Strategy Comparison of Power Ramp Rate Control for Photovoltaic Systems

Abstract

The high variability rate of solar irradiance can lead to fluctuations in the photovoltaic (PV) power generation. Consequently, it will bring severe challenges to the stable operation of the power grid. In order to mitigate those problems, the power ramp rate control (PRRC) is required by some utilities. Generally, the PRRC can be achieved by using two methods: energy storage systems (ESS) or active power curtailment. However, there is a lack of comparison of those methods on economic performance. Usually, the levelized cost of energy (LCOE) index is adopted to quantify and compare the cost for different methods. In previous work, an ideal value of ESS lifetime is mostly set to analyze the LCOE. However, the different ESS methods may require the battery to operate at different regimes (i.e., number of cycles and depth of discharger), which directly affects the lifetime. Thus, the battery aging is necessarily introduced to compare the LCOE. In order to fill this gap, this work demonstrates an evaluation of aging through the annual simulations using actual irradiance data. This is done for the LCOE of different PRRCs to determine which is the most cost-effective method. Index Terms-Active power curtailment, energy storage system, levelized cost of energy, photovoltaic (PV) energy, power ramp rate control.