Sensorless Control of a Bridgeless PFC Using a Low Pass Filter Model and a Linear PR Controller

Inhalt:
Compared with traditional power factor correction, PFC, converters, Bridgeless PFC reduces the conduction losses since the power conversion is carried out by only one stage. However, the measurement of the grid voltage and current become differential, increasing the cost and the circuit complexity. This paper proposes a solution that avoids the use of the sensor of the input current. Instead, the current is rebuilt inside a digital device (FPGA) by low-pass filtering the estimated voltage across the input inductor over time.