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Distributed generators systems and Microgrid are becoming more important to increase the renewable energy penetration in the public utility. This paper presents a mathematical model for connected inverters in Microgrid systems with large range variations in operating conditions. No-lineal tools and computer simulations, phase-plane trajectory analysis, method of Lyapunov and bifurcations analysis for evaluate the limits of the small signal models are used, and conclusion suggested utilizing models that can permit to analysis of the system when subjected to a severe transient disturbance such as loss a large load or loss of generation. The study of transient stability for Microgrid systems in stand-alone of the utility grid is useful to improve the design of Microgrid's architecture.
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... The dynamic response of different DGs during large disturbances , characteristics of DG fault current contribution with different control strategies [54][55][56][57], and transient process simulations of grid connected Microgrid [61][62][63][64][65][66][67][68][69][70] are mainly discussed. And the transient stability analysis of islanded Microgrid was shown in [71][72][73][74][75][76][77][78][79][80][81][82][83][84]. ...
... Thus the transient behaviors of islanded Microgrid to large disturbance are much sensitive to that of the grid connected Microgrid. More and more researches have been focused on this field [71][72][73][74][75][76][77][78][79][80][81][82][83][84]. ...
... The transient stability of Microgrid is closely related to the load characteristics. Most of the researches focused on the RCL load, even though the transient behaviors of the motor load, the active load are used more widely [77,78]. A transient stability model based on controlled current source was proposed in [78]. ...
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