公开(公告)号：US20190006974A1

公开(公告)日：2019-01-03

申请号：US16064502

申请日：2017-01-04

Applicant: DANFOSS POWER ELECTRONICS A/S

Inventor： Leandro DELLA FLORA ,  Anton SMITH

IPC: H02P21/18 ,  H02P21/22 ,  H02P27/12

CPC classification number: H02P21/18 ,  H02P6/20 ,  H02P21/22 ,  H02P27/12

Abstract: A method and apparatus for catching a rotating motor is described. Switches (typically the lower switches) of an inverter of a motor drive circuit are short-circuited for a brief period of time. The pulses generated by this process are analysed to determine the speed and direction of rotation of the motor. The pulses are checked to determine whether they are orthogonal. If they are, the motor velocity determination is deemed to be reliable and then motor is magnetised and normal motor control can be resumed. If not, the motor velocity determination is deemed to be unreliable and a magnetization pulse before the velocity determination step is repeated.