Design and implementation of modified SEPIC high gain DC-DC converter for DC microgrid applications

In DC microgrids, power converters are essential for interconnecting and controlling power flow from the renewable sources such as solar PV, wind, fuel cell, and so on with the DC grid link. A lot of DC-DC power converters available in the literatures are used to boost the low voltage from the renewable sources to the high voltage and also to track the maximum power from these sources. To boost the output voltage, high gain converters are required. To increase the static gain of the converters, many techniques such as using voltage lift, switched capacitor, coupled inductor, and so on are used. This paper presents a novel high gain DC-DC converter that does not use the above techniques for voltage boosting. An inductive reactive element is added in series with a switch to boost the voltage gain. This inductor is connected in parallel with the source voltage when the switches are in ON position and in series with the source when the switches are in OFF position. The proposed converter is designed to produce the output voltage of 380 V for the input of 48 V. The converter is designed to handle the power of 1 kW. With the use of the voltage boosting element, a maximum voltage gain of 28 is achieved and the efficiency of converter is about 91.9%. The performance of the proposed converter is simulated and analyzed for various conditions such as variation in input voltage, reference voltage, and load power and also for motor loads. The experimental prototype model is also built and the hardware results are shown in this paper to validate the simulation results.

Automated summary

This paper presents a novel high gain DC-DC converter that boosts voltage without traditional techniques, aiming to increase the output from 48V to 380V and handle power up to 1kW. With a maximum voltage gain of 28 and an efficiency of approximately 91.9%, the converter's performance is simulated, analyzed, and validated with experimental data under various conditions.