Topology synthesis of coupled inductor based four port DC-DC converter for multi-input PV-battery application with autonomous mode selection

Multiport converters are the most reliable and integral component for latest renewable source integration with multiple inputs. This article is one among the kind, which proposes a novel Coupled Inductor based Four Port topology Multiport Converter (CI-FP-MPC) for integrating multiple PV sources with different voltages. The adoption of coupled inductor contributes an increased voltage gain with reduced stress on the switches and diodes. In addition, reduced number of switches and diodes for a four-port topology provides an increase in efficiency due to its reduced switching and conduction losses. Also, soft switching techniques for zero-voltage-switching in switches and zero-current-switching in diodes transfers a smooth commutation between the mode transients and operating intervals. The proposed converter operates with two PV sources with battery as a source and load as well, paving to two modes of operation viz., TISO and DIDO mode respectively. The proposed topology is derived from the conventional high gain boost converter with an add-on of autonomous sensing and control logic to swap and control between the modes. To evaluate and validate its performance, the converter is developed in experimental setup with a power capability of 750 Watts. The control logic and duty cycle adjustments are supervised in Hardware-In-Loop (HIL) arrangement using dSPACE MicroLabBox. The results show increased efficiency, improved voltage gain and robust mode transition during load perturbations.