Stability Delay Margins for Single-Area Load Frequency Control System with Inverter-Based Air Conditioners Using Rekasius Substitution with Resultant Theory

Power system frequency regulation can benefit from the use of inverter air conditioners (IACs), which serve effectively as a controllable load. However, communication time delays are introduced when multiple IACs are aggregated and controlled via an open communication network, which negatively impacts frequency stability. This article primarily investigates the stability delay margins (SDMs) of a single-area load frequency control system (LFC) incorporating IACs. SDMs are computed using a frequency-domain precise approach based on Resultant theory and Rekasius substitution. We look into how the number of IACs and the proportional integral controller (PI) gains affect the SDM. The quasi-polynomial mapping-based root finder (QPmR) technique and MATLAB Simulink are used to confirm the theoretical results' accuracy.