DocumentCode :
1616886
Title :
Simulation and optimization of load shedding scheme for islanded power system
Author :
Wu, Cuicui ; Gao, Lin ; Dai, Yiping
Author_Institution :
Inst. of Turbomachinery, Xi´´an Jiaotong Univ., Xi´´an, China
fYear :
2010
Firstpage :
1
Lastpage :
6
Abstract :
The effect on system stability of load shedding has been a popular research topic for many years, especially in an islanded power system. But seldom studies gave full considerations to the actions of Primary Frequency Regulations (PFRs) and Overspeed Protection Control (OPC) systems of the generation units, which may have great impacts on the system responses against disturbances or emergency situations. When accidents occurred in the islanded power system, the power between generator units and load will be unbalanced. The rotating speed of steam turbine will clearly drop (rise) to a lower (higher) level. That may cause the action of load shedding control system (OPC of the generation units) to ensure the stability of the whole system. In this paper, a frequency response model incorporating an under-frequency load-shedding scheme is presented for islanded power system simulations and it is applied for a practical power system with both hydro and fossil fired power generators. Load shedding controls and OPCs are involved in the mathematic model. Some useful conclusions are obtained from the simulation results, based on which the mathematic model of the power system has been optimized in latter sections. Reasonable agreements are observed between the simulation results and the accident records. The simulation results also show that an optimized load shedding scheme may lead to better system stability which means the frequency oscillation will be reduced. When the PFR of hydropower isn´t operated during the speed governing process, the frequency response of the whole system will be much better. It also suggests that if more electric power is generated by fossil fired turbine units, the system could get an advantageous frequency response.
Keywords :
hydroelectric generators; load shedding; power system stability; steam turbines; OPC; PFR; fossil fired power generators; hydro fired power generators; islanded power system; load shedding; overspeed protection control; primary frequency regulations; steam turbine; system stability; Lead; Load modeling; Time frequency analysis; Turbines; Frequency Response; Load Shedding Scheme; System Stability;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Power System Technology (POWERCON), 2010 International Conference on
Conference_Location :
Hangzhou
Print_ISBN :
978-1-4244-5938-4
Type :
conf
DOI :
10.1109/POWERCON.2010.5666690
Filename :
5666690
Link To Document :
بازگشت