一种新的自动准同期并列算法的研究

NOVEL ALGORITHM FOR AUTOMATIC SYNCHRONIZATION

自动准同期并列的关键是实现对并列双方电压参数的快速、准确测量。由于并列双方电压的频率不相等,难以同时对它们进行整周期采样,传统电压参数微机测量算法误差较大。该文提出一种基于加窗离散傅立叶变换(DFT)的利用相位进行频率校正的准同期并列新算法,该算法对电压信号的 2 个采样序列进行 DFT,并根据 2 次 DFT 结果及差值确定电压参数。它不需要对电压信号进行整周期采样,在采样频率固定不变的情况下,可以对频率在较大范围内变化的信号进行频率、幅值和相位的较精确测量。应用该算法同时测量并列双方电压参数,计算量较小,实现简单,仿真研究和科研实践证明了其可行性和有效性。

It is the core task for automatic synchronization device to estimate the parameters of both generator voltage and power system voltage rapidly and precisely. However, due to the difference between the two voltage frequencies, the synchronous sampling of the two voltage signals is difficult to perform simultaneously, and the error occurs when the traditional estimating algorithm is applied. Based on windowed DFT and spectrum correction technology, a novel algorithm, which needs no synchronous sampling, is present. It performs DFT on two sampling sequences of a voltage signal, and then makes use of the difference of two DFT analysis results to estimate signal frequency, amplitude and phase. Even if the sampling period is fixed, the algorithm can get high estimating precise when the signal frequency changes. The algorithm is easy to implement, and its feasibility and effectiveness is proved by simulations. The proposed algorithm has been applied in the automatic synchronization device, and expected performance is obtained.