Standalone Solar PV System Using DCMLI-DAB Converter with Battery Storage

Renewable energy resources are playing vital role in meeting the increasing demand of electrical power. The modern power electronics converters play a crucial role in converting extracted power to various forms. In order to balance the generation and utilization of power, electrical energy storage (EES) system is interfaced using bidirectional DC-DC converter (BDC). In this paper, a neutral point clamped multilevel inverter (NPCMLI) based dual active bridge (DAB) bidirectional DC-DC converter suitable for medium and high power applications is proposed. The DCMLI enables low voltage stress across the switches and reduction of total harmonics distortion (THD). The converter consists of NPCMLI on HV side and combination of H-bridges on LV side. It has attractive features like compact size and reliability. An islanded solar PV fed system uses proposed multilevel bidirectional converter with multiple batteries support. The system is designed and simulated for various load and source conditions.