Suchergebnisse

This paper describes the setup and characterization of a set of wideband Current-to-Voltage (C-to-V) transformers equipped with symmetrical primary windings. The objective is to use the C-to-V transformer set to calibrate digital instrument transformer (IT) accurately at power frequency and within a wider frequency range to cover power quality aspects. The errors of the 50 A and the 200 A reference current transformer (CT) were within ±10 ppm and μrad at 50 Hz. The frequency responses of the two CTs up to 12 kHz were below 0.1 % and 0.2 crad. ; The project 17IND06 Future Grid II has received funding from EMPIR Programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme

All the measurement tasks, f.i. metering, protection and diagnostics, in electricity distribution and trasmission grids need instrument transformers (ITs) to scale voltage and current down to levels compatible with measuring instruments. Inductive voltage and current transformers (VTs and CTs) are still the most used ITs; however, their behaviour in presence of disturbances is not fully assessed. This paper analyses the behavior of CTs in presence of amplitude modulations, which is one of the disturbance under which the performance of Phasor Measurement Units (PMUs) has to be assessed. A measurement setup, able to test current transformers in accordance to the IEEE Std. C37.118.1 about the PMU performance testing, has been realized. Experimental tests on a commercial CT, changing the modulation frequency, are presented. ; The work reported here has received support from the EMPIR programme co-financed by the Participating States and from the European Union's

This report has been produced within the EMPIR project entitled Traceable Mechanical and Electrical Power Measurement for Efficiency Determination of Wind Turbines or 19ENG08 WindEFCY. More information about this collaborative research project can be found on the project's website https://www.ptb.de/empir2020/windefcy/home/. This report lists the technical requirements for the electrical power measurements and the definition of the measurands for nacelle test benches. ; The project 19ENG08 – WindEFCY has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme.