Transportable Energy Storage System Planning for Mitigating Grid Vulnerability

Abstract

Recently, severe wildfires occurred in some countries like Australia and U.S., and wildfires usually threaten the security of the electricity grids. Therefore, it is crucial to identify the transmission interconnections that have insufficient power transfer capacity and take preventative actions to prevent the overload problem. In this paper, we have proposed a graph theoretic-based network expansion and transportable energy storage system (TESS) planning strategy. Through graph-theoretic analysis, the critical asset and limiting critical cut-set can be identified. Two novel criteria, namely transfer margin ratio (TMR) and adequacy ratio (AR), are proposed in this paper to assess the vulnerability and the reliability of the network based on graph theory. To reduce the vulnerability and to enhance the reliability of the grid, network expansion and TESS planning are proposed as two feasible methods. Therefore, this paper presents a risk-based network expansion and TESS planning strategy, and the investment plans are assessed by TMR and AR to make a final decision. The proposed method is verified in the IEEE 30-bus and IEEE 118-bus systems. The simulation results reveal that a graph theoretic-based planning strategy saves the total cost and reduces the shed loads in contingency.