Patent ID: 8733104
Filing Date: 2014-05-27
Classification: F22G

Abstract:
1. A heat recovery steam generation system, comprising: at least one superheater in a steam path for receiving a steam flow and configured to produce a superheated steam flow; an inter-stage attemperator for injecting an attemperation fluid into the steam path; a control valve coupled to the inter-stage attemperator, the control valve configured to control flow of the attemperation fluid to the inter stage attemperator; and a controller comprising a feedforward controller configured to determine a desired amount of flow of the open loop attemperation fluid and a trimming feedback controller configured to compensate for inaccuracies in the determined amount of flow of the open loop attemperation fluid to determine a net desired amount of flow of attemperation fluid through the control valve into an inlet of the inter-stage attemperator based upon an outlet temperature of steam from the superheater; wherein the controller is further configured to: