Multicell multi‐output converter to counter unbalanced input sources in nanogrid applications

Summary Nanogrid is an apt solution to encourage renewable power generation and counter the problem of global warming. It comprises of mostly the PV sources feeding both AC and DC loads. To meet out this scenario, a converter that can convert DC to both DC and AC is required. This paper proposes a hybrid converter providing both AC and DC output for DC input. The proposed converter is a derived form of Split‐Pi converter, known as hybrid Split‐Pi. It works in both boost and buck mode. Inherent shoot through problem of bridge circuit present in a Split‐Pi converter is eliminated as the shoot‐through period is utilized to charge the boost inductor of the proposed converter. Hence, enhanced output is obtained because of the absence of dead time operation. A hardware prototype is developed to validate the proposed converter. Proposed converter is tested for both buck and boost mode. Variation of AC and DC gain with change in duty ratio is observed. The output AC RMS and its THD is studied for different modulation index. Peak of output AC voltage is limited by the input DC voltage. To overcome this issue, the single cell proposed converter is extended to a multicell arrangement. Multicell arrangement integrates multiple input DC voltage sources having different voltage levels. It is simulated for different cases and outputs are discussed.