TESTS

The following testing program is our preliminary proposal, based on your Technical
Specification’s requirements and our experience in the design of submarine systems.
The submarine power cables shall be tested in accordance with the following standards (where
applicable):

-     Customer’s Technical Specification
-     AEIC CS5-94 "Specifications for Cross Linked Polyethylene Insulated Shielded Power Cables
      rated 5 through 46 kV”
-     ICEA S-66-524 “Cross-Linked Thermosetting Polyethylene Insulated Wire and Cable for the
      Transmission and Distribution of Electrical energy”
-     Manufacturer’s proposal

6.1       Factory testing

The test particulars and guarantees discussed in this part are stated in the following tables:

                                 Test                                           Reference table

    Electrical tests on manufacturing lengths before jointing and                   Table 1
    armoring
    Tests on the complete shipping length including factory                         Table 2
    installed joints
    Non-electrical production tests (Sample Tests)                                  Table 3

The nominal testing frequency is 50 Hz.
However, resonant systems (i.e. in the range 15÷60 Hz) may be used where necessary due to the
long lengths involved.
Where necessary, tests on samples may also be considered.
Unless otherwise stated, the test voltage shall be applied between the conductor and the metallic
screen.
                                            Table 1
            Electrical tests on manufacturing lengths before jointing and armoring

Test Description                                   Particulars and      Test Circuit Description
                                                    Guarantees
Conductor D.C. resistance test                                       On each manufacturing core
- D.C. resistance at 20 °C:                                          length
- 3x150 mm2                                        ≤ 0.1240 Ω/km
- 3x400 mm2                                        ≤ 0.0470 Ω/km
- 3x630 mm2                                        ≤ 0.0283 Ω/km
Partial Discharge Test                                               On core samples
- test level:                                          69 kV
- discharge magnitude                                  ≤5 pC
Voltage test                                                         On each manufacturing core
- A.C. test voltage for 5 minutes                      69 kV         length
Insulation resistance test
- Minimum value at 20 °C:
- 3x150 mm2                                        1980 MΩxkm
- 3x400 mm2                                        1430 MΩxkm
- 3x630 mm2                                        1170 MΩxkm



                                           Table 2
            Tests on the complete shipping length including factory installed joints

Test Description                                   Particulars and      Test Circuit Description
                                                    Guarantees
Conductor D.C. resistance test                                       On the complete production
- D.C. resistance at 20 °C                                           length      including     factory
(indicative only, because it is not possible to                      installed joints (if any)
know the actual conductor temperature that could
be very different along the cable length)
- 3x150 mm2                                        ≤ 0.1240 Ω/km
- 3x400 mm2                                        ≤ 0.0470 Ω/km
- 3x630 mm2                                        ≤ 0.0283 Ω/km
Insulation resistance test
- Minimum value at 20 °C:
- 3x150 mm2                                        1980 MΩxkm
- 3x400 mm2                                        1430 MΩxkm
- 3x630 mm2                                        1170 MΩxkm
High voltage test:
- Alternative 1: HVDC test for 15 min.                 125 kV
- Alternative 2: HVAC test for 5 min.                   69 kV
OTDR test on optical fibers                                          From both cable ends
- at 1550 nm (dB/km)                                   ≤0.25
                                                  Table 3
                               Non-electrical Production Tests (sample tests)

Test Description                                            Particulars and                     Test frequency
                                                             Guarantees
Conductor
DC resistance                                                ICEA S-66-524            100% of production lengths
Diameter                                                     ICEA S-66-524            On 1 sample from each end of
                                                                                      each manufacturing length
Non-metallic conductor shield
Aged elongation                                              ICEA S-66-524            On samples of material lot
Brittleness temperature                                      ICEA S-66-524            On 1 sample of material
Thickness                                                      AEIC CS5               AEIC CS5, Table A-2, Plan F
Voids and protrusions                                          AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Wafer boil                                                     AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Insulation
Physical and aging tensile and elongation                    ICEA S-66-524            AEIC CS5, Table A-2, Plan H
Hot creep                                                      AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Voids and contaminants                                         AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Insulation internal irregularity                               AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Diameter                                                       AEIC CS5               On both ends of each shipping
                                                                                      length
Shrink-back test                                               AEIC CS5               On 1 sample of material for
                                                                                      each extrusion run
Thickness and eccentricity                                     AEIC CS5               AEIC CS5, Table A-2, Plan F
Non-metallic insulation shield
Aged elongation                                              ICEA S-66-524            On samples of material lot
Brittleness temperature                                      ICEA S-66-524            On 1 sample of material
Thickness                                                      AEIC CS5               AEIC CS5, Table A-2, Plan F
Voids and protrusions                                          AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Wafer boil                                                     AEIC CS5               On 1 sample from each end of
                                                                                      each manufacturing length
Diameter                                                       AEIC CS5               On both ends of each shipping
                                                                                      length
Metallic screen
Dimensional measurements                                     ICEA S-66-524            AEIC CS5, Table A-2, Plan F
Jacket
Physical and aging tensile and elongation                    ICEA S-66-524            AEIC CS5, Table A-2, Plan H
Thickness                                                      AEIC CS5               AEIC CS5, Table A-2, Plan F

For technical particulars and guarantees, please refer to the relevant technical data sheets.
6.2        Tests after installation

The following tables summarize the testing procedures foreseen subsequently to the cable
installation and for the commissioning of the system.

                                        Test                                           Reference table

 Preliminary tests after installation                                                        Table 4
 Commissioning tests                                                                         Table 5

Unless otherwise stated, the test voltage shall be applied between the conductor and the metallic
screen.


                                                    Table 4
                                       Preliminary tests after installation

The following tests will be carried out on each installed cable length, before splicing and
termination.

 Test Description                                        Particulars and           Test Circuit Description
                                                          Guarantees
 Conductors continuity                                       Record             All tests will be carried out from
                                                                                one cable end only
 Metallic screens continuity                                 Record
 Optical unit copper tube continuity                         Record
 Insulation resistance test
 (minimum value at 20 °C)
 - 3x150 mm2                                              1980 MΩxkm
 - 3x400 mm2                                              1430 MΩxkm
 - 3x630 mm2                                              1170 MΩxkm
 OTDR test on optical fibers
 - at 1550 nm (dB/km)                                         ≤0.25
                                                        (indicative only)
 HVDC test for 5 minutes                                     94 kV
 (valid for all cable types)                         (75% of DC factory test)
                                                     Table 5
                                                 Commissioning tests

The following tests will be carried out on each installed cable length, after splicing and
termination to each WTG and ESP.

 Test Description                                         Particulars and      Test Circuit Description
                                                           Guarantees
 Conductors continuity                                        Record        All tests will be carried out from
                                                                            one cable end only
 Metallic screens continuity and check of                     Record
 grounding connections
 Identification of circuit phasing and circuit                Record
 continuity
 HVAC test for 24 hours                                       33 kV         Cables connected to the ESP
 (valid for all cable types)                                                transformer
 OTDR test on optical fibers                                                From both cable ends
 - at 1550 nm (dB/km)                                         ≤0.25
IV.   Technical
A.    34.5 kV Submarine Cable “A”

      1. Conductor

             Material/stranding type                     *    Cu       /       compacted         *

             Stranding per IEC or ASTM?                  *     IEC 60228, Class 2                *

             Size of conductor/number of strands         *       150         sq mm/              *

             Continuous current capacity at proposed     *                 400 (Note 1)          A
             configuration.

             Assumed thermal resistivity of seabed       *                   0.5           °K-m/W

             Assumed max temperature of seabed           * (6 ft burial depth on cable top) 19 °C

             Other factors limiting ampacity             *                         -              *

                                                         *                         -              *

             Maximum conductor temperature:

                Normal operating condition               *                     90                °C

                Emergency operating condition/duration   *                     105               °C

                Short circuit condition                  *                     250               °C

             Allowable short circuit/duration            *   31.7 kA rms sym           /   500   ms
             (80-250 °C)

      2. Conductor Shielding

             Type of Shielding                           *             s.c. XLPE                     *

             Thickness          (min. spot)              *                    0.41               mm

      3. Insulation

             Type of insulation                          *                    XLPE                *

             Thickness          (min. average)           *                    8.76               mm

      4. Insulation Shielding

             Type of Shielding                           *                 s.c. XLPE                 *

             Thickness          (min. spot)              *                     0.81              mm
5. Metallic Shielding (other than lead alloy)

        Material and Type                       *     Copper wire screen                 *
        Thickness                               *          0.8-0.9                      mm

        Allowable short circuit/duration        *     5.2       kA rms sym/ 500          ms
        (one screen, 25 mm2 sized, 65-170 °C)

        Type of grounding                       *               both ends                 *

6. Lead Alloy Sheath

        Thickness       (min. average)          *                     N/A                mil

        Allowable short circuit/duration        *                                         ms

        Type of grounding                       *                                          *

7. Steel Wire Armor

        Number of layers                        *                     One                  *

        Number and diameter of wires            *    58±2         /              5      mm

        Bedding material                        *          PP strings or fiber tape       *

        Allowable short circuit/duration        *   > 40       kA rms sym/ 500           ms

        Type of grounding                       *               both ends                 *

8. Outer serving

        Material                                *               PP strings                *
        Number of layers                        *               One or two                *

        Thickness       (indicative)            *                     3.5- 4.0           mm

9.      Electrical Characteristics

        Rated voltage (phase-to-phase)          *                  33                 kV rms

        Maximum working voltage (ph-to-ph)      *                  36.3               kV rms

        Basic Impulse Insulation Level (BIL)    *                     200                kV

        DC Resistance of Conductor at 20°C      *                  0.124             ohm/km

        AC Resistance of Conductor at 60 Hz     *                  0.159             ohm/km
        and 90°C

        Per Phase Inductance at proposed        *                 0.415              mH/km
        configuration
       Per Phase Capacitance at proposed               *               0.17            uF/km
       configuration

       Per Phase Charging Current at proposed          *               1.22              A/km
       Configuration at 33/1.732 kV

       Positive Sequence Resistance at 20 °C           *              0.170           ohm/km

       Positive Sequence Reactance at                  *              0.155           ohm/km
       proposed configuration

       Zero Sequence Resistance at 20 °C               *              0.380           ohm/km

       Zero Sequence Reactance at                      *              0.190           ohm/km
       proposed configuration

       Three-Phase Losses at 33 kV & maximum ampacity (400 A) (Note 2)

               ?   Dielectric Losses                   *              0.08             kW/km
               ?   Conductor Losses                    *              73.0             kW/km
               ?   Screen Losses                       *               3.5             kW/km
               ?   Armor Losses                        *               9.7             kW/km

10. Physical Characteristics

       Overall Diameter                                *               115±1                 mm

       Minimum Bending Radius                          *                1.7                  m

       Weight per meter of finished cable              *               21.5±1            kg/m

       Total length of this cable to be installed      *                 80                  km

       Maximum delivery length                         *                                     m

       Minimum length of spare cable                   *                 1000                m

       Bidder to confirm no factory or field splices   * Confirmed (unless factory damage) *

       Method of marking cable                         * Double color pattern for serving plus*
                                                       Numbered or colored tapes every 100 m
11.    Overall performance of 33 kV Cable “A”
       in proposed configuration with each WTG
       producing 70 A at 33 kV –10%

       Total 3-Phase Losses in Cable “A”               Please refer to paragraph 7 “Cables
                                                       rated power and losses”
               ?   Dielectric Losses                   *                                     kW
               ?   Conductor Losses                    *                                     kW
               ?   Sheath Losses                       *                                     kW
               ?   Armor Losses                        *                                     kW
      Percent voltage drop between most remote
      WTG and the ESP                                  *                                     %

      Serviceable life of cable & associated
      Terminations                                     *                   40             years

Note 1:      Maximum rating at 90 °C with cable installed in vertical J-tube (280/300 mm)
             with 28°C ambient temperature.
             Cables protected from direct solar exposure.

Note 2:      Referred to cable buried in seabed at 6 ft burial depth (on top of the cables), 19
             °C ambient temperature and 0.5 Kxm/W soil thermal resistivity.
B.   34.5 kV Submarine Cable “B”

     1. Conductor

            Material/stranding type                     *    Cu       /       compacted       *

            Stranding per IEC or ASTM?                  *     IEC 60228, Class 2              *

            Size of conductor/number of strands         *       400         sq mm/            *

            Continuous current capacity at proposed     *                 610 (Note 1)        A
            configuration.

            Assumed thermal resistivity of seabed       *                   0.5           °K-m/W

            Assumed max temperature of seabed           * (6 ft burial depth on cable top) 19 °C

            Other factors limiting ampacity             *                         -            *

                                                        *                         -            *

            Maximum conductor temperature:

               Normal operating condition               *                     90              °C

               Emergency operating condition/duration   *                     105             °C

               Short circuit condition                  *                     250             °C

            Allowable short circuit/duration            *   >40    kA rms sym         / 500   ms
            (80-250 °C)

     2. Conductor Shielding

            Type of Shielding                           *             s.c. XLPE                   *

            Thickness          (min. spot)              *                    0.51             mm

     3. Insulation

            Type of insulation                          *                    XLPE                 *

            Thickness          (min. average)           *                    8.76             mm

     4. Insulation Shielding

            Type of Shielding                           *                 s.c. XLPE               *

            Thickness          (min. spot)              *                     1.02            mm
5. Metallic Shielding (other than lead alloy)

        Material and Type                       *     Copper wire screen                 *
        Thickness                               *          0.8-0.9                      mm

        Allowable short circuit/duration        *     7.4       kA rms sym/ 500          ms
        (one screen, 35 mm2 sized, 65-170 °C)

        Type of grounding                       *               both ends                 *

6. Lead Alloy Sheath

        Thickness       (min. average)          *                     N/A                mil

        Allowable short circuit/duration        *                                         ms

        Type of grounding                       *                                          *

7. Steel Wire Armor

        Number of layers                        *                     One                  *

        Number and diameter of wires            *    68±2         /              5      mm

        Bedding material                        *          PP strings or fiber tape       *

        Allowable short circuit/duration        *   > 40       kA rms sym/ 500           ms

        Type of grounding                       *               both ends                 *

8. Outer serving

        Material                                *               PP strings                *
        Number of layers                        *               One or two                *

        Thickness       (indicative)            *                     3.5- 4.0           mm

10.     Electrical Characteristics

        Rated voltage (phase-to-phase)          *                  33                 kV rms

        Maximum working voltage (ph-to-ph)      *                  36.3               kV rms

        Basic Impulse Insulation Level (BIL)    *                     200                kV

        DC Resistance of Conductor at 20°C      *                  0.047             ohm/km

        AC Resistance of Conductor at 60 Hz     *                  0.063             ohm/km
        and 90°C

        Per Phase Inductance at proposed        *                 0.356              mH/km
        configuration
       Per Phase Capacitance at proposed               *               0.25            uF/km
       configuration

       Per Phase Charging Current at proposed          *               1.80              A/km
       Configuration at 33/1.732 kV

       Positive Sequence Resistance at 20 °C           *              0.100           ohm/km

       Positive Sequence Reactance at                  *              0.135           ohm/km
       proposed configuration

       Zero Sequence Resistance at 20 °C               *              0.250           ohm/km

       Zero Sequence Reactance at                      *              0.165           ohm/km
       proposed configuration

       Three-Phase Losses at 33 kV & maximum ampacity (610 A) (Note 2)

               ?   Dielectric Losses                   *              0.10             kW/km
               ?   Conductor Losses                    *              67.5             kW/km
               ?   Screen Losses                       *               10.4            kW/km
               ?   Armor Losses                        *               23.1            kW/km

10. Physical Characteristics

       Overall Diameter                                *               136±1                 mm

       Minimum Bending Radius                          *                2.0                  m

       Weight per meter of finished cable              *               31±1            kg/m

       Total length of this cable to be installed      *                 21                  km

       Maximum delivery length                         *                                     m

       Minimum length of spare cable                   *                 1000                m

       Bidder to confirm no factory or field splices   * Confirmed (unless factory damage) *

       Method of marking cable                         * Double color pattern for serving plus*
                                                       Numbered or colored tapes every 100 m
11.    Overall performance of 33 kV Cable “B”
       in proposed configuration with each WTG
       producing 70 A at 33 kV –10%

       Total 3-Phase Losses in Cable “B”               Please refer to paragraph 7 “Cables
                                                       rated power and losses”
               ?   Dielectric Losses                   *                                     kW
               ?   Conductor Losses                    *                                     kW
               ?   Sheath Losses                       *                                     kW
               ?   Armor Losses                        *                                     kW

       Percent voltage drop between most remote
      WTG and the ESP                                  *                                     %

      Serviceable life of cable & associated
      Terminations                                     *                   40             years

Note 1:      Maximum rating at 90 °C with cable installed in vertical J-tube (280/300 mm)
             with 28°C ambient temperature.
             Cables protected from direct solar exposure.

Note 2:      Referred to cable buried in seabed at 6 ft burial depth (on top of the cables), 19
             °C ambient temperature and 0.5 Kxm/W soil thermal resistivity.
C.   34.5 kV Submarine Cable “C”

     1. Conductor

            Material/stranding type                     *    Cu       /       compacted       *

            Stranding per IEC or ASTM?                  *     IEC 60228, Class 2              *

            Size of conductor/number of strands         *       630         sq mm/            *

            Continuous current capacity at proposed     *                 725 (Note 1)        A
            configuration.

            Assumed thermal resistivity of seabed       *                   0.5           °K-m/W

            Assumed max temperature of seabed           * (6 ft burial depth on cable top) 19 °C

            Other factors limiting ampacity             *                         -            *

                                                        *                         -            *

            Maximum conductor temperature:

               Normal operating condition               *                     90              °C

               Emergency operating condition/duration   *                     105             °C

               Short circuit condition                  *                     250             °C

            Allowable short circuit/duration            *   >40    kA rms sym         / 500   ms
            (80-250 °C)

     2. Conductor Shielding

            Type of Shielding                           *             s.c. XLPE                   *

            Thickness          (min. spot)              *                    0.61             mm

     3. Insulation

            Type of insulation                          *                    XLPE              *

            Thickness          (min. average)           *                    8.76             mm

     4. Insulation Shielding

            Type of Shielding                           *                 s.c. XLPE               *

            Thickness          (min. spot)              *                     1.02            mm
5. Metallic Shielding (other than lead alloy)

        Material and Type                       *     Copper wire screen                 *
        Thickness                               *          0.8-0.9                      mm

        Allowable short circuit/duration        *     7.4       kA rms sym/ 500          ms
        (one screen, 35 mm2 sized, 65-170 °C)

        Type of grounding                       *               both ends                 *

6. Lead Alloy Sheath

        Thickness       (min. average)          *                     N/A                mil

        Allowable short circuit/duration        *                                         ms

        Type of grounding                       *                                          *

7. Steel Wire Armor

        Number of layers                        *                     One                  *

        Number and diameter of wires            *    78±2         /              5      mm

        Bedding material                        *          PP strings or fiber tape       *

        Allowable short circuit/duration        *   > 40       kA rms sym/ 500           ms

        Type of grounding                       *               both ends                 *

8. Outer serving

        Material                                *               PP strings                *
        Number of layers                        *               One or two                *

        Thickness       (indicative)            *                     3.5- 4.0           mm

11.     Electrical Characteristics

        Rated voltage (phase-to-phase)          *                  33                 kV rms

        Maximum working voltage (ph-to-ph)      *                  36.3               kV rms

        Basic Impulse Insulation Level (BIL)    *                     200                kV

        DC Resistance of Conductor at 20°C      *                  0.0283            ohm/km

        AC Resistance of Conductor at 60 Hz     *                  0.042             ohm/km
        and 90°C

        Per Phase Inductance at proposed        *                  0.33               mH/km
        configuration
       Per Phase Capacitance at proposed               *               0.30            uF/km
       configuration

       Per Phase Charging Current at proposed          *               2.15              A/km
       Configuration at 33/1.732 kV

       Positive Sequence Resistance at 20 °C           *              0.082           ohm/km

       Positive Sequence Reactance at                  *              0.124           ohm/km
       proposed configuration

       Zero Sequence Resistance at 20 °C               *              0.220           ohm/km

       Zero Sequence Reactance at                      *              0.155           ohm/km
       proposed configuration

       Three-Phase Losses at 33 kV & maximum ampacity (725 A) (Note 2)

               ?   Dielectric Losses                   *              0.13             kW/km
               ?   Conductor Losses                    *              63.0             kW/km
               ?   Screen Losses                       *               14.0            kW/km
               ?   Armor Losses                        *               32.5            kW/km

10. Physical Characteristics

       Overall Diameter                                *               151±1                 mm

       Minimum Bending Radius                          *                2.2                  m

       Weight per meter of finished cable              *               41±1              kg/m

       Total length of this cable to be installed      *                 26                  km

       Maximum delivery length                         *                                     m

       Minimum length of spare cable                   *                 1000                m

       Bidder to confirm no factory or field splices   * Confirmed (unless factory damage) *

       Method of marking cable                         * Double color pattern for serving plus*
                                                       Numbered or colored tapes every 100 m
11.    Overall performance of 33 kV Cable “C”
       in proposed configuration with each WTG
       producing 70 A at 33 kV –10%

       Total 3-Phase Losses in Cable “C”               Please refer to paragraph 7 “Cables
                                                       rated power and losses”
               ?   Dielectric Losses                   *                                     kW
               ?   Conductor Losses                    *                                     kW
               ?   Sheath Losses                       *                                     kW
               ?   Armor Losses                        *                                     kW

       Percent voltage drop between most remote
      WTG and the ESP                                  *                                     %

      Serviceable life of cable & associated
      Terminations                                     *                   40             years

Note 1:      Maximum rating at 90 °C with cable installed in vertical J-tube (280/300 mm)
             with 28°C ambient temperature.
             Cables protected from direct solar exposure.

Note 2:      Referred to cable buried in seabed at 6 ft burial depth (on top of the cables), 19
             °C ambient temperature and 0.5 Kxm/W soil thermal resistivity.
7. CABLES RATED POWER AND LOSSES


The following table summarizes the rating power and losses, referred to the three-phase circuit, for each wind park section as proposed in the above layout
drawing.

                                                                    33 kV 3x150 mm2
         WTG                Rated current 1   Conductor temperature      Dielectric            Conductor               Screen                Armor
                                                                          Losses                Losses                 Losses                Losses
                                  (A)                 (°C)               (kW/km)               (kW/km)                (kW/km)               (kW/km)
           1                       70                 20.5                 0.06                   1.8                   0.1                   0.3
           2                      140                 25.0                 0.06                   7.5                   0.5                   1.2
           3                      210                 32.8                 0.06                  17.4                   1.1                   2.7
           4                      280                 44.5                 0.06                  32.3                   1.8                   4.7
           5                      350                 60.5                 0.06                  53.3                   2.7                   7.4
                                                                    33 kV 3x400 mm2
           6                      420                 43.5                 0.08                   29.2                   5.3                   10.8
           7                      490                 52.8                 0.08                   40.9                   7.1                   14.8
           8                      560                 64.2                 0.08                   55.3                   8.9                   19.4
                                                                    33 kV 3x630 mm2
            9                     630                 59.0                 0.10                   46.0                  11.0                   24.3
           10                     700                 68.9                 0.10                   58.0                  13.2                   30.3




1
    Generating voltage 33 kV -10% = 29.7 kV

				
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