MOTOR BEARING SYSTEM

[Problem] To precisely execute control related to a bearing so as to handle abnormality of a pump in a motor bearing system that has the bearing operable as a gas-lubricated bearing by the pump.[Solution] A motor bearing system 100 has: a slide bearing 3 operable as a gas-lubricated bearing by a pump 30; a rolling bearing 4; a switching mechanism 20 switching between the slide bearing and the rolling bearing; and a controller 50. The controller sets the switching mechanism to make the rolling bearing function when a motor rotation speed is lower than a first speed, and sets the switching mechanism to make the slide bearing function and controls the pump, so as to operate the slide bearing as a gas-lubricated bearing when the pump is normal and the motor rotation speed is equal to or higher than the first speed. In the case where the pump is abnormal, the controller sets the switching mechanism to make the rolling bearing function, and restricts the motor rotation speed to be lower than a predetermined speed even when the motor rotation speed is equal to or higher than the first speed.