Tender Document Volume - 2 - BPDB

a. Temperature detector (Refer to Clause 4.1.10)
- normal use :more than 6 (six)
-Spare
:more than three(3)
b. Thermometers and thermocouples at bearing drain of generator and
exciter bearings, and at any other location required for operation monitor.
c. Pressure gauge at bearing oil feed, and at any other location required
for operation.
d. Alarm contacts
e. Spare heater
The stator shall be equipped with space heater. During the generator stop, the
space heater shall be in service automatically.
f. Other
Other instrument, terminal box, hardware buried into the generator foundation
and all other necessary accessories for generator.
4.2 Exciter And Automatic Voltage Regulator
4.2.1 Exciter
A complete voltage regulating and excitation system shall be provided. A complete
and details description of the proposed system that meets the requirements of
these specification shall be submitted with the Tender.
A shaft mounted brushless type with static type control shall be provided.
The excitation system shall match the generator rating and shall maintain the
voltage of the unit within a tolerance of plus and minus 0.5% of rated voltage
regulation. The exciter shall have capacity to supply not less than 110% of the
field current required by the generator at rated output, power factor, frequency
and voltage.
The rated voltage of the exciter shall be 110% of the machine excitation voltage
at the rated output of the machine.
The ceiling voltage of the exciter shall not be less than 140% of the matching
excitation voltage. Insulation of stator and rotor winding of the exciter shall be
class F. A field breaker and discharge resistance shall be provided or alternatively
special provisions must be taken to either discharge or suppress excitation
following generator fault.
The excitation system shall have ample capacity to permit operation throughout
its capability up to over-excitation and under-excitation limit as shown in the
manufacturer's capability curves.
Over excitation limiter and under excitation limiter shall be provided.
Ghorasal 200 MW to 300 MW Gas Turbine Peaking Power Plant Project (Vol-2 of 3)
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