Dual-Mode interleaved flyback micro-inverter

With the increasing application of photovoltaic, the micro-inverter with interleaved flyback module operating in continuous conduction mode (DCM) and discontinuous conduction mode (DCM) is more popular. However, its difficult to control output current of interleaved flyback micro-inverter because the transfer function has right-half-plane (RHP) zero in CCM and low gain in DCM. To solve this problem, considering primary current and the output CL filter, a novel third-order model in DCM operation is proposed for theoretical analyzing. Then Quasi-Proportional-Resonant (Q-PR) controllers is adopted to apply the dual-mode control in flyback inverter, since the Q-PR controller can reduce the steady-state current tracking error, reject disturbance rejection capability, and improve transient performance. The effectiveness of the control method and the proposed model are validated by MATLAB/SIMULINK.