水电机组在线监测中同步整周期采样实现策略

水电机组在线监测系统中常用定时采样方法，采集数据量大，且频谱分析中由于采样频率和信号频率可能不一致，造成频率泄露和相位漂移，不能准确反映机组当前运行状态。文中构建了一种同步整周期采集策略：每次采集的起始点由键相信号来决定，使得每次采样数据具有相同的相位基准，转子每转1周，每个测点采集固定数量的数据，克服频谱分析的泄漏效应与栅栏效应，并且可准确提取信号中的相位，提高了数据采样和分析的精度。

Application of Synchronous Whole-periodic Sampling in the Hydropower On-line Monitoring System

Fixed time sampling is commonly used in the hydropower on-line monitoring system, which requires tremendous data collection. The inconsistent frequency of sampling and signal in frequency spectrum analysis may cause leakage of frequency and phase excursion, affecting the correct representation of the state of the system. By applying synchronous whole-periodic sampling, that is, each starting point of data collection is determined according to the key signal, which provides the same phase datum for every data collection. Every time the rotor makes a circle, a fixed amount of data is collected, so that both the leakage effect and picket fence effect in frequency spectrum analysis are prevented. And the phase in the signal can be exactly extracted, improving the accuracy of data collection and analysis.