Grid Active Power Control with Optimal Battery Usage and Demand Side Management

The active power control in photovoltaic (PV) systems is mainly based on the output power limitation. For residential applications, renewable energy sources (RES) can be supported by an energy storage system (ESS), together with manageable loads that increase the flexibility of the system, transforming the previous consumers into prosumers. Moreover, prosumers are expected to participate more actively in energy exchange operations, where the distribution system operator (DSO) or top layers from the hierarchical control structure provide the reference power that each participant must supply or demand. Therefore, in this work, a DSO supportive grid power controller (SGPC) for a PV and Battery-based residential system is proposed. The method ensures that the grid active power referenced from the DSO is followed for a predefined time. When possible, it maximizes the battery charging and the energy extraction from the PV. Furthermore, the proposed controller comprises a PI controller to track the power reference, an adaptive step flexible power point tracking (FPPT) algorithm, and demand side management is enabled by controlling low-priority local loads to further contribute to the grid power request. The simulation analysis verifies the effectiveness of the proposed method under different power requests.