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EP 3 881 085 A1

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(43) Date of publication: 22.09.2021 Bulletin 2021/38 (21) Application number: 18939915.7 (22) Date of filing: 16.11.2018

(51) International Patent Classification (IPC):  G01R 15/18(2006.01) G01R 19/00(2006.01) G01R 15/16(2006.01) G01R 31/00(2006.01) (52) Cooperative Patent Classification (CPC): G01R 31/00; G01R 15/18; G01R 19/00; G01R 15/16 (86) International application number: PCT/CN2018/115999 (87) International publication number: WO 2020/097933 (22.05.2020 Gazette 2020/21)

(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 Designated Validation States: KH MA MD TN (71) Applicant: ABB Schweiz AG 5400 Baden (CH)	(72) Inventors: WU, Liang Zhaoqing, Guangdong 526238 (CN) DENG, Zhonghua Guangzhou, Guangdong 511495 (CN) (74) Representative: Zimmermann & Partner Patentanwälte mbB  Postfach 330 920 80069 München 80069 München (DE)