Plant-wide physical model-based control for a thermal power plant

This paper reports the development of a constrained, nonlinear physical model-based, predictive control strategy for improved plant-wide control of a thermal power plant. The proposed strategy makes use of successive linearisation and extended Kalman filtering to obtain a linear state-space model. The linear model and a quadratic programming routine are then used to design a constrained long-range predictive control routine. The proposed approach places major emphasis on better disturbance modeling based on a physical plant model. The paper discusses how this approach results into selection of a specific set of model parameters for online estimation to account for time-varying system characteristics resulting from major system disturbances and ageing. A plant model with 14 nonlinear ODEs, simulating the dominant characteristics of a 200 MW oil-fired power plant at Ballylumford, N. Ireland, has been used to test the control strategy.