No abstract

No abstract

No abstract

The N3 power plant of Taipower is located in the southern tip of Taiwan and connected to the power pool by four out-linking 345-kV overhead transmission circuits. There are two 951-MW generators. Each generator occupied 11% of the system peak load in 1985 when the generator was in commercial operation. Since Taipower is an isolated system, at the N-2 conditions, those generators were reduced to 75% loading to protect the power system. By the way, to avoid damage of negative sequence current (NSC), the limits of the N3 power plant are stricter than those in the IEEE Standard. However, in 2010, the capacity ratio of each generator in the plant to the system peak load has been reduced to 3% only. To increase the economic benefit of those generators, it is required to reassess the operation limits of NSC. EMTP was used to calculate the levels of NSC from the out-linking transmission circuits. From the results of this study, the effects of NSC could be ignored when the four out-linking circuits are in N-0, N-1, and N-2 conditions. The generators can be operated in full loading under these conditions. The modifications to the NSC limits of the N3 power plant are also suggested.

The purpose of this paper is to develop an advanced load flow program incorporating induction motor load model for power system voltage stability analysis. To meet this purpose, moditication of a conventional load flow program is introduce$ The developed program is applied to study the Taiwan power system where the maximum power transfer capability of transmission system is now greatly concerned The results of the study show that the maximum loading condition and voltage stability limit will be estimated more accurately when the induction motor load model is incorporated.