A Stochastic Optimization Method for Energy Storage Sizing Based on an Expected Value Model

Abstract

Energy storage technologies have been rapidly evolving in recent years. Energy storage plays different roles in various scenarios. For electricity consumers, they are concerned with how to use the energy storage system (ESS) to reduce their costs of electricity or increase their profits. In this paper, a stochastic optimization method for energy storage sizing based on an expected value model for consumers with Photovoltaic Generation (PV) is proposed. Firstly, the Gaussian mixture model clustering method is used to cluster the historical load and PV data and calculate the probability of each cluster. Secondly, the optimal model of total system profit is established. Finally, according to the expected value model, the optimal ESS power and capacity are determined. Two case studies are used to demonstrate the calculation of optimal ESS capacity. The results obtained by the method proposed in this paper are compared with the results produced by the deterministic method. Through the analysis and comparison, the validity and superiority of the method proposed in this paper are verified. The profits obtained by the method proposed in this paper are 0.87% to 127.16% more than the deterministic method.

Frequency Regulation Adaptive Control Strategy of Wind Energy Storage System for Wind Speed Uncertainty

“…There are two operational requirements for energy storage-assisted wind farms to participate in frequency regulation: (1) maintain reasonable SOC and (2) improve the Energies 2024, 17, 2523 4 of 14 frequency modulation reliability of the air storage system. It is worth noting that, in most previous studies, SOC ref recovery base point (SOC ref ) was set as the fixed point 0.5 [16]. However, in wind power systems, due to the randomness of wind speed, SOC ref is set as the reference point, which may cause the energy storage to need frequent charging and discharging to recover its SOC, which will not only shorten the service time of the energy storage but also bring instability to the power grid.…”

“…Therefore, it is urgent for high-quality frequency modulation resources such as energy storage to provide auxiliary frequency modulation means to meet the frequency modulation requirements of the system [14]. However, state of charge (SOC), as one of the key factors for the efficient utilization of energy storage [15,16], must consider its management in the frequency modulation process. Authors of [17] propose that, in the isolated island state, the frequency modulation reliability of air storage and SOC recovery base point are optimized by taking the minimum deviation of the frequency modulation power of air storage as the goal.…”

Review of Voltage and Reactive Power Control Algorithms in Electrical Distribution Networks

“…Electricity users are interested in using the ESS to reduce electricity costs or increase profits. ESS can flexibly adapt at different time scales and may be considered as a variable energy source or variable load [54]. ESS may be operational at specific times or in critical situations [2,55].…”

Frequency regulation optimization for wind storage based on frequency regulation reliability and state of charge in isolated island off‐grid

“…To avoid the frequency regulation of high discharge depth, a charge‐state feedback control strategy for wind turbine battery hybrid power systems has been proposed 17 . The real‐time frequency offset of the power grid and the SOC signal of batteries have been used to divide the SOC, 18 and the states of the fan and battery states were considered. A control technique, where wind storage can jointly participate in frequency regulation to maintain the SOC near 50%, has been proposed.…”