Improved reduce-order modeling of bidirectional interleaved boost with coupled inductors converter

In this paper, an improved reduced-order average modeling method for the bidirectional interleaved boost with coupled inductors (BIBCI) converter is proposed, based on the PWM and phase-shift dual-degree-of-freedom modulation and traditional reduced-order average model. Considering the power loss of the coupled inductor, the core loss, and the parasitic parameters of the inductors, capacitors, and switches in the circuit topology, the new model reflects the dynamic performance of the converter in a wide frequency domain more accurately than the traditional model. The small-signal model and transfer function are further deduced to provide a basis for the design of closed-loop controllers and have good engineering practicability. According to voltage source load or resistive load, the double-loop or triple-loop controller is designed correspondingly. The two models are theoretically analyzed and compared, and the proposed controller is verified by a 1.5 kW prototype.