Power Converters for Integration of Electrical Sources to DC Microgrid

This paper presents new topology for integration of electrical sources to dc microgrid. The new topology consists of three legs and each leg consist of two switches. First leg switches are acting as boost converter for photovoltaic system. Second leg switches are acting as bidirectional dc-dc converter for charging or discharging energy storage unit (battery). Third leg switches are acting as bidirectional ac-dc half bridge PWM rectifier for 1-O utility grid. The proposed topology with power electronic converters are control the dc microgrid operation in both islanding mode and grid connected mode. Photovoltaic system with boost converter is controlled by Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) algorithm. Battery with bidirectional dc-dc converter is controlled by constant current control mode with PI controller. 1-O utility grid with bidirectional ac-dc half bridge PWM rectifier is controlled by constant voltage control mode with PI controller. These power electronic converters with control strategies are maintaining power management among integrated electrical sources in both islanding mode and grid connected mode operations. In islanding mode, the energy storage unit is utilized to compensate the load power and intermittence of solar power. The suggested converter with integration of electrical sources are simulated in MATLAB environment.