Parameters setting and tuning for transition to a digital-based excitation system

There is a tendency for excitation control system to upgrade to the digital-based type, with the functions and benefits discussed in [1]. New computer models had been developed for representation of the renewal digital-based excitation system in transient stability studies after IEEE Std 421.5[2] adoption. This paper provides a guide line for replacement of the excitation control system from analog-based to digital-based. These techniques had been used on large steam generator excitation systems of a nuclear power plant in Taiwan. An optimal set of excitation system settings plays a very important role in power system stability. This paper will address the parameters setting and field tuning method for a self-excited exciter rewired to be separated-excited with station auxiliary power. The performance indices were also checked and compared with IEEE Std 421.2[3].