Power control strategy and economic analysis using physics-based battery models in standalone wind–battery systems

Abstract

Lithium-ion battery storage is coupled with wind power systems to address the issue of power imbalance. Operating wind turbines continuously at a maximum power point (MPP) might dump excess power based on the load demand. Manufacturer provided battery life is for lab conditions and might not replicate under real-life conditions. To address these issues, we (a) propose a power management and control strategy to avoid dumping of excess power, (b) calculate yearly capacity-fade using a physics-based electrochemical–thermal battery model for real-world operating conditions, and (c) study the financial impact of storage on the cost of wind energy generation. The power management and control strategy is designed to maintain a power balance in the system irrespective of the variations in wind speed, load demand and battery state of charge and can track the MPP or deviate from it to guarantee 0% dumping power. The formation and growth of the solid-electrolyte interface layer are modelled to calculate the battery degradation rate. Finally, seven reliability indices, including loss of energy expectation, annualised life cycle cost, and battery sufficiency, are compared for three locations with varying wind potential. The techno-economic analysis reveals that battery life and wind potential significantly impact the energy generation cost.