Real time energy management and bus voltagedroop control in solar powered standalone DC microgrid

In this paper, different energy management techniques are investigated in solar powered standalone DC microgrid to 1) mitigate real time power mismatches and 2)improve DC bus voltage profile. If the battery state of charge (SOC) is between the maximum and minimum limits, the bidirectional DC-DC converter (BDC) connected to the battery is controlled to maintain DC bus voltage and power balance. Thus, the DC bus voltage is kept under stringent limits by adaptive droop control of BDC. The DC bus voltage set point is varied within the limits to account for SOC based battery management. If the battery SOC is unfit for charging/discharging, load management is deployed to serve the purpose. The boost converter connected to the solar panel (PV converter) is either used for optimal power point tracking (OPPT) or for voltage control in the absence of battery. The methods are investigated on the basis of bus voltage profile and utilization of solar PV source for different ranges of generation and loads using simulation and hardware.