The operational conditions at the Dalsfoss power station are complicated due to many requirements such as environmental regulations and safety constraints. Model predictive control (MPC) has been in use at this power station to control the floodgates at the Dalsfoss dam. However, the current formulation of MPC at the power plant does not have routines to explicitly handle output constraints. 

In this paper, a new improved optimal control problem (OCP) is formulated for the operation of the flood gates at the Dalsfoss power station. This new OCP formulation is thought to be relatively easier for the operators to understand and it is more flexible to the violation of constraints. The aim of this paper is to extend the current MPC used at the power plant so that the output constraints are systematically included in the new improved MPC formulation.  Two alternatives are presented and their robustness to an uncertain disturbance is analyzed through robustness analysis.