A new voltage source converter-HVDC transmission system based on an inductive filtering method

Different from the existing voltage source converter (VSC)-based high voltage direct current (HVDC) transmission system, this article proposes a new voltage source inductive filtering converter (VSIFC)-based HVDC transmission system. It uses the inductive filtering transformer and the related full-tuned branches to replace the commutating reactor and/or transformer and the high-pass damping filters, which makes the VSIFC-HVDC with more obvious characteristics on integrated design and installation. This article concerns on the converter operating characteristics of the VSIFC-HVDC system, which include harmonic suppression in the AC valve winding of the transformer, and the active and the reactive power (P and Q) operating ability of the VSIFC. The equivalent circuit model and the mathematical model of the VSIFC are established. Based on this, the theoretical analysis is performed. Then, within the PSCAD/EMTDC environment, the filtering and the P and Q characteristics of the new VSIFC and the traditional VSC-based HVDC transmission systems are simulated, respectively. By comparison, it validates the theoretical analysis, and shows that the VSIFC-HVDC not only reduces the polluted area of the harmonic, but also has the better transmitted power ability and the wider reactive power control range.