This research work presents the improvement of the performance of synchronous generator in power system during line disturbances using an adaptive control scheme. This is necessary in order to ensure stability of power system during transient and other disturbances. The adaptive control scheme due to its robustness was incorporated into the excitation and steam valve controller to improve the stability of the system during fault or disturbances. This proposed scheme will also ensure proper frequency and voltage regulation during small perturbation to the mechanical power. The back stepping controller was first designed after which a sliding mode controller was introduced for evaluating the control variables (gains) of the back stepping controller. The performance of the developed scheme was compared with the results obtained when coordinated immersion and variance control method was used, using settling time of power angle, relative speed of recovery, transient potential and input mechanical power as performance metrics. The obtained results of the adaptive control scheme for the settling time of the power angle of the system is 0.25 seconds, while that of the relative speed of recovery, transient potential stability and input mechanical power are 0.2 seconds, 0.2 seconds and 0.21 seconds respectively. The immersion and variance control recorded a settling time of 0.26 seconds for the power angle of the system, 0.25 seconds for the relative speed of recovery, 0.95 seconds for the transient potential stability and 0.92 for the input mechanical power.