Increasing flexibility in vulnerable power grids using electrochemical storage

Abstract

Developing a reliable power grid and investing in non-conventional renewable energy resources pose problems for low- and medium-income countries. Frequently, maintaining a robust power grid infrastructure can present challenges in terms of reliability, resilience, and flexibility. This article presents a methodology for improving power flexibility in susceptible power systems through the utilization of Battery Energy Storage Systems (BESS). The methodology entails the examination of power stability, operating conditions, and security criteria in order to identify suitable locations for storage allocation. A study was conducted utilizing the Electrical Transient and Analysis Program (ETAP®) software to simulate the Central American power transmission grid. The results of the study indicate that including storage systems to offer virtual inertia and backup during emergency situations is a recommended strategy for mitigating potential challenges. The study suggests that applying specific criteria for allocation and sizing at critical points in sensitive systems can enhance power transfer flexibility, eliminating potential constraints. The Central American electrical Power System, which faces power transfer limitations, is well-suited for BESS. In severe contingencies, such as when the system frequency drops to 58.75 Hz and power transfer between Mexico and Central America exceeds 300 MW with voltage levels below 0.97 pu, BESS can help mitigate these issues. The solution involves deploying BESS both centrally and distributively. Results show decreased instability, with power increases not exceeding 300 MW for more than 11 study cycles in all scenarios. The approach includes a BESS with an installed capacity of 1,060 MWh/160 MW and a virtual inertia of H=6s.

Keywords

• Energy storage systems
• Hosting capacity enhancement
• Load management
• Flexibility of power transfer
• Power system planning