ELECTRIC SUPERCHARGER

摘要

Providing an electric turbocharger whose rotation speed is appropriately controlled so that the actual temperature of the motor does not show an overshoot response beyond the allowable level during the temperature increase even in a case where the time constant regarding temperature measurement is of a long time span. A speed control device for an electric turbocharger, provided with: a temperature sensor 17; and a speed limitation device 21 which limits the speed of the motor when the temperature level detected by the temperature sensor exceeds a limit control start temperature Tm, wherein the speed limitation device 21 is provided with: a limit control start temperature correction device 23 which decreases the limit control start temperature Tm in a case that the increase rate of the detected temperature exceeds a threshold; and a speed limitation setting device 25 which sets a speed limit level based on the temperature difference between the limit control start temperature Tm and the detected temperature T as well as based on an increase rate regarding the detected temperature, after the detected temperature exceeds the limit control start temperature, wherein the speed is limited to the speed limit level set by the speed limitation setting device 25.