MODELLING, IDENTIFICATION AND OPTIMAL CONTROL OF HYDROGOVERNOR SYSTEMS.

Modelling and identification are essential prerequisites for the control of any process. In power systems, the transfer functions of various units that relate outputs with inputs need continuous evaluation with the changing conditions of load and generation pattern, for optimum dynamic performance. Further, reduced order models consistent with the performance of the system are required to replace higher order systems in dynamic studies like load frequency control. In this paper, a hydro speed governing system is considered for model reduction and its equivalent first order model is identified using gradient techiques. The effect of varying load conditions on the model parameter is investigated and the results are presented. The validity of such a simplified model is established for the case of the optimal load frequency control, for a single area hydro system.