2. Turbine and Generator
For Waste heat recovery-based power plant the condensing type steam turbine
of single/dual pressure, multi-stage, impulse single cylinder turbine is envisaged.
The turbine would be designed for inlet steam parameters according to the
steam parameters at the outlet of waste heat recovery boilers and considering the
pressure drop and with an exhaust pressure of 0.116 Kg/cm2(a).
A fully automatic gland sealing system shall be provided for turbine unit, which would
have provision for receiving sealing steam from auxiliary steam header during start-
up and low load operation.
The turbine generator will be equipped with Woodward 505 electronic governing
system ensuring stable operation during grid frequency fluctuation and load throw-
off condition. Turbine generator would be equipped with turning gear.
The turbine construction of LP blades shall ensure safe and stable operation of TG
set when condenser flow reduces to a minimum, corresponding to minimum cooling
steam flow through the turbine.
The generators would be 3 phase, Water cooled machine preferably directly coupled
to the steam turbine and would have a nominal rating as per turbine capacity.
Generator shall be designed at 0.8 power factor (at generator terminal) and for the
single extraction condensing TG sets. The generators would deliver power at 11 kV
±10%, 3 phase, 50 Hz +3% / - 5%.
The generator excitation system would be brush less type and capable of maintaining
steady generator terminal voltage under variable load conditions and also generator
stability under transient conditions. The excitation system would be complete with
dual, separate automatic voltage regulator and all necessary metering and supervisory
equipment. Generator output terminals will be connected to generator transformer
primary through segregated phase and neutral side bus ducts.
Typical LP Admission Turbine Cross-section: