This work demonstrates Automatic Generation Control (AGC) of two and three area reheat thermal system with nonlinearities. A Two Degree of Freedom Optimal Fuzzy Aided PID (2DOF OFAPID) controller is applied in all areas as secondary controller. The performance of proposed 2DOF OFAPID controller is validated through a comparative study with PID, 2DOF PID, fuzzy PID with filter-fractional order integral and OFAPID controllers. The pertinent parameters, Rules (Ri) and Membership Functions (MFs) are established by using Crow Search Algorithm (CSA) and an Optimized Adaptive CSA algorithm. The relevant flight length (fl) of each crow in CSA is optimized by Sine Cosine Algorithm (SCA) and is entitled as Sine Cosine Algorithm Optimized Adaptive Crow Search Algorithm (SCAOACSA). The primacy of suggested algorithm over CSA and SCA algorithms is demonstrated by solving 8 benchmark equations. From the comparative results, the SCAOACSA based 2DOF OFAPID controller is corroborated as admirable strategy to shorten the frequency and power deviations of interconnected power system.