Ripple Reduction Without Current Sensing for AC‐DC Boost Converters

This paper proposes a current sensorless ripple reduction control method for AC‐DC boost PFC converters operating in discontinuous conduction mode (DCM), aimed at enhancing power quality for sensor‐integrated systems. Conventional AC‐DC converters often rely on bulky electrolytic capacitors to suppress low‐frequency voltage ripple, which poses challenges in terms of size, cost, lifespan, and reliability. Existing methods to reduce ripple, such as auxiliary circuits or harmonic current injection, require additional components and sensing circuits, complicating implementation and increasing noise susceptibility. The proposed approach eliminates the need for current sensors and harmonic injection circuitry by dynamically adjusting the duty cycle based on input voltage and voltage feedback, thereby simplifying the control architecture and reducing hardware complexity. A Type‐III compensator is incorporated to improve dynamic performance and ensure fast transient response, which is especially critical for precision analog front‐ends and ADC stability in sensor‐based applications. Both simulation and experimental results confirm the effectiveness of the proposed method in minimizing DC‐link voltage ripple and maintaining stable power delivery, while significantly reducing the required capacitance. The results demonstrate the suitability for compact, high‐reliability power systems in sensing applications.