Compensation Technique for Current Sensorless Digital Control of Bridgeless PFC Converter under Critical Conduction Mode

  • Kim, Tae-Hun ;
  • Lee, Woo-Cheol
  • Received : 2018.03.29
  • Accepted : 2018.06.26
  • Published : 2018.11.01


Critical conduction mode (CRM) operation is more efficient than continuous conduction mode (CCM) operation at low power levels because of the valley switching of switches and elimination of the reverse recovery losses of boost diodes. When using a sensorless digital control method, an error occurs between the actual and the estimated current. Because of the error, it operates as CCM or discontinuous conduction mode (DCM) during CRM operation and also has an adverse effect on THD of input current. In this paper, a current sensorless technique is presented in an inverter system using a bridgeless boosted power factor correction converter, and a compensation method is proposed to reduce CRM calculation error. The validity of the proposed method is verified by simulation and experiment.


Bridgeless boost converter;Current sensorless;Error compensation;Digital control


Supported by : National Research Foundation of Korea (NRF)