Classical/Advanced controls for hydraulic power plants

Abstract

This paper presents control problem of hydraulic plants. The renovation of the control in hydraulic power plants in France and consultant engineering for new hydraulic plants in foreign countries motivate to examine what is the actual control in these plants and what possibilities of improvement exists with the modern advanced approaches. The need for adequate models is a long standing one. There exists since a long time nonlinear partial derivative models of hydraulic plants which have been carefully experienced. The first approach to have a simplified model was to identify simulated responses of the complicate model. Indeed, this approach was not fully successful. Some dynamical long term effects cannot be identify by this way due to nonlinear effects. Another approach using physical nonlinear differential models was completely successful by representing these long term effects. Linearized state space models were deduced which allow to study carefully classical and modern approaches. It was found that classical approach may be greatly improved by precompensator feedback assuring positivity. LQG control using all measurements available was particularly efficient and gives good hopes that practical experiments will be successful.