Influence of control in cycling degradation when batteries perform PV ramp-rate control

This work studies the importance of the correct selection of control parameters in order to avoid unnecessary cycling in batteries when they perform PV smoothing. The classic ramp-rate control method (CRRC) is studied and the key role of the state of charge (SOC) control is analyzed for 2-year simulation data, particularly the proportional gain's (K) influence. Depending on K, battery cycling degradation (CyD), power requirements, SOC limits and throughout energy performance were discussed. According to the results, the correct tuning could prolong battery lifespan by reducing cycling degradation up to 80% (depending on the fluctuation restrictions and K) and avoiding unnecessary energy losses, power requirements and undesirable SOC operation levels. Finally, a simple general rule is proposed to set K value when CRRC is used.