Preliminary Results from RR’C 2: Round Robin for Converter Losses, Phase 2

In the context of the revision of IEC 61800-9-2:2017 (IEC 61800-9-2, edition 1, Adjustable speed electrical power drive systems – Part 9–2: Ecodesign for power drive systems, motor starters, power electronics and their driven applications – Energy efficiency indicators for power drive systems and motor starters, Geneva, Switzerland, 2017) and the publication of an upcoming edition 2, several issues around converter losses need to be clarified. The testing method itself have been proven ambiguous as well as the reference losses which have been defined 5 years ago based on a simulation model that eventually appeared in a CENELEC standard EN 50598-2:2015 (CENELEC EN 50598-2, Ecodesign for power drive systems, motor starters, power electronics & their driven applications – Part 2: Energy efficiency indicators for power drive systems and motor starters, Brussels, Belgium, 2014). These values have never since been verified by actual tests of market products from different manufactures. The current test method has never been described in enough detail nor verified by independent test labs.

On its meeting on 6 September 2017 at EEMODS’17 in Rome, representatives from IEC WG18 (IEC, Subcommittee (SC) 22G for Adjustable speed electric drive systems incorporating semiconductor power converters, Working Group (WG) 18 for Energy efficiency of adjustable speed electric power drive systems), 4E EMSA (IEA Technology Collaboration Program on Energy Efficient End-Use Equipment (4E), Electric Motor Systems Annex (EMSA) (European Commission (EC), Commission Regulation No. 640/2009 of 22 July 2009 implementing Directive 2005/32/EC of the European Parliament and of the Council with regard to ecodesign requirements for electric motors, Brussels, Belgium, 2009)) and several independent testing labs (“project group”) decided to have 4E EMSA to undertake the project leadership and the organization of a round robin exercise for converters cooperation with IEC WG18.

Subsequently the round robin testing program for converter losses (RR’C) was established to serve as scientific base for establishing both a secured testing method and the necessary data base for converter losses through the entire range of 0.12 kW to 1000 kW that can be implemented in the coming revision of IEC 61800-9-2.

In Phase 1 (from November 2017 to February 2019) the main goal was to establish a testing method that would be both accurate and repeatable and that would be practical for industry and research testing labs. The “Uniform Testing Protocol” (UTP) has been made available as ed. 2 by November 2018. Phase 1 was completed, and the final report discussed during the IEC SC22G WG18 Meeting in Melbourne, Australia (19–21 February 2019). Phase 1 results will be published in a separate paper at EEMODS’19 (Agamloh E, Baghurst A, Brunner CU, Nielsen SB, Vezzini A: EMSA IEC WG 18, Round Robin of Converter Losses, Report of Results of Phase 1, Zurich, Switzerland, March 2019. Available at www.​motorsystems.​org).

In Phase 2 (from May 2019 to December 2020) the main goal is to validate the adapted testing method as well as establish a sufficiently wide data base of testing results over the entire range of converters between 0.12 kW to 1000 kW. In phase 2 the testing method shall also be verified in terms of “alternative” converter types such as active frontend converters.

This chapter shall report intermediate results of the current status of RR’C phase 2 – Converter losses.