A technical solution on real-time monitoring of generator excitation system is introduced. In the solution， optical transducer measuring field current and voltage is used in complex electromagnetic environments in order to enhance the safety， accuracy and real-time of data collection. Through the simulation software for excitation system， recorded wave forms on unit excitation tests are analyzed and the excitation parameters of the static self-excitation unit are identified. The analysis of recorded wave data from the laboratory and field indicates the validity of the solution approach.