Methods and apparatus are provided for preventing a voltage overload condition of an alternating current (“AC”) motor electrically coupled to an inverter. In an embodiment, the system includes an oil pump, a motor in communication with the oil pump, an inverter module in electrical communication with the motor, the inverter module configured to generate a speed command, and a controller module. The controller module is in communication with the inverter module and the motor and is configured to determine an error, based, in part, on an estimated torque value of the motor and a predetermined maximum available torque value, to convert the error into a first value, to limit the first value between a negative value and zero, and to add the first value to the speed command from the inverter to thereby generate a final speed command for the motor.