Inductive current transformers (ITs) remain the most widely used voltage and current sensors in power systems. Among their many applications, one of the most crucial is certainly harmonic measurement. Recent literature indicates that due to their dynamic filtering behavior and nonlinear effects from their iron core, ITs can introduce errors of a certain percentage.

This article aims to delve deeper into the performance of two digital signal processing techniques, recently introduced to enhance harmonic measurements using ITs under identical experimental conditions: SINDICOMP and harmonic distortion compensation through polynomial modeling in the frequency domain (PHD). These methods were applied to two different voltage transformers with distinct specifications, using two measurement setups based on different architectures.

The impact of the voltage generator used during identification on the achieved accuracy is theoretically and experimentally evaluated. Modified versions of SINDICOMP and PHD compensation techniques are presented, which exhibit greater robustness against measurement setup non-idealities. The performance of these techniques is assessed using voltage waveforms resembling those encountered during normal operation in a real distribution network.