Metrological Characterization of a Signal Generator for the Testing of Medium-Voltage Measurement Transducers

Abstract

Nowadays, voltage transducers in medium-voltage (MV) distribution networks operate in nonsinusoidal conditions while their calibration is still based on simple sine-wave tests. A more significant characterization could be achieved using complex multitone signals. However, this requires an MV generator able to apply arbitrary voltage waveforms to the transducer under test. The authors have recently proposed a simple MV signal generator that can be effectively employed for this purpose. In this paper, the performance of this MV generator has been carefully analyzed. A characterization procedure based on multisine excitation has been proposed and tested. In particular, the main causes of uncertainty have been identified and their impact on the accuracy of the generated voltage evaluated. The analysis considers both linear and nonlinear effects, such as harmonic distortion and hysteresis

Overcoming Frequency Response Measurements of Voltage Transformers: An Approach Based on Quasi-Sinusoidal Volterra Models

“…A two second time window (hence 100 fundamental periods) and 100 kHz sampling rate have been employed. The estimated FRF can be used to pre-filter the spectrum of the desired excitation signal, thus obtaining the signal v g to be applied at the input of the power amplifier [21], [22].…”

Simple skin effect compensation in cylindrical shunts

“…Its architecture resembled that of a voltage generator [7], [8] previously developed by the authors for the testing of medium voltage transducers; the architecture is shown in Fig. 7, while its block diagram is reported in Fig.…”

On-line fault detection technique for voltage transformers

“…The fifth order simplified Volterra model recalled in the previous section has been used to represent the behavior of a CVT under test (TUT) having 0.5 accuracy class, 200V/100V voltage ratio and 20 VA rated burden. Its primary winding has been connected to an arbitrary voltage generator, similar to that described in [28], able to generate the proper voltage signals required by the tests. Primary and secondary winding voltages of the TUT has been collected by using two highaccuracy resistive dividers.…”