Field assessment of generators reactive capability

Utilizing generators' reactive capability to the full has become critically important over the last ten years. Voltage stability studies reflect actual power system conditions only as long as utilities assess their generators' actual reactive capability. Just as important, the system dispatchers and plant operators should be aware of the power system's actual reactive capability and have a good understanding of the impact that power plants' VAr production has on power system voltage. This paper describes the Public Service Company of Colorado's experience in maximizing its generating units' overexcited reactive capability. As a result of PSC's effort, an additional 500 MVAr of previously unused reactive power were "released" to the power system. Furthermore, this paper presents PSC's experience in educating power system dispatchers, power plant operators and engineering personnel on the subjects of voltage collapse phenomenon and VAr scheduling in a power system.<
>