Digital metering, PMU applications and protocols with IEC communications

Sampled values (SV) from non-conventional instrument transformers – or Low Power Instrument Transformers (LPIT) – offer the potential for new industry applications which exploit digital real-time IEC 61850 communication on metering, grid control and the efficiency of the IEC 61850-SV protocol are investigated as follows:

Solar energy panels in the background high voltage power substation

Coordinator: Enrico Mohns

 

Metering. Non-conventional digital LPITs can be used for metering purposes. However, the effects of this digital approach on the metering chain needs to be understood, including the impact of the digital time-stamped representation of signals, the algorithms for power calculation, the different Analogue-to-Digital (A/D) converters (e.g. delta/sigma, SAR, etc.), and the different sampling clocks. Finally, metering products that use the SV protocol are already on the market, creating the need for the capability to independently evaluate their performance; supporting their successful market introduction. This research addresses these industry needs.

Grid control. Modern monitoring of the state and dynamics of transmission systems is presently realised through Phasor Measurement Units (PMUs). However, time and measurement integrity must be assured. These instruments typically use analogue inputs, but the availability of IEC 61850‑9-2 compatible digital inputs offers significant advantages, simplifying PMU design and sharing inputs with other applications. Nevertheless, this further complicates the measurement uncertainty and affects latency, both being critical barriers for many proposed real-time PMU applications to be adopted by industry. The suitability of the representation of voltages and currents provided by the present standards for the proper operation of an all-digital PMU is addressed, and the impact of this approach on PMU measurement uncertainty and latency is quantified. Guidance for future standards and validation methods is provided.

Efficient digital substation measurement data management. New data reduction methods with no impact on measurement uncertainty offer the potential for effective data reduction, significantly reducing digital substations communications bandwidth and system-wide latency, which in turn improves the overall efficiency and enables new real-time applications. Moreover, the use of these data reduction methods leads to additional functionality for measuring PQ parameters. As an example, if the voltage and current emissions in the frequency range of 2 kHz to 150 kHz are computed directly inside the standalone merging units (SAMU), the processed and compressed data can be transmitted via the same communication bus as for the SV data. This would ensure the same performance as conventional PQ measuring devices without needing very high sampling rates (300 kHz or higher) and data transmission rates.

For more information, see the project webpage >>

 

Parent project
Short Name:FutureGrid II,Project Number:17IND06

Participating Euramet NMIs and DIs

INRIM (Italy)

METAS (Switzerland)

MIKES (Finland)

PTB (Germany)

UME (Türkiye)

VSL (Netherlands)

Other participants

Alma mater studiorum Università di Bologna (Italy)
ComSensus, komunikacije in senzorika, d.o.o. (Slovenia)
Fundacion Circe Centro de investigacion de recursos y consumos energeticos (Spain)
Ricerca sul Sistema Energetico – RSE S.p.A. (Italy)
Synaptec Ltd (United Kingdom)
Università degli studi della Campania Luigi Vanvitelli (Italy)
University of Strathclyde (United Kingdom)

Information
Type
EMPIR
Field
Industry
Project type
Joint Research Project
Status
completed
Call
2017
Duration
2018-2021