Comparison of different calculation methods for a power semiconductor based interphase power flow controller

In this paper a new dynamic interphase power flow controller (DIPFC) calculated in state space is described and compared with a fundamental-component based model. The analytic calculation in state space is based on a transformation into space-phasor and zero-sequence components. Accordingly the entire system is divided into orthogonal networks for each switching status. The resulting state-space descriptions can be coupled into a linear inhomogeneous boundary value problem utilizing the periodic switching sequence in steady-state. The solution can be transformed back into natural coordinates. Therefore the entire system and all time functions can be calculated analytically. Finally the analytic method is verified using a fundamental-component model calculating the fundamental impedance of the switched inductance by an evaluation of the Fourier coefficient integral.