Patent ID: 9225283
Filing Date: 2015-12-29
Classification: H02P

Abstract:
1. A motor control device, comprising: an inverter configured to invert DC voltage into AC voltage at a specified PWM frequency by PWM control using a power device to apply the AC voltage to a motor; a power device temperature obtaining unit configured to obtain a temperature of the power device of the inverter; a motor temperature obtaining unit configured to obtain a temperature of the motor; a power device temperature determination level storage unit configured to store a power device temperature determination level; a motor temperature determination level storage unit configured to store a motor temperature determination level; a PWM frequency storage unit configured to store at least two PWM frequencies including a high PWM frequency higher than the specified PWM frequency, and a low PWM frequency lower than the specified PWM frequency; a power device temperature determining unit configured to determine whether or not the temperature of the power device is equal to or higher than the power device temperature determination level; a motor temperature determining unit configured to determine whether or not the temperature of the motor is equal to or higher than the motor temperature determination level; and a PWM frequency selecting unit configured to select a PWM frequency to be given as a command to the inverter, from the specified PWM frequency and the at least two PWM frequencies on the basis of determination results of the power device temperature determining unit and the motor temperature determining unit, wherein when the temperature of the power device is lower than the power device temperature determination level, and the temperature of the motor is lower than the motor temperature determination level, wherein when the temperature of the power device is lower than the power device temperature determination level, and the temperature of the motor is equal to or higher than the motor temperature determination level, wherein when the temperature of the power device is equal to or higher than the power device temperature determination level, and the temperature of the motor is lower than the motor temperature determination level, wherein when the temperature of the power device is equal to or higher than the power device temperature determination level, and the temperature of the motor is equal to or higher than the motor temperature determination level,