Research On Decoupling Simulation Of Power System Dynamics

Power system dynamic simulation is not only the basic tool for the analysis and control of power system dynamic security, but also the key foundation for establishing the system operation modes in the power grid dispatching center. Numerous faults and tests show that simulation can not reproduce the true dynamic behavior of power system, it is generally believed that inaccuracy models and parameters lead to the deviation between result of simulation and true dynamic behavior. Consequently, how to correct the erroneous models and parameters to improve the validity of dynamic simulation needs urgently to be resolved.The component of power system is numerous and tight coupled. So it is difficult to verify the validity of simulation and recognize the erroneous models and parameters. We can use hybrid dynamic simulation to solve this problem by injecting measured data into simulation.In this paper, a new decoupling method is proposed based on the Thevenin equivalent. The method decouples the system by converting the complex external system into a simple Thevenin equivalent. Case study illustrates the effectiveness of the proposed method.A verification method is proposed based on decoupling simulation, it can be used in simulation verification and error tracing. A network partition method is proposed based on spur track density. An error source recognition method based on trajectory sensitivity analysis is presented. Case study of a two machine and an infinite bus system in dynamic laboratory validation shows that the verification method of decoupling simulation is valid.