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数学模型对控制系统设计、改善系统的控制品质具有重要意义，而获取模型的机理法相对较复杂。分数阶模型是传统整数阶模型的扩展，对于一些难以用整数模型阶准确描述的系统，分数阶模型具有不错的效果，因此分数阶模型的运用是建模的一种新的尝试。文章利用频域响应数据依据 Levy 方法辨识出分数阶模型，并用这种方法得到超临界火电机组燃料-中间点温度、燃料-主汽压的分数阶模型。辨识结果表明此方法具有较好的拟合效果，其可以作为求取分数阶模型的有效方法。“,”Mathematic model of the control system is essential for the study of the controller design as well as the improvement of the control quality, but the mechanism modelling method is often more complex than the identification method to obtain the mathematical model. The fractional-order model is the extension of the traditional integral-order model, and the former is more accurate in some situations, so it is a new try to use the fractional-order model in the thermal process. The present paper proposes a method to identify the fractional-order model which is derived from the frequency response data according to the Levy’s method, and the models of fuel-intermediate point temperature and fuel-main steam pressure are achieved using the method. From the identified results we can see that the model has good fitting effect, so it suggests that this method can be used to achieve the fractional-order model.