| Transient simulation of the distributed energy resources powered micro-grid is the foundation to understand the fast dynamic characteristics and to reveal the various related transient problems in the system. The implementation of transient simulation is considered to be of great scientific and engineering significance. The models suitable for the transient simulation are studied. The algorithms for detailed transient simulation are studied repectively from modeling capability, accuracy improvement and simulation efficiency Nodal analysis based electromagnetic simulation methodology is employed to design the transient simulation program - TSDG. The work in this dissertation is summarized as follows:1) According to the modeling requirement of the transient simulation, methods to extend modeling capability of electrical system and control system are studied. Modified augmented nodal analysis is used to extend modeling capability of electrical system. Automatic differentiation is adopted to realize the modeling of static nonlinear element in control system, especially for complex nonlinear characteristics dominated DG and energy storage elements. Case studies show that TSDG provides sufficient low-level modeling capability, it can totally meet the requirement of the transient simulation.2) Algorithms on improving simulation accuracy are studied as well. Newton method is applied on obtaining precise solution of control system. An interpolation scheme of electrical system is presented for power electronic circuit simulation. Case studies show that TSDG is with highly accuracy and well numerical stability as the algorithms adopted.3) Methods for accelerating transient simulation are studied. Pseudo Newton method is applied on accelerating the speed of control system solving. A parallel solving strategy of electrical system and control system is proposed with the merit of easy-realization. An improved parallel solving strategy is presented to enhance the accuracy of the former algorithm. With the characteristics of naturally decoupling of DGs and its controller, a parallel solving strategy for control system is presented. Case studies show that the parallel version of TSDG can achieve at most two times faster than the series one in some cases as the algorithms adopted. 4) Transient simulation of typical DG systems, including PV generation system, fuel cell generation system and micro-turbine generation system, are realized with proper control strategies. Mostly encountered large signal disturbances are considered in the cases. Transient simulation of European LV micro-grid with multiple DGs is accomplished to validate the effectiveness of the methods presented. For all the cases, the results of TSDG are compared with that obtained from various electromagnetic transient simulation tools.
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