Voltage Transducers Testing Procedure Based on the Best Linear Approximation

Attention towards power quality issues in distribution grids has increased noticeably in the last decade. Power quality assessment and monitoring require voltage transducers capable of measuring both fundamental and harmonics with adequate accuracy. Beside this, a systematic but simple procedure for evaluating the measurement performance of voltage transducers, able to quantify the impact of linear and nonlinear effects separately has not been proposed yet. In this paper, a testing method based on the concept of Best Linear Approximation (BLA) is introduced. The excitation signals resemble the voltage waveforms typically found in distribution networks, while the impact of noise and nonlinearity is evaluated in terms of sample variances. The approach is applied to the model of a typical voltage transformer by means of numerical simulations.