Research Of ARM-Based Digital Control System For DC Motor

Direct Current (DC) motor has good starting capability, control capability and overload capability, so that it is widely used in many different industrial fields. To control DC motor means to control its speed, moment of force and the position.Because of the fast development of the science and technology, especially the fast development of the computer science, micro electronic technology and the advanced control theory, the control of DC motor also has developed a lot. More and more digital control systems have replaced the traditional analog control systems, and the controller becomes more and more intelligent. The main point of this project is to research the digital control system of DC motor.The control system, talked in this dissertation, used silicon-control rectifier (SCR) to control the speed and the current of the DC motor. The main chip of this control system is an ARM7 series micro controller unit - LPC2132, with it, we can trigger the silicon-control in digital way. This system adjusts the speed-current double closed loop by PID control theory to make the DC motor work regularly. On the other hand, to widen the use range of this control system, this dissertation talked about some research on the PID parameters automotive tuning theory.The main content of this dissertation is as below:1. Introduced the history and the tendency of the DC motor and the control methods of DC motor; compared several recent control methods of DC motor; introduced the main chip of the controller system.2. According to capability of the circuit of DC motor, build the model of DC motor; designed the speed-current double closed loop system based on the model of DC motor; analyzed the method to solve the problem of discontinuousness of current.3. Allotted the inside hardware resource of LPC2132; designed the circuits of this control system.4. Designed the software part of this control system.5. Researched the control theory, controlled the speed loop and current loop by PID control theory; did some research of PID parameters automotive tuning of the current loop.6. Motor speed control experiment.