In Reply to: Re: Variable pressure operation posted by Anthony Salvarezza on 05/11/00 at 10:10 AM:
I realize this may be a little late, but I just stumbled on this website recently.
Not to disagree with the previous response, but one benefit of variable pressure control is the reduction of throttling loss.
If you can keep your turbine valves more open, you reduce the throttle loss across these vavles, and bring up total efficiency.
Typically you would have a curve of pressure that the boiler would maintain to match a MW output.
The problem is that this is not very responsive, so during load ramps you may want your throttle valves to control to a pressure setpoint. But at a steady load this will give you a thermodynamic improvement.
Hope this is useful.