Since modeling and simulation are the two most effective tools that can be used in the design or analysis process, they play a vital role in developing such system. In many cases, they are the only possible means of making a safe engineering decision for a new concept of process for a large-scale system. Elsewhere, they are used as a critical element in the analysis of energy systems or to suggest a method of developing a novel and effective energy system model. Thus, in this study, simulations and test bed experiment were carried out to assess a low-power digital excitation system in order to validate its effectiveness. The excitation systems currently used by most of the power stations in the Republic of Korea were installed during the 1970s or 1980s. Unfortunately, it is difficult to seek technical assistance for them as they depend on foreign technologies, requiring a large sum to be paid when requesting one or more engineers to be dispatched. As such, technical updates have always been made by foreign companies, since it is not easy to make modifications to the system without the help of the original system developer. The technology developed in this study was designed to address such problem. The inability to conduct a test for an actual system can be solved by using a power system analysis program to analyze the characteristics of the controller. The study confirmed the system’s effectiveness, and the Test Bed was proven to be flexible and adequate for the experiment. The proposed excitation system is expected to increase the stability and economic effect of the system by optimizing existing systems. In the future, the authors plan to focus on student education by establishing an education system that allows students to learn about the digital excitation system and its simulation.