Simulation Research On Excitation Control Law Based On Large Hydro-generator Including Magnetic Saturation

With the continuous development of power system, the new challenges have been brought into security and stability control by HV AC/DC power transmission, large capacity generators operation and national network. An important way to solve the problems is simulation research on power system dynamic characteristic accurately. According to the PARK equation, the subtopic of the "effect between generator magnetic saturation and excitation control law" is about two major tasks: the one is established one machine-infinite system under different magnetic saturation conditions. The other is, based on this model, compared different excitation control law when three phase sudden short circuit fault occurs. Therefore, it can provide an important mean of research to obtain effects between generator magnetic saturation and excitation control law. The main research results are as follows:1. In order to analyse the influence of generator magnetic saturation on the generator-grid transient process, one machine-infinite system is established. In this model, based on no-load characteristic of generator, a model of synchronous generator which is included magnetic saturation is presented.2. Based on transfer function of excitation system, the simulation model adopts power system stabilizer (PSS) which the rotation rate deviation△ω is used as input signal.3. Based on simulation of steady-state of grid connected, three phase sudden short circuit and fault cleaning, research on the effects between generator magnetic saturation and excitation control law under different operation conditions can be analysed in-depth.