Motor state determination method and device, and power supply system

The present invention provides a motor state determination method and device and a power supply system. The system where a motor is located comprises at least two power supply devices capable of supplying power to the motor. The method comprises the steps of: monitoring state information of a motor; and determining whether the state of the motor is in an outage state but not be shut down or not according to the state information. The state information of the motor is monitored to determine whether the state of the motor is in outage state but not be shut down or not so as to avoid the misoperation of a protection mechanism and improve the motor protection reliability. 本申请提供电动机状态确定的方法、装置和供电系统。电动机所在的系统包括至少两个能够为所述电动机供电的供电设备。该方法包括：监控个电动机的状态信息；根据所述状态信息确定所述电动机的状态是否为断电但未停机。本申请通过监控电动机的状态信息，据此确定处于电动机的状态是否为断电但未停机的状态，从而避免保护机制的误操作，提高了电动机保护的可靠性。