DC Motor Speed Control-An Integral Part of Its Working

Speed control means a change in the working speed to a point which is needed ideally. It is different from speed regulation because in regulation the change is natural and in control, there is an external force at work. Speed control can be either manually done by a person operating the motor or it can be controlled automatically.

In the case of a series motor, either armature control or field control can be used for DC motor speed control.

Armature Control for DC Motor Speed Control

There are three methods of armature control by which DC motor speed control can be achieved.

Armature resistance control method is the most common of the methods. In this method, the controlling resistance is connected in series with the supply to the motor. There is a certain amount of power loss in this but it can be ignored because this method is mostly used to reduce the speed under conditions of light load. The uses of this method are in cranes, trains and hoists.

he shunted armature control method uses two rheostats, with one shunting the armature and the other in series with the armature. The speed control in this method is over a varied range, below normal speeds but it is not considered very economical.Armature terminal voltage control method uses a variable voltage supply to supply the power to the motor and control the speed of the motor. This method is extremely expensive and so it is hardly used.

As you can see, there are quite a few methods for DC motor speed control. Buying any motor can be a process which takes a bit of effort and know-how. Teco Electric Co. Ltd. focuses on manufacturing electric motors of all kinds so you do not have to look anyplace else.