Repetitive learning control for the correction of wound-type potential transformer measurement errors: Sensitivity analysis

Successful implementation of a transmission level harmonic measurement syst em requires accurate and reliable measurement of harmonic voltages and curr ents. Existing substation instrument transformers are designed for harmonic -free 60 Hz measurements. Hence, their use to measure harmonics leads to th e introduction of resonance as well as saturation errors in the measurement s. An on-line error correction method to correct for wound-type potential t ransformer measurement errors has been proposed in previous publications. T he error correction was formulated as an output tracking problem where the distorted measurements were used along with the experimentally developed tr ansformer model to reconstruct the transformer input. The scope of this pap er is to develop a sensitivity analysis for the error correction method wit h respect to the transformer parameters. Results of this analysis indicate that the sensitivity of the method with respect to the transformer paramete rs is quite low.