This article presents an accurate and robust method to calculate the phase offset of a reference waveform, usually produced by a digital-to-analog converter (DAC) in IEC Std 61850-9-2 calibration systems. The phase offset is defined with respect to the rising edge of a reference clock signal, locked to the Global Positioning System (GPS). The proposed method relies on the synchronous acquisition of the DAC output and the clock signal. In the complex plane, where the discrete Fourier transform (DFT) is defined, the acquired signals are processed to compensate the nonideal sampling rate and windowing. The method performance and its dependence from noise and parameters are thoroughly characterized by means of extensive numerical simulations. Two validation approaches, experimental and software-based, confirm the proposed method as a valuable and robust solution for calibration purposes.

中文翻译：

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IEC 61850-9-2 校准系统中 DAC 相位偏移的表征

本文介绍了一种计算参考波形相位偏移的准确而稳健的方法，参考波形通常由 IEC Std 61850-9-2 校准系统中的数模转换器 (DAC) 产生。相位偏移是根据参考时钟信号的上升沿定义的，锁定到全球定位系统 (GPS)。所提出的方法依赖于 DAC 输出和时钟信号的同步采集。在定义了离散傅立叶变换 (DFT) 的复平面中，对采集的信号进行处理以补偿非理想的采样率和开窗。方法性能及其对噪声和参数的依赖性通过广泛的数值模拟得到了彻底的表征。两种验证方法，实验性的和基于软件的，