A system which can control and regulate the speed of a separately excited CD motor has been constructed in a way such that a wide range of speed from standstill up to 130% of rated speed can be controlled, and extra starting torque can be obtained. This incorporates both armature voltage control and field weakening control to provide smooth and precise action. The system is administered by computer programs which operate in three modes of operations in a consecutive manner, as explained below: - Starting mode operation: during this mode, the system starts the motor overcoming the starting torque. This mode continues until the speed attains 10% of its rated value. - Dynamic mode operation: this mode is activated in order to control the normal operation. This is achieved by regulating the system against any load disturbances. This function is performed through the action of the PI controller associated with the armature driver. - Over speed mode: in this mode the field current drive is the active unit used to obtained and regulate speeds higher than rated speed. To avoid undesirable interference effects between controllers, only one controller is activated at any instant Software simulating the experimental system in its three modes has been built and tested. Theoretical results obtained from software simulation are in fairly close agreement with the experimental results.