Super Twisting Sliding Mode Observer Based AC Voltage Sensorless Deadbeat Control for Grid-Connected Inverter

To improve the operational reliability of grid-connected inverters and reduce the impact of AC voltage sensor failures, a grid voltage observation method based on a super twisting sliding mode observer (ST-SMO) is proposed, and a deadbeat control (DBC) strategy for grid-connected inverters based on grid voltage observation values is designed. Compared with conventional SMO, the designed ST-SMO can suppress sliding mode noise and improve the observation accuracy of grid voltage through equivalent feedback gain term. The effectiveness of the proposed method is verified through detailed comparative simulation results.