Standalone Photovoltaic Lithium-Ion Battery System with Sinusoidal-Ripple-Current Charging

The integration of solar photovoltaic (PV) into Electric Vehicle (EV) charging systems has witnessed a notable surge, driven by its clean, and low-pollution attributes. With EVs often parked idle during the daytime, the roofing of parking areas with PV panels offers an opportunity for ‘charging while parking’, presenting an economical solution for parking zones. Lithium-ion (Li-ion) batteries stand as the predominant choice for EVs. The Sinusoidal-ripple-current (SRC) method stands out as the primary charging approach when compared to conventional methods. Its zero-time feature enhances battery lifespan. However, in SRC charging, the PV system does not supply energy during the zero period, leading to unused energy in standalone PV battery systems. To maximize PV energy utilization and minimize battery charging time, efficient control strategies for standalone PV-Li-ion battery systems are proposed. Analysis indicates that out-of-phase converter operation with SRC charging is an effective strategy for faster charging and optimized PV utilization.