Study of energy management for decreasing reverse power flow from photovoltaic power systems

When the volume of distributed generation (DG), including photovoltaic (PV) power systems, is increased, reverse power flow from DG may cause problems. To reduce the reverse power flow from PV power systems, energy management by use of storage batteries is expected to be a solution. In addition, the combination with load control is expected to reduce the storage capacity. In this study, energy management methods by use of the Supply and Demand Interface (SDI), which is a device to control DG, batteries and loads, are proposed and the effectiveness of the methods are evaluated by simulation analyses. The simulation results show that the amount of reverse power flow from PV power systems is reduced by the proposed energy management methods, and the load control is effective in reducing the reverse power flow. The required storage capacity to prevent the reverse power flow from the distribution line to the transmission line is also shown.