Coordinated Control Framework for Frequency Transient Stability in Renewable Based Smart Grids

The deployment of renewable energy sources (RESs) changes fundamentally the dynamics of the grid, as the power electronics interface replaces the rotational inertia of the grid, thus decreasing the kinetic energy buffer capabilities of the system. This drop, along with the random and unpredictable characteristics of solar and wind energy, causes high-frequency power fluctuations, which are a serious challenge to multi-area frequency stability. In light of these highly volatile conditions, this research introduces a novel coordinated control framework design based on disturbance observer model predictive controller (DOMPC) with tilt fractional order proportional integral (TFOPI). DOMPC predicts disturbances and create optimal control actions using historical values and sends reference signals to the TFOPI controller. The TFOPI controller dynamically modifies these reference signals to ensure accurate control action. The starfish optimization algorithm (SFOA) fine-tunes the gains to improve the controller parameters, improving system performance under different operating conditions and disturbances. A multi-area interconnected power system is simulated extensively to test the suggested control method under different loads, RES intermittency, and grid emergencies. The proposed DOMPC-TFOPI system outperforms in terms of settling time, overshoot reduction, and uncertainty robustness. The results indicate that the proposed controller effectively reduces frequency variations in 2.13 seconds in area 1 and 2.20 seconds in area 2. This improvement helps maintain grid stability and enables a greater integration of RESs in smart grids.