A Simple Classification Method for Evaluating Influence Factors Affecting Instrument Transformer Accuracy

Recent developments in the power network have fundamentally altered its characteristics. It's evident that the introduction of renewable energy sources, electric vehicles, electronic converters, and similar technologies has brought about significant challenges for system operators and researchers. For instance, the actual currents and voltages in the grid deviate from the ideal 50 Hz sinusoidal signal due to power quality issues caused by various grid components and external factors. As a result, the equipment needs to be designed to withstand these conditions. This is particularly critical for instrument transformers (ITs), which are essential for tasks like protection, billing, and power management. To address this, this paper introduces a novel method to distinguish between influential and non-influential factors. The goal is to categorize these factors based on their impact on ITs. This classification will streamline testing procedures, saving time for manufacturers and end-users. The paper provides a detailed description of the method and applies it to a real-world case study using measurements from a commercial Rogowski coil. It's worth noting that this method can be applied to various types of ITs, making it a valuable tool for power system analysis and management beyond Rogowski coils.