الفهرس | Only 14 pages are availabe for public view |
Abstract Abstract Frequency control at emergency conditions is a prevailing field for discussion as the traditional solution for solving frequency disturbances becomes impractical solution with the new smartening process. The power system frequency may be subjected to a severe DROP during a massive loss of generation without a balanced compensation power for connected load demands. The emergency frequency control system traditionally depends on under-voltage and under-frequency load shedding techniques of power system feeders in cascading steps. As a result, the power system will suffer from series of internal and external disturbances leading to various degrees of blackouts due to cascading failures effect. The traditional electric power grids are developed to be smarter especially with control and protection issues underpinned by advanced measurement and communication technologies. This research presents a novel controlling actions to limit the probabilities of disconnecting loaded feeders from the power grid due to mal-operation of Under Frequency Load Shedding (UFLS) relays. The suggested controlling methods depend mainly on controlling Thermal Conditioning Loads (TCL) located at High Voltage (RV) level power network instead of disconnecting live loads. The first method is based on centralized controlling scheme with a hierarchical decision making between multi-controlling agents. While the second method depends on a decentralized controllers distributed among HV , network zones. The distributed controllers are used to classify the frequency condition to be either normal or emergency based on Decision Tree (DT) concept to minimize the false operation. The simulation of different faults during many operating scenarios by using Matlab software reveals that using the suggested methods yields proficient, proactive, and secured frequency control actions than traditional UFLS. |