Hierarchical Power Flow Control of a Grid-tied Photovoltaic Plant Using a Battery-Supercapacitor Energy Storage System

Abstract A two-layer power flow control for a grid-tied photovoltaic plant equipped with battery-supercapacitor energy storage system is presented in this paper. The proposed strategy aims at simultaneously handling the intermittent nature of the solar radiation received by the photovoltaic collectors and the need to consistently supply the specified power taking advantage of the complementary characteristics of the energy storage technologies. It relieves the batteries from stress through the use of the photovoltaic and the supercapacitor to supply the high frequency power demands by means of hierarchical control. Extensive simulation results confirm the effectiveness of the proposed power flow control strategy.