公开(公告)号：US09887647B2

公开(公告)日：2018-02-06

申请号：US14039984

申请日：2013-09-27

Applicant: SHENZHEN BYD AUTO R&D COMPANY LIMITED ,  BYD COMPANY LIMITED

Inventor： Hui Luo ,  Zhiyong Du ,  Xuguang Zhou ,  Xinxin Zhang ,  Xing Chen ,  Taotao Yang ,  Lipin Cheng

IPC: H02H7/08 ,  H02P21/00 ,  H02P6/00 ,  H02P6/12 ,  H02P6/34 ,  H02P29/024

CPC classification number: H02P6/12 ,  H02P6/34 ,  H02P29/0241

Abstract: A method for checking an out-of-step of a synchronous motor includes detecting three-phase currents of the synchronous motor; determining whether a relationship between the three-phase currents satisfies a preset requirement; and if no, determining that the synchronous motor is out of step. It is determined that the synchronous motor is out of step when amplitudes of each current of the three-phase currents are not equal or when the phase difference between the three-phase currents is not 120°.

公开(公告)号：US09887646B2

公开(公告)日：2018-02-06

申请号：US14039852

申请日：2013-09-27

Applicant: SHENZHEN BYD AUTO R&D COMPANY LIMITED ,  BYD COMPANY LIMITED

Inventor： Hui Luo ,  Zhiyong Du ,  Xuguang Zhou ,  Xinxin Zhang ,  Xing Chen ,  Kai Xiao ,  Lipin Cheng

IPC: H02H7/08 ,  H02P21/00 ,  H02P6/00 ,  H02P6/12 ,  H02P6/182 ,  H02P6/34

CPC classification number: H02P6/12 ,  H02P6/182 ,  H02P6/34

Abstract: A method for checking an out-of-step of a synchronous motor includes detecting electric degrees of the synchronous motor, in which the electric degrees comprise at least a first electric degree and a second electric degree detected at a preset interval, and the second electric degree is detected after the first electric degree; comparing the first electric degree with the second electric degree to obtain a comparing result; and determining that the synchronous motor is out of step when the comparing result satisfies a preset requirement. It is determined that the synchronous motor is out of step when the electric degree keeps unchanged or decreases progressively, or an increment of the electric degree is very small.