This paper addresses one of the new and most important issues arising when low-power voltage transformers (LPVTs) are used in power network substations for evaluating, among others, the residual voltage measurement. Conversely to open-triangle inductive instrument transformers, the use of phase voltage transformers for measuring the residual voltage gets challenging due to the very high accuracy required for the three LPVTs. In this paper, a general expression to estimate the residual voltage measurement uncertainty, starting from the LPVTs accuracy, is presented. The effectiveness of the proposed approach is then confirmed with both Monte Carlo simulations and actual measurements on a general three-phase system.

中文翻译：

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残余电压测量不确定度评估的通用易用表达式

本文解决了在电网变电站中使用低功率电压互感器 (LPVT) 评估剩余电压测量等时出现的新的和最重要的问题之一。与开式三角形感应互感器相反，由于三个 LPVT 需要非常高的精度，因此使用相电压互感器测量剩余电压变得具有挑战性。在本文中，提出了从 LPVT 精度开始估计剩余电压测量不确定度的一般表达式。然后通过蒙特卡罗模拟和一般三相系统的实际测量证实了所提出方法的有效性。