Switching based modeling of grid interconnected hysteresis current controlled VSC converters

VSC based converters are among the most preferred interfaces to perform the interconnection, especially for integration of distributed energy sources, active filtering, and power supply applications. Hysteresis current control presents very attractive characteristics for these applications such as: robust control, fast dynamical response, built-in over-current protection and simple and reliable implementation. However, its highly nonlinear nature have been represented a challenge for the proposal of mathematical models to perform analysis and design tasks. This paper proposes a novel modeling approach based on the accurate calculation of the switching times for time and frequency analyses for grid interconnected hysteresis current controlled VSC converters. From this proposal, analytic formulations in the time domain and frequency domain of the harmonics generated by the controller are drawn. These can be useful to develop analysis and practical design methodologies based on numerical methods.