The hierarchical energy management control for residential energy harvesting system

A hierarchical energy management system (EMS) for a residential power router is proposed to further reduce costs and stabilize the voltage of a load. There are ten modes of the EMS including three grid-connected modes and seven islanding modes. The state machine diagram shows the transition into and out of these modes. These transitions are based on switching criteria, over generation conditions, and under generation conditions. In comparison to previously published EMS, the proposed EMS could effectively minimize the expense on residential electrical utilities for daily cycling and stabilize the voltage of load when off-grid. The operations of the EMS are based on the local information such as current and voltage without needing the prediction of load and solar illumination. Simulation results reported in this paper verify the functionality of the proposed EMS for the system.