This paper presents a novel fuzzy logic based Two Degree of Freedom Proportional, Integral and Derivative controller (F2DPID) for load frequency control (LFC) in an interconnected two area multi-source power system. Spider Monkey Optimization (SMO) algorithm is used to optimize the controller parameters. Superiority of the proposed controller in terms of dynamic performances is established by comparing the results with conventional PID, two degree of freedom PID and fuzzy logic based PID controller. Initially, the study is carried out by considering the power system without any nonlinearity and then the study is extended by including nonlinearities like Governor Dead Band (GDB) and Generation Rate Constraint (GRC) in the same power system. The result is analyzed in terms of various time domain specifications such as settling time, peak undershoot, and peak overshoot of frequency and tie-line power deviations for Step Load Perturbation (SLP) of 1% in area-1.