Device protection apparatus and device protection method

A device protection apparatus comprising:

• a first sensor for detecting temperature of a refrigerant used for cooling a device including a heat-generation part;
• a second sensor for detecting temperature of the device;
• and
• a controller that applies drive limitation to the device based on a first detected temperature detected by the first sensor, and a second detected temperature detected by the second sensor,
• wherein the controller
• calculates a temperature difference between the first detected temperature and the second detected temperature,
• applies the drive limitation to the device when the temperature difference is higher than a predetermined temperature difference threshold value, and
• applies the drive limitation to the device when the temperature difference is lower than the predetermined temperature difference threshold value and the second detected temperature is higher than a predetermined first temperature threshold value.