TITLE:
Impact of Islanding on Governor Signal of Distributed Resources
AUTHORS:
Mahdi Ghadiri, Ali Moeini, Hossein Yassami
KEYWORDS:
Automatic Load Frequency Controller, Distributed Generation, Governor, Islanding Detection, Initial Value Crossing
JOURNAL NAME:
Journal of Electromagnetic Analysis and Applications,
Vol.3 No.2,
March
4,
2011
ABSTRACT: Technical and economical impacts of distributed resources have encouraged big industry managers and distribution systems’ owners to utilize small type of electric generations. One important preventive issue to develop these units is islanding situation. Expert diagnosis system is needed to distinguish network cut off from normal occurrences. It should detect islanding in time to disconnect the unit and prevent any additional failures in equipment. An important part of synchronous generator is automatic load-frequency controller (ALFC). This controller is designed properly to respond to load variations and to fix frequency at constant value when working alone as an islanding system and to control output power when operating in parallel with the main. In this paper, a new approach based on monitoring ALFC re-sponse with regard to input signal to governor is introduced. Numbers of initial crossing value are introduced as an index for islanding detection. Simulation results show that input signal to governor has different characteristics in common disturbances.