Topology and Control Strategy of PV MVDC Grid-Connected Converter with LVRT Capability

This paper proposes an isolated buck-boost topology and control strategy for the photovoltaic (PV) medium-voltage DC (MVDC) converter with low-voltage ride through (LVRT) capability. The proposed operates on either boost or buck mode by only controlling active semiconductors side. Based this topology, (MV) dc–dc module is able to be developed reduce number of modules increase power density in converter, which corresponds first contribution. As another contribution, a LVRT method based LC filter MVDC without additional circuit feedback capacitor current solve instability problem caused resonance spike filter. Five kV/50 kW SiC-based ±10 kV/200 PV converters were developed. Experiments system normal conditions are presented. experimental results verify effectiveness strategy.