A fuzzy tuning PID automatic voltage regulator for small salient pole alternators

Until recently diesel generating sets were mainly used for emergency/standby purposes. However, deregulation of the electricity utilities has created new applications for these units with a corresponding opportunity for market growth. These conditions necessitate an improvement in the overall control provided for such generating sets. This paper is primarily concerned with the economic and effective control of generated voltage. In a conventional automatic voltage regulator (AVR) this is achieved using analogue technology, but there are many advantages in employing digital technology. The increased functionality and improved cost effectiveness of microcontrollers, ensure that digital AVRs are becoming a viable option on small alternators. The implementation of such a digital AVR is described. Test results showing the voltage response to step changes in demand and application and rejection of load are provided to compare the performance of the new digital and conventional analogue devices.