Patent ID: 8669724
Filing Date: 2014-03-11
Classification: H02P

Abstract:
1. A motor drive for controlling rotation of a motor in a material handling system, comprising: an input configured to receive a command signal from a controller, wherein he controller is manually manipulated by an operator to generate the command signal; a memory device storing a series of processor executable instructions; and a processor in communication with the memory device, wherein the processor is configured to execute the instructions to: control the motor to rotate at a speed command responsive to the command signal; when the motor is rotating, periodically obtain a signal corresponding to a magnitude of torque produced by the motor and determine a maximum operating speed of the motor as a function of the magnitude of torque produced in the motor, when the maximum operating speed is greater than the speed command, increase the speed command to the maximum operating speed, and when the maximum operating speed is less than the speed command, decrease the speed command to the maximum operating speed.