公开(公告)号：EP2901546A1

公开(公告)日：2015-08-05

申请号：EP13842927.9

申请日：2013-09-23

Applicant: BYD Company Limited

Inventor： LUO, Hui ,  DU, Zhiyong ,  ZHOU, Xuguang ,  ZHANG, Xinxin ,  CHEN, Xing ,  YANG, Taotao ,  CHENG, Lipin

IPC: H02P6/00

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：EP2831995A1

公开(公告)日：2015-02-04

申请号：EP13767963.5

申请日：2013-03-26

Applicant: BYD Company Limited

Inventor： DU, Zhiyong ,  CHEN, Xing ,  XIAO, Kai

IPC: H02P6/06 ,  H02P6/08 ,  H02P6/04 ,  H02P21/00

CPC classification number: H02P21/0035 ,  H02P21/0003 ,  H02P21/0021 ,  H02P21/22

Abstract: A method for controlling a rotation rate of an electric motor is provided. The method comprises following steps: judging whether an absolute value of a difference between an objective rotation rate of the electric motor and an actual rotation rate of the electric motor is greater than or equal to a predetermined value; and if yes, compensating a q axis current of the electric motor to adjust the rotation rate.