A simple technique of excitation voltage control with NNAVR (Neural Network Automatic Voltage Regulator) is proposed in this paper. Popular type of ANN (Artificial Neural Networks) known as RBF (Radial Basis Function) architectures with OLS (Orthogonal Least Square) algorithm is suggested to design AVR in order to prove its applicability and suitability. This proposed technique is implemented considering as SMIB (Single Machine Connected to Infinite Bus) system with linearized model of synchronous machine and its excitation system using Matlab/Simulink. The simulation results of RBF AVR, when compared with conventional AVR controllers show better performance, improve the transient and small signal stability of the system and above all its response is more suitable in case of load changing conditions.