A Robust Voltage Sensor-Less Control for SiC Grid-Tied Inverter With Zero-Voltage Ride-Through

In this paper, a deadbeat control is proposed for a SiC grid-tied inverter to achieve voltage sensor-less, PLL-less and Zero-Voltage Ride-Through (ZVRT). In addition, an improved grid voltage prediction technology is introduced to enhance the robustness of the proposed deadbeat control which allows the voltage sensor-less PLL-less inverter to be operated under different grid impedance conditions. The operation principles of the proposed robust voltage sensor-less and PLL-less deadbeat control method are presented with the Lyapunov-based stability analysis. The proposed robust deadbeat control method has been implemented and verified on a 50kHz switching frequency SiC grid-tied inverter. The simulation and experimental results include low-voltage ride-through (LVRT) under large grid inductance are presented to verify its validity and advantages.