The Mid-long Term Dynamic Simulation Of Power System Based On PSD-FDS

Large-Scale Interconnected Power System is an extreme complex nonlinear system, its problems related to the stability are increasingly complicated, which shows varied forms. With the growing scale and complexity of power system, not only the transient stability of the power system should be concerned after subjected to a large disturbance, but also the mid-long term voltage stabilization should get more attention. In this thesis, considering the detailed dynamic models of mid-long term processes, many researches about power system stability have been done based on Full Dynamic Simulation (PSD-FDS). According to the construction of Yunnan Power Grid in2015, this thesis analysed mid-long term voltage stabilization in large-scale power system.Combining with the nationwide AC-DC interconnected power system in China, this thesis described the Large-Scale Interconnected Power System characteristics and the problems. The new mixed integral algorithm and the characteristics of Full Dynamic Simulation (PSD-FDS) software are introduced, and its typical mid-long term dynamic models. In Chapter III, analyze the mid-long term dynamic models which affect the power system stabilization by simulation, including boiler and its control system;automatic generation control (AGC); over excitation limiter (OXL) and on-load tap changer (OLTC). This thesis analyzed how the OLTC affect the system mid-long term voltage stabilization undering different load recovery characteristic and different action, respectively.In Chapter IV, the data of Yunnan Power Grid in2015is established which including the necessary mid-long term dynamic models, analyze the stabilization of this practical power system, especially its mid-long term voltage stabilization. For some disturbances, the system may not face any transient instability problem in short-term but may suffer from voltage instability problem in mid-long term because of the OXL and OLTC. Boiler and induction motor loads are important factors for accurately modeling the power grid system.