Research On Generator Coherency And Substitution Of Generator Model Based On Measured Trajectory

Power system dynamic simulation is an essential way to investigate power system dynamic process, the validity of simulation is determined by the accuracy of system model and parameters. Synchronous motor ,whose models and parameters are very complicated, plays an important part in power system. And different models and parameters influence the dynamic behavior in power system differently. Therefore it is very necessary to analysis the effectiveness of synchronization generator models and parameters based on measured trajectory. This paper mainly researched on generator coherency and substitution of generator model .On the one hand, the simulation trajectory's error precision coming from different models is different from the measured trajectory. On the other hand, the number of low order model control parameter is less than that of high order. In the condition of accepted error precision,the selection of low order model can greatly help the correction of parameters. This paper proposed the error index system of trajectory between simulated and measured. On the basis, correct parameters using the method of trajectory sensitivity and analysis the substitution effect different generator model. The effectiveness and practicality of the model are validated by the means of an example researching on simulation data on the basis of different models and measured data, which come from three-phase short circuit testing on bis-machine infinite bus.The number of generators and parameters is great for a large power grid. How to research on these parameters influencing many trajectories is a premise that we can find much accurate parameters which guarantee the simulation trajectory approach to measured trajectory. There exists homology phenomenon in power system when subjected to disturbance. That is to say existing consistency or similarity on dynamic characteristics for each generator set. Therefore, this paper studies on generator group according to disturbed trajectories. The purpose is to research on parameters influencing each generator trajectory turning to each trajectory group. Thus not only that simplifies the correction of parameters but also its physical concept is clear.