5kW DC-coupling distribution power generation system based on photovoltaic and Aqueous Hybrid Ion battery

Abstract

Solar energy has the characteristics of intermittent and unstable, and it results in the negative impact on power quality of the utility grid while the penetration rate of the grid-connected photovoltaic generation system is increased. The energy storage system (ESS) can alleviate the negative impact on power quality of the utility grid so as to increase the penetration rate of the grid-connected photovoltaic generation system. Aqueous Hybrid Ion (AHI) battery contains no heavy metals or toxic chemicals, and it is non-flammable and non-explosive. Besides, AHI battery has the characteristics of high cycle life, safety and sustainability. A 5kW DC-coupling distribution power generation system (DPGS) based on photovoltaic and AHI battery set is presented in this paper. The operation modes of this DPGS are divided into self-consumption, charging/discharging schedule and stand-alone. The maximum power efficiency from the solar cell array to the grid is 97.1%. The maximum power efficiency of the bidirectional DC-DC converter is 97.3% and the maximum power efficiency from the AHI battery set to the grid is 94.5%. Therefore, the power efficiency of this DPGS is very high.