Analysis of a Flyback Current Source inverter under hybrid DCM-BCM operation

The Current-Source Flyback micro-inverter is widely used in ac-PV module applications, operated either on Discontinuous Conduction Mode (DCM) or Boundary Conduction Mode (BCM). However, each mode has its performance disadvantages (either low power density for DCM or low efficiency due to increased switching losses for BCM). To overcome the above, a hybrid DBCM operation is proposed hereafter, taking into consideration that a smooth transition between the two operating modes needs to be achieved in order to have good output power quality. The mathematical analysis for the hybrid operating mode is presented and validated through simulation and experimental results.