Cyber-Resilient Load Frequency Control in Modern Interconnected Power Systems: A Systematic Literature Review of Intelligent and Secure Control Strategies

Load Frequency Control (LFC) is very significant in the present
situation. With that, one can be certain to maintain and manage power
stability in relation to frequency changes while continuing reliable
power traded over different tie-lines, which are all actually occurring in
modern power systems. In addition, deregulated operation regimes are
also implicated, holding stability with LFC systems by email threats like
cyber security which occurred mostly during the process. This paper
provides an excellent review from the literature on LFC methodologies
not only of classical, robust, and optimization but intelligent and cyberresilient control strategies as well. Further development focused on
more modern approaches like model predictive control, sliding mode
control, fractional-order control, and the development of observerbased techniques for increased robustness and rejection of disturbances
in a complex multi-area system. Concomitantly, since then, conventional
metaheuristic algorithms become most popular and are amongst the
best for controllers optimized to be very transiently responsive and
stable in the steady state. Recent research trends are towards such
cyber-secure and resilient LFC designs which enable event-triggered or
self-triggered control, distributed/decentralized framework, resilient
observers, and new age methods like neural networks, fuzzy logic, or
reinforcement learning based real-time attack detection and defense.
This review provides a comprehensive analysis of 124 peer-reviewed
studies published between 2015 and 2026 on cyber-resilient LFC for
interconnected power systems. The analysis shows that around 38% of
the studies concentrate on resilient control strategies, while 29% focus
on cyber-attack detection and mitigation techniques. Approximately
18% investigate intelligent optimization and artificial intelligence (AI)-
based solutions, whereas the remaining 15% explore secure
communication frameworks, blockchain technologies, and distributed
control architectures. The review also highlights a clear shift in recent
research toward AI-enabled adaptive control, observer-based
estimation, event-triggered communication, distributed control
methods, and blockchain-supported secure LFC frameworks designed
for renewable-rich smart grids.