|
Power generation has become an increasingly competitive
arena. The cost of operating power plants comes mostly from
the fuel bill, which runs in the billions of dollars
annually. In order to minimise the fuel bill and maximise
pant efficiency, a plant’s load-following capability must be
optimized, that is, to follow the demand of power closely. A
great deal of attention must be given to the controller that
regulates water level (and steam pressure) at the
steam-generating unit “the boiler-drum”. The control
strategy is complicated by the non-linear and non-minimum
phase characteristics of the boiler-drum. This paper
illustrates our work in the optimization of load-following
scheme by applying a 3-element controller scheme to regulate
the boiler-drum’s water level. The controller is then
cascaded with another feedback loop that regulates steam
pressure. The results from the control scheme have shown
considerable improvement over a typical boiler-drum’s water
level control strategy.
Keywords:
Shrink-and-swell, control, boiler-drum’s, optimization,
boiler-drum. |
