How to reverse dc motor controller

For use in dc motor controller, sometimes needs to be reversed, so how to proceed with reverse? Below small make up for it. Usually the reversal of the dc motor controller is divided into two kinds: 1. To reverse connection through the armature voltage on both ends, and then make the armature current direction change. 2. Through the study of the change of the polarity of the excitation winding, so as to make the main direction of the magnetic field change. Through professional one of the above mentioned methods can realize the reversal of the dc motor controller, but if the two methods used at the same time, it was no motor to reverse.