Abstract
In recent years, automation control system in all a wide range of
applications and development, and dc speed control system as the main way
of electric drive system in one of the modern production plays a very
important role. With the development of the microelectronics, the use of the
computer in speed regulation system simplified the system, reduces the
volume，increases the reliability. The Optimum Control is achieved by the use
of both classical methods and intelligent methods.
The digital speed control system for DC motor, which use Chip
Microcomputer(SCM) as its processor has many merits. The speed giving and
speed measuring adopt digital method, the system can measure the speed
accuracy within a wide range, which expand the speed control scope and
enhances its precession; the hardware is highly integrated, the number of the
parts is sharply minimized; as most functions are carried out by software,
Moreover, as SCM works with digital signal, its control is flexible and its
ability to anti-interference is very high.
The paper is based on the theory of DC speed regulation. In this paper， a
80C196KC SCM is used as the processor for the speed control system of DC
motor. The kind of speed controller is PID and that of current controller is PI.
It is also discussed in this paper how to analyze the math model of double-
close- loop speed control system by analyzing the functions and
characteristics of the speed controlling system for DC motor，and find out the
proportion and integral factors of the current and voltage loop. Moreover，the
system adopted digital speed measuring method to enhance the accuracy of
speed control.
Key words：DC motor; Speed regulation; PID control; Double-closed-loop
