Testbed for static electricity meters approval under real‑world interference

Testing the effect of interference on the accuracy of electricity meters requires a standard measurement testbed for testing static electricity meters with an uncertainty of better than 0.1 %.

Image showing a home energy smart meter

Coordinator: Paul Wright

Testing the effect of interference on the accuracy of electricity meters requires a standard measurement testbed for testing static electricity meters with an uncertainty of better than 0.1 %.

Testbeds are used to generate current and voltage AC waveforms with a synchronised phase relationship for the type‑approval testing of revenue meters. Existing approval testing in the EU consists of simple stationary waveforms mostly consisting of the fundamental components with limited low frequency harmonics as specified in IEC 62052‑11. This standard outlines all the requirements a meter has to fulfil as well as the test methods used to demonstrate they have been achieved. Immunity testing to interference up to 150 kHz is already specified in IEC61000‑4‑19 which specifies simple tests to inject swept and modulated tones and testing laboratories already have testbeds for this. The adequacy of these existing 4‑19 tests has been called in to question by recent publications on meter errors. However, it is highly desirable to redeploy as many aspects of the existing apparatus as possible in new testbeds to save money for testing laboratories.

In order to develop new testbeds, capable of testing using real‑world signals, two different approaches are pursued. The first uses a split signal generation method similar to that specified and implemented for existing IEC61000‑4‑19 testing. The second method uses an arbitrary waveform technique replaying complex waveforms using a digital‑to‑analogue convertor and a transconductance amplifier. The ‘split signal’ method has the advantage of using existing apparatus already used by testing laboratories, but the difficulty of synchronising the split signals makes this more difficult and less versatile at producing complex waveforms. The ‘arbitrary waveform’ method should produce better fidelity and accuracy but would require new investment by testing laboratories if it is adopted for normative testing.

Reference designs of both types of testbed for meter type approval testing are available to standards committees ready for inclusion in a normative standard.

For more information, see the project webpage >>

Parent project
Short Name:MeterEMI,Project Number:17NRM02

Participating Euramet NMIs and DIs

CMI (Czechia)

JV (Norway)

METAS (Switzerland)

NPL (United Kingdom)

VSL (Netherlands)

Other participants

Universitat Politècnica de Catalunya (Spain)
Universiteit Twente (Netherlands)

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