Electric motor control

A motor control device, comprising:

• a controller connected to an electric motor of a vehicle, the controller configured to:
• monitor torque command signals from a vehicle system to the electric motor, each torque command signal configured to cause the electric motor to output a commanded torque;
• monitor a speed of the vehicle and an output torque of the electric motor, the output torque responsive to a drive signal generated based on the torque command signals;
• and
• based on the output torque and the vehicle speed indicating a low motor efficiency condition, modulate the drive signal between a first torque value and a second torque value that is less than the first torque value, the first torque value greater than the commanded torque and selected to increase an efficiency of the electric motor.

A vehicle system comprising:

• a memory having computer readable instructions;
• and
• a processing device for executing the computer readable instructions, the computer readable instructions controlling the processing device to perform a method including:
• monitoring torque command signals to an electric motor of a vehicle, each torque command signal configured to cause the electric motor to output a commanded torque;
• monitoring a speed of the vehicle and an output torque of the electric motor, the output torque responsive to a drive signal generated based on the torque command signals;
• and
• based on the output torque and the vehicle speed indicating a low motor efficiency condition, modulating the drive signal between a first torque value and a second torque value that is less than the first torque value, the first torque value greater than the commanded torque and selected to increase an efficiency of the electric motor.