Digital control for brush DC motor

In home appliances applications the brush DC motor, driven by a chopper, can be controlled by a standard microcontroller. However people often consider the microcontrollers as not suitable for the power environment because of their limited computing speed or noise immunity problems. This paper shows how a cost effective digital motor drive can be designed by combining a chopper and an 8 bits microcontroller: the speed is simply controlled through direct voltage compensation and motor power limitation. The microcontroller implements both motor control and interface functions of the application: it replaces the analog circuits of the conventional motor control. Performances and practical results are given for a 300 W/12000 RPM motor drive