Flywheel Energy Storage Supported Adaptive Energy Management Strategy for Solar-powered Electric Vehicle Charging Station

The large-scale integration of solar photovoltaic systems and electric vehicles into power systems result in technical challenges due to the volatile nature of the generation and electric vehicle load. The paper presents an energy-storage supported adaptive DC-link voltage regulation based energy management strategy for improving hybrid AC/DC microgrid stability. The proposed volatility based control approach improves hybrid microgrid stability under volatile electric vehicle loading and renewable energy fluctuations. The adaptive energy management strategy limits the overstress on flywheel energy storage depending on the flywheel SoC profile. Different load profiles and source intermittency are considered to analyze the effectiveness of the proposed strategy. The combined control strategy of the interlinking converter and flywheel energy storage in power exchange mode operation and independent mode operation achieve energy balance with the change in solar irradiation and the addition/disconnection of electric vehicles. In addition, real-time experiments are performed to validate the proposed energy management strategy under various volatile conditions. The hybrid AC/DC microgrid with proposed energy management strategy provided a frequency improvement of 0.44% and voltage improvement of 7.5%.