Duty-ratio feedforward controller design for single-stage flyback CCM inverter
The transfer function of the flyback continuous conduction mode (CCM) inverter has a right-half-plane (RHP) zero that may severely degrade the control performance. If the conventional proportional–integral controller is applied, its control gain is limited by the existence of RHP zero and the inverter suffers from output current distortion. The value of the nominal duty has been used as a feedforward controller to eliminate the effect of disturbances and reduce the burden of the feedback controller. However, the conventional nominal duty performed poorly when it was utilised as a feedforward controller in flyback CCM inverter. A new nominal duty is proposed for single-stage flyback CCM inverter. Its output tracking performance is compared with that of the conventional nominal duty.
