Carrier frequency setting method, motor drive system and carrier frequency setting device

摘要

Allow the motor to be driven so that the total loss of the motor loss and the inverter loss is small. In the relationship between the optimum carrier frequency that minimizes the total loss and the torque of the motor M, the lowest value of the optimum carrier frequency is derived, and the motor is within the range that is equal to or less than the torque of the motor M corresponding to the lowest optimum carrier frequency. When the torque of M increases, the carrier frequency has a portion that is substantially the same or smaller, and in the range where the torque of the motor M corresponds to the lowest optimum carrier frequency or more, the carrier frequency increases as the torque of the motor M increases. The relationship between the torque of the motor M and the carrier frequency is determined so as to have substantially the same or larger portions.