Transient stability calculation of multi-machine system taking into account the detailed model of hydraulic system

hydraulic systems;  model;  Multi-machine system;  Transient stable

The simplification of hydraulic system model is one of the main reasons restricting the improvement of the simulation quality of transient process of power system. Different forms of mathematical models of complex hydraulic systems for transient stability analysis of power systems are established, including rigid hammer models and elastic hammer models of water diversion systems, and linearization models and nonlinear models of hydro turbines. By calculating the transition process of multi-machine system with complex hydraulic system under large disturbance, the influence of different models of water diversion system and turbine on the transient stability calculation results is analyzed. The results show that different models of hydraulic system have little influence on the initial stage of transient stability calculation of multi-machine system. The rigid hammer model is close to the change curve under the elastic hammer model. The change curves under the nonlinear turbine model and the linear turbine model are quite different in the later stage of the transient process. The simplified model is too simple, and the calculation result error is large.