A PLL‐Less Grid Voltage Sensorless Improved Deadbeat Control for APF With LVRT Capability

ABSTRACT Traditional active power filter (APF) control suffers from limited dynamic performance due to PLL bandwidth and delays in grid voltage sensing. To address this, this paper proposes a novel sensorless and PLL‐less deadbeat control strategy. Grid voltage is predicted without physical sensors, and PLL is eliminated, thereby enhancing APF stability. Compared to conventional methods, the proposed strategy achieves faster dynamic response, zero steady‐state error, and improved harmonic suppression under low‐voltage ride‐through (LVRT) and load mutation scenarios. Real‐time identification of the equivalent inductance L ensures consistency between the control model and actual system dynamics. The deadbeat control is further enhanced to eliminate inherent control delays and achieve instantaneous current tracking with zero steady‐state error. Simulation and 1‐kVA experimental results demonstrate enhanced harmonic suppression, faster dynamic response, and better adaptability under complex grid conditions, confirming the method's practicality and cost‐effectiveness.