EMRP-ENG61: Non-conventional voltage and current sensors for future power grids (Future Grids)

• Forschungsstelle: METAS
• Projektnummer: F-5212.30038
• Projekttitel Englisch: EMRP-ENG61: Non-conventional voltage and current sensors for future power grids (Future Grids)

Schlüsselwörter (Englisch)

Non-conventional instrument transformers, high voltage transmission, medium voltage distribution, power quality, harmonics, energy metering, electricity transport, smart grid.

Kurzbeschreibung (Englisch)

This joint reserach project focuses on the possibilities of novel non-conventional sensors for voltage and current measurement in power grids. Many of these technologies are already applied and promise wider bandwidth, and lighter weight, but they are not yet of the required metrological accuracy. The first generation of measurement systems installed in the European power network is getting old, and the systems are being replaced. There is therefore a need to ensure that appropriate technology is available that enables reliable and robust control and billing in future
power networks.

This project is part of the European Metrology Research Programme (EMRP, http://www.euramet.org/index.php?id=emrp); it is partly funded by the European Union on the basis of Decision No 912/2009/EC.

A more detailed description of the project may be found in the encloed publishable summary.

Zugehörige Dokumente

• ENG61_Publishable_JRP_Summary.pdf [PDF] 187 kB

Projektziele (Englisch)

The aim of the JRP is to support wider application of novel sensor technologies in future power networks. To complement the emergence of the new technologies, the most promising of them have been selected.
The specific objectives are to:?

• Design, manufacture and characterise a wideband sensor based on the optical Faraday effect for traceable calibration of non-conventional and conventional current sensors on medium and high voltage networks. The target uncertainty for current measurement is below 100 μA/A. (WP1)
• Apply a magnetic shielding technique to a Rogowski coil to improve its applicability for onsite measurement and calibration. The target is to reduce the proximity related influence to below 10 μA/A. (WP2)
• Develop a precision voltage sensor for the calibration of non-conventional and conventional sensors in medium voltage networks. The target uncertainty for voltage measurement is below 100 μV/V and the target bandwidth is 5 kHz. (WP2)
• Develop traceability for new non-conventional techniques not yet commercially available, such as using a fibre Bragg grating for interrogation of sensor networks, or measurement of capacitive current flow through a high voltage capacitor for PQ measurements. The target uncertainties are below 0.2 % and 0.3 crad. (WP2)
• Test the applicability of the sensors developed in the JRP on existing medium voltage (c. 20 kV) and/or high voltage (c. 100 kV) substations. (WP1 and WP2)
• Develop services for the calibration of non-conventional sensors with analogue output. The target uncertainties are 0.003 % and 0.003 crad. (WP3)
• Develop services for the calibration of transformers and non-conventional sensors with digital output in line with IEC 61850-9-2. The target uncertainties are 0.003 % and 0.003 crad. (WP3).

METAS is involved in WP3.

Abstract (Englisch)

METAS was mainly engaged in achieving 2 goals.

The first goal was to set up an infrastructure, mainly a software platform, for measurement data available through the IEC 61850-9-2 protocol, also called "sampled values" or SV. This protocol is becoming an established standard in the measurement equipment (instrument transformers) in electrical substations. It is also expected to play an enhanced role in other fields such as metering and smart grid control.

The second goal was to achieve a metrological evaluation of certain devices working with this protocol. METAS focused on two kinds of devices:

1. Commercial test sets suitable for nonconventional voltage and current sensor calibration in the field. The functionalities of the test set evaluated during the project are the analog signal generation (voltage and current) and their synchronous IEC 61850-9-2 representation.
2. Stand-alone merging units (SAMUs) used to retrofit conventional transformers in power network substations. A SAMU is essentially an analog-to-digital converter delivering its results in the IEC 61850-9-2 format.

Umsetzung und Anwendungen (Englisch)

The METAS results, especially the software platform, have been reused by other project partners, especially PTB and TU-Dresden for related research work.

We have also prepared new Calibration and Measurement Capybilities on the calibration of test sets and SAMUs and are ready to offer services in these new domains.

Publikationen / Ergebnisse (Englisch)

E. Mohns, A. Mortara, H. Cayci, E. Houtzager, S. Fricke, M. Agustoni, B. Ayhan: “Calibration of Commercial Test Sets for Non- Conventional Instrument Transformers”, Presented to AMPS 2017
M. Agustoni and A. Mortara: “A calibration setup for IEC 61850-9-2 devices”, IEEE Trans. Instrum. Meas. 66-6, pp. 1124-1130, 2017. 
M. Agustoni and A. Mortara: “A calibration setup for IEC 61850-9-2 test sets”, Digest CPEM 2016, Ottawa, July 1-6, p. 670-671, 2016.