Patent ID: 9246430
Filing Date: 2016-01-26
CPC Classification: H02P

Claim Text:
1. A method for controlling an inverter that supplies power to a motor, the method performed by a controller and comprising: determining if the motor is in a manual mode; calculating an optimal speed; determining a final speed as the optimal speed both when a command speed is higher than a rated speed level of the motor and when the motor is not in the manual mode and the command speed is lower than or equal to both the rated speed level and a predetermined optimal speed level; determining the final speed as the command speed both when the motor is in the manual mode and the command speed is lower than or equal to both the rated speed level and the predetermined optimal speed level and when the command speed is lower than or equal to the rated speed level and higher than the predetermined optimal speed level; and supplying the determined final speed to the inverter, wherein calculating the optimal speed comprises: setting a torque limit; accumulating torques during a set time; calculating an average of the accumulated torques; and calculating the optimal speed using the set torque limit, the calculated average of the accumulated torques and the rated speed level.