In order to solve the problems which are caused by wind power and solar power on-grid, such as power quality, stability, reliability and so on, this paper proposes wind and solar micro-grid including energy storage system(ESS). The micro-grid uses two buses: AC bus and DC bus. Micro-source current is connected to the grid with the same inverter, which can reduce the micro-grid control difficulties. The energy storage system connected to the grid through the inverter could directly absorb energy from the grid. The DC side of the energy storage system using bidirectional DC / DC converter, which can keep the DC side of the battery storage stable.
Enhancement of Island Microgrid Operation by Frequency-sensor-based Controller of Battery Storage System