Structure-Preservation Model Aggregation for Two-Stage Inverters Based Large-Scale Photovoltaic System

Abstract

With the increasing penetration level of large-scale photovoltaic (PV) generator connected to the grid, an accurate simulation model is required for the dynamic analysis of the PV system. However, the detailed electromagnetic simulation of the large-scale system is complex and the dynamic response capability is estimated with obstacle caused by large computational burdens. Therefore, a precise dynamic aggregated model is indispensable for the displacement of the large-scale PV system. The structurepreservation based aggregated model with comprehensive equivalent parameters for large-scale PV system is proposed in this paper. A complete two-stage PV system model is established to analyze the dynamics of the system. Then, the aggregation method is obtained by comparing the dynamic equations of the detailed model with the aggregated model, which is based on the energy relationship in the PV system. Furthermore, four different case studies are considered including the aggregation of identical and different ten parallelconnected PV units both under the same irradiance condition, and the aggregation of different ten parallelconnected PV units under different irradiance and weak grid scenarios, where the aggregation models are obtained through the proposed equivalent modeling method. Finally, the effectiveness of the proposed aggregation method is verified by the simulation results from PSCAD/EMTDC platform, and the consistency between the aggregated model and the detailed model is confirmed under different disturbances of irradiance variation, and continuous symmetric and asymmetric grid faults.

Application of Particle Swarm Algorithm in Nanoscale Damage Detection and Identification of Steel Structure

“…Kortenbruck et al for the first time, based on the numerical simulation of beam structures damage identification was carried out according to the change of flexibility before and after damage [ 6 ]. Han et al studied the damage identification problem in the background of the numerical simulation of the girder bridge structure, and achieved good results, mainly using the weighted modal flexibility method [ 7 ]. Murshid and Singh studiedthe effectiveness of the structural damage localization method based on the difference of compliance curvature matrix was verified by numerical simulation of beam-like structures [ 8 ].…”