Stabilizing and Enhancing Frequency Control of Power System Using Decentralized Observer-Based Sliding Mode Control

This paper proposes a robust decentralized single-phase double integral sliding mode control (SMC) method combined with state observer for load frequency control of the multi-area power system integrated solar power sources. This study elaborates on how the proposed method secures the stability of the whole system as well as keeps frequency values within their safety ranges. Firstly, the designed observer ensures exact estimation of the actual states leading to convergence of estimated errors to zero. Secondly, a single-phase double integral sliding surface is designed completely based on estimated state variables achieved by the observer. A single-phase approach is employed to set up a sliding surface containing the initial point of the system trajectory and remove the reaching phase. Then, a new double integral SMC rule is developed to secure the finite time reachability as well as eliminate the oscillating and chattering issues. Finally, the effectiveness of the proposed method is validated thoroughly by simulation studies on LFC schemes in three-area power systems and the IEEE 39-Bus New England system to expose its advantages via various impact conditions.