Dynamic Modelling of AC Micro grids to transient stability analysis

Increasing the penetration level of distributed generation units as well as power electronic devices increases the complexity and variability of the dynamic behaviour of the micro grids. Micro grids have many challenges, such as being random in their production. As a results, the energy production from distributed generation sources will be constantly fluctuating. Therefore studying the micro grid transient modelling and its signal stability are importance. One of the major disadvantages of most studies on micro grid modelling is their excessive attention to the steady state period and the lack of attention to micro grid performance during the transient period. Also, in most of papers, the behaviour of different micro grid loads has not been studied. One of the mechanisms of power systems stability studies is the application of state space modelling. These stability studies including the development of state space models of various components of the power system and then linearizing them around an equilibrium point. In this paper, a comprehensive method for modelling of islanded inverter-based micro grids with dynamic and static loads is presented. The basic concepts of the proposed method are dq۰ transformation and dq۰-based models. In order to find a complete and accurate model of islanded inverter-based micro grid, the sub-modules of generation, network and load must be modelled in local dq reference and then transferred to a common reference. The simulation results show the effectiveness of the proposed modelling approach for transient stability studies.

کلیدواژه ها:

Micro grid ، Dynamic modelling ، transient state ، distributed generation ، state space