Download SPECIFICATION FOR 132kV STATION CLASS SURGE

SPECIFICATION FOR 132kV STATION CLASS SURGE ARRESTERS
A.
SYSTEM INFORMATION
A-1
System Conditions
The networks are mainly of outdoor type. The basic parameters are set out below:
Nominal system voltage between phases
kV
132
Earthing of neutral at transformers
Solid
System earthing
Effectively earthed
System Frequency
Hz
50
System highest voltage
kV
145
Symmetrical short circuit current at rated voltage RMS
(ultimate)
kA
25/40
Impulse withstand voltage – Main Transformer
kV
550
Impulse withstand voltage – Other Equipment
kV
650
Power frequency voltage (1 min.)- Main Transformer
kV
230
Power frequency voltage (1 min.)- Other Equipment
kV
275
A-2
Minimum Substation Clearances
Air insulated outdoor and indoor busbars and
electrical clearances as listed in the following table: -
connections
shall
have
Highest system voltages between phases
kV
145
Minimum clearance between live metal and earth
mm
1350
Minimum clearance between live metal of different phases
mm
1350
Minimum safety clearance between the nearest point not at
earth potential of an insulator to ground (Pedestrian Access)
mm
2300
Minimum safety clearance between live metal and positions to
which access is permissible with other conductive equipment
mm
3650
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132kV L.A.
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A-3
Pollution levels of Insulators and Bushings
25 mm/kV (Pollution Class III)
A-4
Service Conditions
The following service conditions shall be taken into account in designing of material and
equipment.
B.
(a)
Altitude above sea level
< 1000 m
(b)
Max. ambient air temperature
40 °C
(c )
Max average daily temperature
30 °C
(d)
Lowest Ambient temperature
+5 °C
(e)
Max. Solar radiation
(f)
(g)
Mean monthly solar radiation
Max. Relative humidity ( 24 hrs)
(h)
(i)
Isokeraunic level
Mean wind velocity (24 hours)
60 -80 days/an
65 km/hours
(j)
Annual rainfall up to
5250 mm
(k)
(l)
System Highest voltage
System Earthing , 132kV
1000 W/m2
425 W/m2
90 %
145 kV {as applicable}
Direct
MINIMUM REQUIREMENTS FOR MANUFACTURERS
The bidder shall ensure, that each equipment offered , is manufactured by a
manufacturer with a minimum of ten (10) years successful experience in
manufacturing comparable equipment, in rated voltage and capacity, to the
equipment offered under the contract.
If the offered equipment is manufactured under license, the service experience of
equipment manufactured by the parent company shall not be counted as service
experience of the licensee equipment.
Bidder shall provide adequate evidence of compliance to above requirements to the
satisfaction of the C E B . Bids non-complying with above requirements or
with incomplete evidence of compliance would be rejected.
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132kV L.A.
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C.
TECHNICAL SPECIFICATIONS
C-1
The 132 kV station class Gapless Surge Arrestors (for outdoor use) shall be of
the metal oxide type using Zinc oxide resistor blocks of non linear characteristic
without air gap. They shall comply IEC 99-4 and shall be entirely suitable for
operation under the system conditions specified; including system voltage rises
on unloading long transmission lines and shall have sufficient capacity to
discharge system charging currents without damage.
C-2
It is expected to use these surge arrestors at the line end and near the HV power
transformers. The present surge arrestors have a center to center distance of 3m
in the switch yard and transformer bay. The surge arrestor shall be capable or
resealing against the maximum transient over voltage (TOV).
C-3
The surge arrestors shall be connected between each phase and earth in a threephase system.
C-4
The active element shall be housed in a gas tight insulator of polymer
compound. The creepage distance shall be minimum 25 mm/kV phase to phase
based on the rated voltage of the system.
C-5
The surge arrestors shall be equipped with a grading ring. If necessary, an
internal grading system may control the voltage distribution along the metal
oxide resistor stack.
C-6
A pressure relief device shall prevent damage by overpressure and discharge
counters shall be provided to indicate number of operations for each arrestor.
C-7
Surge arrestor shall be of heavy duty type. Connection to ground shall be by
copper cable via a surge counter. A suitable surge counter shall be provided
with the arrestor.
C-8
Surge arrestor shall withstand maximum local wind force and conductor forces.
The arrestors will be mounted vertical upright.
C-9
The quality of design and manufacturing process shall be assured in
accordance with the ISO 9000 series standards. Relevant ISO certificates shall
be furnished with the offer.
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132kV L.A.
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D.
APPLICABLE STANDARDS
The equipment and the components supplied shall generally be in accordance with the
standards specified below or later editions and/or amendments thereof:
D-1
D-2
D-3
IEC 99-4 Metal oxide surge arrestors without gaps for ac system.
ISO 9000 series for design, manufacture and quality control.
IEC 61166/IEE693 - Seismic acceleration withstand
E.
TERMINAL & NAME PLATE
E-1
Suitable terminals shall be provided to connect to the existing line. Existing
system has two wires of 30mm at each terminal end. Standard type of terminal
shall be offered.
E-2
All the rated data of the complete surge arrestor shall be given on the main
rating plate. The individual unit shall have individual rating plate with rated data
of that unit. The rating plate shall be attached to the surge arrestor base.
E-3
If the supplier is granted the offer, the General Arrangement Drawings including
nameplate drawing shall be produced for review, before starting the
manufacturing process.
F.
TESTS.
F-1
Type tests.
Following Type test reports of similar surge arrestors according to the
requirements set out by the latest edition of IEC recommendations 99-4 shall be
forwarded with the offer.
1.
2.
3.
4.
5.
6.
7.
8.
Insulation withstand test
Residual voltage test
Long duration current impulse withstand test
Operating duty test
Pressure relief test
Tests of arrestor disconnections
Artificial pollution test
Partial discharge test
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132kV L.A.
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9. Seal leakage test
10. Current distribution test for multi column arrestor
The type tests shall be carried out for a sample manufactured at the same workplace
where the offered equipments are manufactured. The type tests shall be carried out by
an independent and internationally recognized testing institute for HV equipments.
F-2
Routine Tests
In addition the manufactured arrestors shall be routine tested according to the
IEC standard 99-4 and shall be forwarded with the delivery.
All the test reports shall be in English.
G.
PACKING AND DELIVERY
G-1
Packing.
G-1-1 Precautions shall be taken to ensure that the equipment is safe for transportation
by sea.
G-1-2 Packing in cases shall be so carried out that there will be no movements of the
contents.
G-1-3 Each crate or package shall contain a packing list in a waterproof envelope and
copies in triplicate shall be forwarded to CEB prior to dispatch.
G-2
Delivery
Delivery period shall be approximately 16 weeks after opening the LC. Clearing
and transport to the site will be done by CEB.
H.
ERECTION AND MAINTENANCE.
H-1
Erection and Commissioning of the surge arrestors will be done by CEB staff.
H-2
A complete erection manual in English which shall comply with IEC/ IEEE
standard together with drawings of the complete surge arrestor and counters shall
be supplied. Any clarification that will be required during erection shall be
provided free of charge.
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132kV L.A.
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H-3
Complete erection, operation, maintenance and dismantling instructions including
mechanical drawings with details such as high voltage terminal drawings, earth
terminal details, details of the mounting plate, details of the name plate, bolt
torque, etc. shall be furnished with the offer.
H-4
The operating and maintenance manuals together with all relevant drawings and
circuit diagrams shall be supplied.
I.
VALUES AND DATA.
Attached as Annex A
J.
WARRANTY
Warranty period of at least 18 months after delivery or one year after commissioning
against design and manufacturing defects shall be applied for all the equipment supplied
under the Bid. Manufacturer/ supplier shall agree to supply such defective items or rectify
such defects free of charge during the warranty period.
CEYLON ELECTRICITY BOARD
GENERATION DIVISION
Generation Headquarters
New Kelani Bridge Road,
Kolonnawa.
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132kV L.A.
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Annex A
Pg 1
SCHEDULE OF GUARANTEED TECHNICAL PARTICULARS
1.
Manufacturer
:-
………………………….
2.
Type
:-
………………………….
3.
Country of origin
:-
………………………….
4.
Type tested yes/no
:-
Yes
5.
System earthing
:-
Direct Earthing
6.
System BIL
:-
650 kV
7.
Quantity
:-
40 nos (poles)
No.
DESCRIPTION
REQUIRED
1
Nominal system Voltage kV
132
2
Station class as per ANSI Yes / No
Yes
3
System Frequency
4
Type eg. Metal Oxide
5
Standards
6
Highest system voltage Um
kV
7
Cont. operating Voltage Uc
kV
8
Rated voltage Ur
kV
9
Long duration line discharge class
10 Nominal discharge current
11
OFFERED
50 Hz
MO
IEC 99-4
In
145
132/√3
2 or better
kA
Residual voltage on 8 /20 current impulse
(peak kV)
10
300-400
12 Equipped with counter
Yes/No
Yes
13 Creepage distance of insulator
kV/mm
25
14 Type of insulator
Polymer
15 Colour of the insulator
16
Leakage current through the coupled arrestor
at rated voltage mA
………………………
Authorised Signature
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132kV L.A.
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Annex A
Pg 2
No.
DESCRIPTION
REQUIRED
17
No. of units in complete assembly
18
Length of each unit
mm
19
Height of complete arrestor
mm
20
Weight of complete arrestor
kg
21
Grading rings
Yes/No
22
Pressure relief capability min.
23
Min. mechanical strength (Cantilever) Nm
24
Pressure relief class
25
26
27
Terminals to connect 30 mm two
conductors
Warranty as per Clause 24 of General
Conditions
Type test reports as per Technical
Specification Clause 6
……………………………..
Authorised Signature
OFFERED
Yes
kA
40
1600
A
Yes
Yes
Yes
Company Seal
Name of the Bidder
Date:- …………… 2011.
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132kV L.A.
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