A Simplified Hybrid Approach to Dynamic Model a Real HRSG

This paper proposes a dynamic simplified approach to model a Heat Recovery Steam Generator of a Gas Turbine Combined Cycle (GTCC) and its validation against field data. The adopted framework begins with some physical considerations on global HRSG structure, and then focuses on a specific application for a real plant, i.e. a 390 MW multi-shaft combined cycle based on the AEN94.3 A4 frame. Moreover the model embodies some parameters, which are easily derived from historical data to enhance the forecasting capabilities of the software, resulting in a hybrid model which covers a high range of working conditions. The whole model is designed to run in Excel/Visual Basic environment to allow for extended use by people who have limited experience in advanced modelling software. The model so created has been handled through a training process based on 10 days of experimental data, in order to create the basis for true system flexibility. Therefore, the feasibility of this approach has been verified using a Gas Turbine (GT) load profile accomplished in everyday working operations and validating the results against field data.Copyright © 2015 by ASME