METHOD FOR HEAT RATE IMPROVEMENT IN PARTIAL-ARC STEAM TURBINE

摘要

Method for improving the heat rate of a steam turbine operated in a partial-arc mode includes sequential closing of control valves to establish a first arc of admission followed by a reduction of steam pressure to a predetermined level. Additional valves are closed to bring the admission arc to an optimum value and power reduction is thereafter affected by pressure reduction. In a further method, low power operation is achieved by reducing the arc of admission below optimum when steam pressure has been reduced to a minimum value.