一种基于阶次分析的水电机组开机过程稳定性评价方法

开机过程中水电机组状态经历快速变化过程,因此分析机组开机这一典型过渡过程的稳定性具有重要意义。首先基于角度域平稳信号阶次分析方法,获取开机过程稳定性参数的三维阶次谱,然后从中选取起主导作用的转频分量的幅值变化趋势作为稳定性评价对象,再使用平均欧氏距离对历次开机过程转频分量幅值变化趋势差异性进行量化,由此实现对机组开机过程稳定性评价。选取某电站机组相近水头下多次开机过程实测数据的验证结果表明,该方法能较好地对机组开机过程稳定性异常状态进行识别,具有可行性。

A Method for Evaluating Stability of Hydroelectric Generating Set Starting Process Based on Order Analysis

The stability of the hydroelectric generating set during the start-up process directly affects the success of the unit. Therefore, it is of great significance to analyze the stability of the unit during the start-up process. Based on the order analysis method of stationary signals in the angle domain, the characteristic order related to the variation of rotating speed was extracted. The frequency component amplitude change trend was selected as stability evaluation object, which played a leading role. Then the average Euclidean distance was used to quantify the previous start-up process stability parameter trend difference. Thus, the stability evaluation of unit start-up process was realized. The measured data of the unit multiple start-up process under the similar water head of a certain power station were selected to verify the method. The results shows that the method can well identify the abnormal stability of the unit start-up process and verify the feasibility of the evaluation method.