an inductively coupled bidirectional dc-dc converter with a non-pulsating input current for renewable energy systems energy storage

The present study proposes a bidirectional dc-dc converter (bdc) that uses a non-isolated coupled-inductor (ni-ci). this converter can transfer power bidirectionally between the dc bus of a microgrid, supplied by pv or other renewable sources and energy storage system. the device exhibits a high voltage conversion ratio while using a few components. the converter applies the input inductance as a current ripple filter and uses a ci configuration to enhance the gain in boost mode. also, the turns ratio of a coupled inductor is implemented to enhance the voltage conversion ratio to lower voltage stress. in addition, the converter's operation is more efficient considering its soft-switching advantages. the duty cycle control is applied to generate the desired voltage on both sides of the converter by controlling the corresponding power switch. it is worth noting that the low-voltage side current ripple is not significant. besides, the results show an increase in voltage gain throughout boost mode and a decrease in voltage gain in the buck mode. furthermore, the converter is mathematically studied in the following, and a pid converter is designed to illustrate the converter's stability. finally, the practicality of the proposed ni-ci-bdc structure was validated by incorporating experimental results from a 200-watt prototype.