The constant increase of switching power converters in distribution and transmission grids pushes the need for harmonic measurements. Recent literature has shown that inductive Voltage and Current Instrument Transformers (VTs and CTs) can be used for harmonic measurements, but their accurate frequency characterization involves the use of quite costly instrumentation. In this context, this paper proposes an industry oriented technique for frequency characterization of medium voltage inductive VTs, involving instrumentation that, typically, is present in accredited laboratories or at VT manufacturers premises. In fact, it requires the generation of only sine waves and the measurement of: i) ratio and phase errors in sinusoidal rated conditions, the same prescribed by the international standards, and ii) ratio and phase errors with sine waves at 7 V from power frequency up to the first resonance frequency. The proposed technique, named SINDICOMP-LV, has been applied to medium voltage VTs and validated by the INRIM reference system for frequency characterization of VTs. Accuracy improvement with respect to the use of a conventional low voltage frequency sweep is up to one order of magnitude for the ratio error and up to 5 mrad for the phase over the considered frequency ranges, depending on the frequency value

配电和输电网中开关电源转换器的不断增加推动了对谐波测量的需求。最近的文献表明，电感式电压和电流互感器（VT 和 CT）可用于谐波测量，但其准确的频率表征涉及使用非常昂贵的仪器。在此背景下，本文提出了一种面向行业的技术，用于中压感应式 VT 的频率表征，涉及的仪器通常存在于经认可的实验室或 VT 制造商场所。事实上，它只需要生成正弦波并测量： i) 正弦额定条件下的比率和相位误差，与国际标准相同，ii) 7 V 正弦波从电源频率到第一谐振频率的比率和相位误差。所提出的名为 SINDICOMP-LV 的技术已应用于中压 VT，并通过 INRIM 参考系统对 VT 的频率表征进行了验证。与使用传统低压频率扫描相比，在所考虑的频率范围内，比率误差的精度提高了一个数量级，相位的精度提高了 5 mrad，具体取决于频率值