(19)

(11)

EP 3 881 422 A1

(12)

(43) Date of publication: 22.09.2021 Bulletin 2021/38 (21) Application number: 19889530.2 (22) Date of filing: 26.11.2019

(51) International Patent Classification (IPC):  H02M 7/04(2006.01) (52) Cooperative Patent Classification (CPC): H02M 7/487; H02M 3/33569; H02M 3/158; H02M 3/33538; H02M 3/33561; H02M 3/337; H02M 1/008; H02M 1/0058; H02M 1/007; H02M 1/0077; Y02B 70/10 (86) International application number: PCT/CN2019/120772 (87) International publication number: WO 2020/108460 (04.06.2020 Gazette 2020/23)

(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 (30) Priority: 26.11.2018 US 201862771438 P (71) Applicant: Huawei Technologies Co., Ltd. Longgang District Shenzhen, Guangdong 518129 (CN)	(72) Inventors: ZHU, Huibin Plano, Texas 75024 (US) DAI, Heping Plano, Texas 75024 (US) (74) Representative: Gill Jennings & Every LLP  The Broadgate Tower 20 Primrose Street London EC2A 2ES London EC2A 2ES (GB)