(19)

(11)

EP 2 992 536 A1

(12)

(43) Date of publication: 09.03.2016 Bulletin 2016/10 (21) Application number: 14719794.1 (22) Date of filing: 29.04.2014

(51) International Patent Classification (IPC):  H01F 5/02(2006.01) H01F 27/08(2006.01) H01F 27/32(2006.01) H01F 27/30(2006.01) (86) International application number: PCT/EP2014/058674 (87) International publication number: WO 2014/177534 (06.11.2014 Gazette 2014/45)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME (30) Priority: 29.04.2013 EP 13165777 (71) Applicant: ABB Technology AG 8050 Zürich (CH)	(72) Inventors: KEARNEY, Daniel CH-8004 Zürich (CH) DROFENIK, Uwe CH-5053 Zürich (CH) (74) Representative: ABB Patent Attorneys  C/o ABB Schweiz AG Intellectual Property (CH-LC/IP) Brown Boveri Strasse 6 5400 Baden 5400 Baden (CH)