The unified power controller (UPFC) is, the most comprehensive device emanated so far from the FACTS (Flexible AC Transmission Systems) initiative. Installation of UPFC to control power flow has become an emerging topic in today¡¦s power industry, especially the deregulated market. By the use of UPFC, a high-speed and low-cost power electronic device, the line flows can be controlled in such a way that thermal limits are kept, losses minimized, stability increased, and contractual requirements fulfilled without violating the economic generation dispatch. To coupe with control signals to attain various control capabilities, it can be used to control both the active and reactive powers and voltage magnitudes altogether.
This thesis aims to study static UPFC models for power flow calculations. Basic operation of UPFC will be briefly reviewed. A new UPFC current-based model is proposed in this paper to improve existing power-based model by using the Norton Equivalent Theorem. The proposed model can be integrated with the ECI power flow model easily. The equivalent relationships between the new model and the traditional model will also be investigated. And the proposed current-based UPFC model will provide better convergent characteristics.
The Evolutionary Programming (EP) method was also proposed in this research to solve the UPFC control parameters to attain a global optimum. EP is an artificial intelligence process including reproduction, mutation, competition, and selection. Being a stochastic method, EP can avoid the local convergence problem and provide a better opportunity to reach the global or near global optimum. Using the test cases of 5-bus and Taipower systems, the test results proves that the new UPFC new model can successfully control active power and reactive power, and voltage magnitudes simultaneously with an effective process and a feasible solution.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0628102-112744 |
| Date | 28 June 2002 |
| Creators | Wang, Mu-Chi |
| Contributors | Shi-Jaw Chen, Whei-Min Lin, Ming-Tong Tsay, Ta-Peng Tsao |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0628102-112744 |
| Rights | withheld, Copyright information available at source archive |
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