Title |
Limit Resolution in the Decoupled UPFC Model for Power Flow |
Authors |
김태현(Kim, Tae-Hyeon) ; 서장철(Seo, Jang-Cheol) ; 임정욱(Im, Jeong-Uk) ; 문승일(Mun, Seung-Il) ; 박종근(Park, Jong-Geun) ; 한변문(Han, Byeon-Mun) |
Keywords |
Flexible AC Transmission Systems (FACTS) ; Unified Power Flow Controller (UPFC) ; Decoupled UPFC model for Power flow ; Limit Resolution ; Newton Raphson |
Abstract |
This paper presents new methods to resolve the important limits in the decoupled UPFC model for power flow, by which conventional power flow program can be performed with addition of two buses per one UPFC. In order to operate UPFC to the desired value, the series voltage and shunt current of UPFC should be computed. So a method of calculating these by simple equations after power flow is derived. However, the calculated magnitude of series voltage and/or shunt current of UPFC may not be allowed because of the UPFC limit ' to the ratings of inverters. In this case, the active power and the reactive power (or the voltage magnitude) of UPFC buses should be revised to resolve the limit. This paper proposes the Newton Raphson method to resolve these limits. Particularly, when resolving the series voltage magnitude, three strategies are proposed according to the priority of the active power and the reactive power (or the voltage magnitude). |