Entergy Independence Nox/Heat Rate Optimizationand Steam Temperature Control with NeuralNet/Model Predictive Control Combo

摘要

Entergy Independence Units 1 & 2 are twin furnace 800 MW PRB coal fired drum units constructedrnin the early 80’s. The plants were recently retrofitted with a modern DCS and achieved significantrnperformance improvement. To further the performance benefits an optimization system includingrnmulti-variable dynamic control was added to the plant DCS. The system combined Neural Nets andrnexpert systems with Model Predictive Control to achieve effective non-linear optimization and robustrndynamic control. The Neural Nets portion addressed the Nox issue to handle the strong non-linearitiesrnand maximize reductions. The Model Predictive Control portion tackled the dynamic control of steamrntemperatures, O2, and other variables to minimize heat rate while providing tighter control of peakrntemperature during dispatch. An expert system based smart soot blow portion completed thernoptimization system. Nox benefits exceeded 20% reduction. Heat rate benefits provided a projectrnpayback in a matter of months and were quantified applying the Delta Heat Rate Methodology. Steamrntemperature peaks were trimmed to enhance dispatch capability.