A Generalized Control Strategy for DC-DC Converters used in DC Microgrid with SWT, PV and FC

A generalized control approach for DC-DC converter is proposed in this paper for optimal DC voltage tracking control. The developed controller is used for both DC input voltage control of a buck converter and for output voltage control of an interleaved boost converter (IBC). These converters are widely used in DC microgrid systems that consist of fuel cell and other renewable energy sources. The DC microgrid in this paper contains a Small-scale Wind Turbine (SWT), a photovoltaic (PV) source and a fuel cell (FC) source which is used to stabilize the DC bus that feeds a load. The parameters of the optimal controller are optimized using the particle swarm optimization (PSO) algorithm and the stability of the controller is demonstrated using Lyapunov analysis. In addition, the designed controller regulates the PV system and SWT input voltages ensuring the two systems operate at their maximum power point (MPP). Furthermore, the control maintains the DC output voltage of the FC source at a desired constant value despite the current fluctuations due to the other sources.