Regulation of terminal voltage and output frequency of a variable-speed dual-excited synchronous generator by using a computer-based two-phase excitation system

A computer-based two-phase excitation system for a variable-speed dual-excited synchronous generator (DESG) has been implemented. The excitation system has an automatic frequency regulation (AFR) scheme and an automatic voltage regulation (AVR) scheme. The two regulation schemes control the excitation currents simultaneously, but set independently, to enable the DESG to supply power at constant frequency and constant terminal voltage while its rotor is driven at a variable speed as it is in the case of wind power generation systems. This paper describes the implemented prototype of the computer-based excitation system and its performance in real time. The experimental results show that the excitation system is flexible, portable, fast acting, and accurate