A novel control scheme for enhancing low voltage ride through capability of solar generation

This paper proposes an advanced coordinated control scheme for low voltage ride through (LVRT) of the smart solar inverter. In MATLAB Simulink, a two-stage three-phase grid-connected converter with a practical PV model is developed in several scenarios, including the zero voltage ride through (ZVRT), which is regarded as the most extreme case. The simulation result indicates the faster transient response and the better power quality, compared with previous strategies. Active power fluctuation is reduced and reactive power is produced with a specific gradient based on the depth of voltage dip to satisfy the grid code. A more precise solar energy reference is realized by the proposed strategy with novel controlling loops. It is worthy to mention that more power is captured and stored without any additional devices, due to the adaptive DC-Link voltage and the change of operating restrictions.