Derivation of a Time-Domain Dynamic Model for a Liquid Air Energy Storage System for Frequency Control Ancillary Services

Renewable energy generation is currently the most pursued approach to reduce greenhouse gas emissions due to electricity generation. Because of the intermittency of renewable energy availability, energy storage systems are playing a central role in modern power systems. With the increasing demand for high-capacity energy storage systems, attention has recently been shifting towards large-scale alternative energy storage devices instead of the batteries. Liquid air energy storage is one of the potential alternative storage technology, that has gained rapid attention recently. Understanding the dynamic characteristics of an energy storage system is vital when deploying them in grid supporting ancillary services. This paper explores a novel dynamic model that accurately predicts the transient operation of a liquid air energy storage system based on the basic principles of operation of the liquid air energy storage system. The theoretically derived dynamic model is tested by computer simulations in a modified IEEE 9 bus test system. System dynamic responses and the LAES dynamic behaviors are analyzed for different frequency contingency events. The paper demonstrates that the proposed model can be utilized to assess the effectiveness of deploying liquid air energy storage systems in grid ancillary services in future research studies.