Solar PV intermittencies due to passing clouds with high ramp rates occurring for a short time produce a significant challenge to grid voltage and frequency regulations of a PV-rich microgrid. To compensate for these high ramp rates, battery and/or supercapacitors (SCs) are commonly employed using the control strategy based on a moving average (MA) or low pass filter (LPF). However, the traditional MA and LPF schemes suffer from memory and time lag effects, resulting in the need for increased storage size. To address these issues, this paper describes the design and implementation of a generic ramp-rate-based compensation strategy for smoothing the solar power output and meeting rapid load demands in grid-interactive microgrids using a hybrid multilevel storage system, consisting of high-capacity buffer storage such as battery system and hydrogen storage comprising a proton exchange membrane electrolyzer and a fuel cell, and short-term cache storage such as supercapacitors, integrated
Preconditioning heats or cools the battery to the optimum temperature range for charging. Goal: shorter charging times, longer service life of the storage tank.
This paper proposes a method for battery storage and supercapacitor (SC) hybrid operation toward improving EVs' performance. The adopted concept is established to regulate the level of charge for the SC to suit the immediate storage needs of the EV in such a way as to couple both storage devices. The results demonstrate that the current drawn from the battery has significantly reduced the discharging rate of the battery smoothed out compared to the EV without the SC. Also, the electric vehicle (EV) battery capacity is improved and the implementation of an SC eliminates the abrupt discharge of state of charge (SoC). The SC supports the EV by providing the necessary power when required. The simulation results demonstrate the contribution of SC to improving the battery performance and the reduction in discharging rate. The battery cannot be disconnected, while the SC could be, and power can be exchanged via supercapacitor. The SC is faster than the battery to maintain the optimum SoC
The variations in solar irradiance due to the weather changes can cause fluctuations in the outputs of solar photovoltaic (PV) systems. Such variations can be classified as fast or slow (steady state) fluctuations. The fast fluctuations of the output of solar PV systems can cause voltage and frequency fluctuations in the PV-powered grid-interactive microgrid and can negatively impact the overall system stability. Therefore, many countries incorporated grid codes to limit the rate of fast fluctuations of the injected PV power. A battery storage system with a moving average scheme is usually used to compensate for the fast rate of fluctuations. However, the traditional moving average scheme suffers from a memory effect that depends on previous values of PV output, causing the need for increased storage size. This paper presents the development of a novel direct compensation strategy using energy storage to mitigate the fast rate of solar PV power fluctuations for applications in a PV-pow