Sensorless current rebuilding strategy in a single phase bridgeless PFC

Bridgeless PFC is a one-stage AC/DC rectifier. Such a solution achieves higher efficiency compared to traditional PFC topologies (diode bridge + DC/DC converter). However, the input AC voltage must be measured before the input inductor. Line current sensing is expensive or produces load dependent loss. This paper presents a solution that avoids the use of an input current sensor. Instead, the current is rebuilt inside a digital device (FPGA) by indirectly measuring the voltage across the input inductor.