The Sensitivity Analysis Of The Influence Of Variation Of Unit's Inlet Parameters On Thermal Economy

Parameter variation of steam admission has an important effect on the economy of thermal power generating units, so the research and analysis for sensitivity of parameter variation on the economy has theoretical and realistic significance. Parameter variation of steam admission includes three parts: main steam pressure, main steam temperature and reheated steam temperature. It is well known that those changes usually be defined to be"systematic large perturbation". Even though the strength of this kind of perturbation is faint, it can spread to the whole system. So it causes the redistribution of flow of vapour-water and in turn it brings to the parameter variation of all different levels of extraction opening and exhauststeamend. So the analysis for parameter variation of steam admission is rather complicated, there is only four common methods: characteristic test, characteristic curve, partial derivative and project simplified back heating and so on.Basing on a unified physical model and a mathematical model about thermo-economics analysis for coal-fired power unit, this paper draws into a gradient operator matrix, and respectively sets up three intensity matrix computation models: the model about the influence of main steam pressure's changes on thermo-economics of power units, the model of main steam temperature's changes on it and the model of the reheated steam temperature changes on it. Then it puts forward a concept of"Intensity Matrix". By the computation of this paper, for a special unit, a certain parametric sensitivity factor has a particular relation with the load of this unit, and it reflects that sensitivity factor is an inherent nature of unit. By using fitted relation to calculate sensitivity factor value, it will be much conveniently to get the influence of the variation of parameter on coal consumption rate. Consequently, sensitivity factor could be directly used to qualitatively analyze and quantitatively analyze the influence of the variation of parameter on coal consumption rate. It provides a new tool for thermo-economics analysis,energy saving and energy efficiency of power unit.