{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T16:53:44Z","timestamp":1782406424013,"version":"3.54.5"},"reference-count":38,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,4]],"date-time":"2022-08-04T00:00:00Z","timestamp":1659571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"EMPIR programme","award":["19NRM05 IT4PQ"],"award-info":[{"award-number":["19NRM05 IT4PQ"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The integration of renewable energy sources on a large scale in the electrical energy distribution systems, as well as the widespread of non-linear loads, has led to a significant increase in power quality (PQ) disturbances. For this reason, PQ monitoring is also becoming a key task in medium voltage (MV) grids. The measurement of PQ at MV levels can only be performed using instrument transformers (ITs) to scale down the level of voltage and current to levels suitable for the input stage of PQ instruments. However, no international standards currently require the verification of the errors introduced by ITs in the measurement of PQ phenomena. Moreover, this issue is only partially addressed in the scientific literature, where papers dealing with specific and limited aspects of the problem can be found. For this reason, this paper aims to comprehensively assess the issue, proposing IT accuracy verification tests for different PQ parameters. First, a set of PQ phenomena relevant for IT testing is chosen, as well as the associated ranges of variation, based on a review of the enforced standards and the scientific literature. For each selected PQ phenomenon, possible performance indices and test waveforms are proposed. Finally, the proposed procedure is validated by applying it to the characterization of two different types of commercial voltage transformers.<\/jats:p>","DOI":"10.3390\/s22155847","type":"journal-article","created":{"date-parts":[[2022,8,5]],"date-time":"2022-08-05T02:12:39Z","timestamp":1659665559000},"page":"5847","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["How Instrument Transformers Influence Power Quality Measurements: A Proposal of Accuracy Verification Tests"],"prefix":"10.3390","volume":"22","author":[{"given":"Gabriella","family":"Crotti","sequence":"first","affiliation":[{"name":"Istituto Nazionale di Ricerca Metrologica (INRIM), Str. delle Cacce, 91, 10135 Torino, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5387-0371","authenticated-orcid":false,"given":"Yeying","family":"Chen","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt (PTB), Parkplatz, Bundesallee 100, 38116 Braunschweig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huseyin","family":"\u00c7ayci","sequence":"additional","affiliation":[{"name":"Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK), Tunus Caddesi No:80, Kavakl\u0131dere, Ankara 06680, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9361-8309","authenticated-orcid":false,"given":"Giovanni","family":"D\u2019Avanzo","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi della Campania \u201cLuigi Vanvitelli\u201d, Via Roma 29, 81031 Aversa, Italy"},{"name":"Ricerca sul Sistema Energetico-RSE S.p.A, Via Rubattino, 54, 20134 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0922-883X","authenticated-orcid":false,"given":"Carmine","family":"Landi","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi della Campania \u201cLuigi Vanvitelli\u201d, Via Roma 29, 81031 Aversa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Palma Sara","family":"Letizia","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Ricerca Metrologica (INRIM), Str. delle Cacce, 91, 10135 Torino, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Luiso","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi della Campania \u201cLuigi Vanvitelli\u201d, Via Roma 29, 81031 Aversa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5098-9396","authenticated-orcid":false,"given":"Enrico","family":"Mohns","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt (PTB), Parkplatz, Bundesallee 100, 38116 Braunschweig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabio","family":"Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"VSL B.V. (VSL), Thijsseweg 11, 2629 JA Delft, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renata","family":"Styblikova","sequence":"additional","affiliation":[{"name":"Cesky Metrologicky Institut (CMI), Okru\u017en\u00ed 31\/772, 638 00 Brno, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5796-3906","authenticated-orcid":false,"given":"Helko","family":"van den Brom","sequence":"additional","affiliation":[{"name":"VSL B.V. (VSL), Thijsseweg 11, 2629 JA Delft, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1152","DOI":"10.1016\/j.rser.2017.04.121","article-title":"Review of harmonic analysis, modeling and mitigation techniques","volume":"78","author":"Kalair","year":"2017","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_2","unstructured":"(2015). Electromagnetic Compatibility (EMC)\u2014Part 4\u201330: Testing and Measurement Techniques\u2014Power Quality Measurement Methods (Standard No. IEC 61000-4-30)."},{"key":"ref_3","unstructured":"(2017). Power Quality Measurement in Power Supply Systems\u2014Part 2: Functional Tests and Uncertainty Requirements (Standard No. IEC 62586-2)."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Crotti, G., Giordano, D., D\u2019Avanzo, G., Delle Femine, A., Gallo, D., Landi, C., Luiso, M., Letizia, P., Barbieri, L., and Mazza, P. (2020, January 25\u201328). Measurement of Dynamic Voltage Variation Effect on Instrument Transformers for Power Grid Applications. Proceedings of the 2020 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), Dubrovnik, Croatia.","DOI":"10.1109\/I2MTC43012.2020.9129354"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1322","DOI":"10.1109\/TIM.2018.2880060","article-title":"Compensation of Nonlinearity of Voltage and Current Instrument Transformers","volume":"68","author":"Cataliotti","year":"2019","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3841","DOI":"10.1109\/TIM.2019.2905908","article-title":"Compensation of Current Transformers\u2019 Nonlinearities by Tensor Linearization","volume":"68","author":"Collin","year":"2019","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Kaczmarek, M., and Brodecki, D. (2021). Transformation of Transient Overvoltages by Inductive Voltage Transformers. Sensors, 21.","DOI":"10.3390\/s21124167"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Crotti, G., Van den Brom, H.E., Mohns, E., Tinarelli, R., Luiso, M., Styblikova, R., Agazar, M., Cayci, H., Mazza, P., and Meyer, J. (2020, January 24\u201328). Measurement Methods and Procedures for Assessing Accuracy of Instrument Transformers for Power Quality Measurements. Proceedings of the 2020 Conference on Precision Electromagnetic Measurements (CPEM), Denver, CO, USA.","DOI":"10.1109\/CPEM49742.2020.9191698"},{"key":"ref_9","unstructured":"(1999). Instrument Transformers\u2014Part 7: Electronic Voltage Transformers (Standard No. IEC 60044-7)."},{"key":"ref_10","unstructured":"(2002). Instrument Transformers\u2014Part 8: Electronic Current Transformers (Standard No. IEC 60044-8)."},{"key":"ref_11","unstructured":"(2012). Instrument Transformers\u2014Part 2: Additional Requirements for Current Transformers (Standard No. IEC 61869-2)."},{"key":"ref_12","unstructured":"(2011). Instrument Transformers\u2014Part 3: Additional Requirements for Inductive Voltage Transformers (Standard No. IEC 61869-3)."},{"key":"ref_13","unstructured":"(2012). Instrument Transformers\u2013Part 103: The Use of Instrument Transformers for Power Quality Measurement (Standard No. IEC 61869-103)."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Crotti, G., D\u2019Avanzo, G., Landi, C., Letizia, P.S., Luiso, M., Munoz, F., and van den Brom, H. (October, January 29). Instrument Transformers for Power Quality Measurements: A Review of Literature and Standards. Proceedings of the 2021 IEEE 11th International Workshop on Applied Measurements for Power Systems (AMPS), Online.","DOI":"10.1109\/AMPS50177.2021.9586028"},{"key":"ref_15","unstructured":"(2019). IEEE Recommended Practice for Monitoring Electric Power Quality (Standard No. IEEE Std 1159)."},{"key":"ref_16","unstructured":"(2011). Voltage Characteristics of Electricity Supplied by Public Distribution Networks (Standard No. EN 50160)."},{"key":"ref_17","unstructured":"(2020). Assessment of Power Quality\u2014Characteristics of Electricity Supplied by Public Networks (Standard No. IEC 62749)."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Chen, Y., Dubowik, A., and Mohns, E. (June, January 29). Reference system for current sensor calibrations at power frequency and for wideband frequencies. Proceedings of the 2022 20th International Conference on Harmonics and Quality of Power (ICHQP), Naples, Italy.","DOI":"10.1109\/ICHQP53011.2022.9808745"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Chen, Y., Mohns, E., Seckelmann, M., and De Rose, S. (October, January 29). Traceable calibration system for non-conventional current sensors with analogue or digital output. Proceedings of the 2021 IEEE 11th International Workshop on Applied Measurements for Power Systems (AMPS), online.","DOI":"10.1109\/AMPS50177.2021.9586012"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1433","DOI":"10.1109\/TIM.2017.2648918","article-title":"An AC Current Transformer Standard Measuring System for Power Frequencies","volume":"66","author":"Mohns","year":"2017","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2322","DOI":"10.1109\/TIM.2014.2320835","article-title":"A Wideband Current Transformer Bridge","volume":"63","author":"Mohns","year":"2014","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Rusinaru, D., Manescu, L.G., Merfu, M., and Postolache, P. (2014, January 25\u201328). Power quality general levels in distribution networks. Proceedings of the 2014 16th International Conference on Harmonics and Quality of Power (ICHQP), Bucharest, Romania.","DOI":"10.1109\/ICHQP.2014.6842792"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Ka\u0161p\u00edrek, M. (2016, January 16\u201318). Voltage quality in the medium voltage distribution grid with connected wind power plants. Proceedings of the 2016 17th International Scientific Conference on Electric Power Engineering (EPE), Prague, Czech Republic.","DOI":"10.1109\/EPE.2016.7521814"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Mertens, E.A., Dias, L.F.S., Fernandes, F.A., Bonatto, B.D., Abreu, J.P., and Arango, H. (2007, January 9\u201311). Evaluation and trends of power quality indices in distribution system. Proceedings of the 2007 9th International Conference on Electrical Power Quality and Utilisation, Barcelona, Spain.","DOI":"10.1109\/EPQU.2007.4424212"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Meyer, J., and Kilter, J. (2014, January 11\u201313). Case studies for power quality monitoring in public distribution grids\u2014Some results of working group CIGRE\/CIRED C4.112. Proceedings of the 2014 Electric Power Quality and Supply Reliability Conference (PQ), Rakvere, Estonia.","DOI":"10.1109\/PQ.2014.6866790"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Gasch, E., Domagk, M., Meyer, J., Abdelrahman, S., Liao, H., and Milanovic, J.V. (2016, January 16\u201319). Assessment of Power quality performance in distribution networks part I\u2014Measurement campaign and initial analysis. Proceedings of the 2016 17th International Conference on Harmonics and Quality of Power (ICHQP), Belo Horizonte, Brazil.","DOI":"10.1109\/ICHQP.2016.7783325"},{"key":"ref_27","unstructured":"R\u00f6nnberg, S., Guti\u00e9rrez Ballesteros, E., Gil de Castro, A., Westman, M., and Brodin, M. (2019, January 3\u20136). Long-Term Power Quality Measurements in Medium Voltage Networks. Proceedings of the 25th International Conference and Exhibition on Electricity Distribution, Madrid, Spain."},{"key":"ref_28","unstructured":"(2016). Instrument Transformers\u2014Part 6: Additional General Requirements for Low-Power Instrument Transformers (Standard No. IEC 61869-6)."},{"key":"ref_29","unstructured":"(2018). Measuring Relays and Protection Equipment\u2014Part 118-1: Synchrophasor for Power Systems\u2014Measurements (Standard No. IEC\/IEEE 60255-118-1)."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"107535","DOI":"10.1016\/j.measurement.2020.107535","article-title":"Impact of inductive current transformers on synchrophasor measurement in presence of modulations","volume":"155","author":"Gallo","year":"2020","journal-title":"Measurement"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2298","DOI":"10.1109\/TPWRD.2004.843386","article-title":"Categorization and analysis of power system transients","volume":"20","author":"Bollen","year":"2005","journal-title":"IEEE Trans. Power Deliv."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"9005013","DOI":"10.1109\/TIM.2021.3111995","article-title":"Measuring Harmonics with Inductive Voltage Transformers in Presence of Subharmonics","volume":"70","author":"Crotti","year":"2021","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"109674","DOI":"10.1016\/j.measurement.2021.109674","article-title":"A new industry-oriented technique for the wideband characterization of voltage transformers","volume":"182","author":"Crotti","year":"2021","journal-title":"Measurement"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Crotti, G., D\u2019Avanzo, G., Giordano, D., Letizia, P.S., and Luiso, M. (2021). Extended SINDICOMP: Characterizing MV voltage transformers with sine waves. Energies, 14.","DOI":"10.3390\/en14061715"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1109\/TPWRD.2020.2978668","article-title":"Compensating nonlinearities in voltage transformers for enhanced harmonic measurements: The simplified volterra approach","volume":"36","author":"Toscani","year":"2021","journal-title":"IEEE Trans. Power Del."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Mingotti, A., Costa, F., Pasini, G., Peretto, L., and Tinarelli, R. (2021). Modeling Capacitive Low-Power Voltage Transformer Behavior over Temperature and Frequency. Sensors, 21.","DOI":"10.3390\/s21051719"},{"key":"ref_37","unstructured":"(2002). Electromagnetic Compatibility (EMC)\u2014Part 4\u20137: Testing and Measurement Techniques\u2014General Guide on Harmonics and Interharmonics Measurements and Instrumentation, for Power Supply Systems and Equipment Connected Thereto (Standard No. IEC 61000-4-7)."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Kasztenny, B., Fischer, N., Taylor, D., Prakash, T., and Jalli, J. (2016, January 4\u20137). Do CTs like DC? Performance of current transformers with geomagnetically induced currents. Proceedings of the 2016 69th Annual Conference for Protective Relay Engineers (CPRE), College Station, TA, USA.","DOI":"10.1109\/CPRE.2016.7914885"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/15\/5847\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:04:20Z","timestamp":1760141060000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/15\/5847"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8,4]]},"references-count":38,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["s22155847"],"URL":"https:\/\/doi.org\/10.3390\/s22155847","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,8,4]]}}}