04-01-2013, 04:54 PM
Microcontroller-based DC Motor Controller
1Microcontroller-based DC.pdf (Size: 666.93 KB / Downloads: 103)
Motion control plays a vital role in industrial automation.Manufacturing plants in industries like chemical, pharmaceutical, plastic and textile, all require motion control. And it may be a flatbelt application, flow-control application or mixing of substances. Different types of motors—AC, DC, servo or stepper—are used dependingupon the application. Of these, DC motors are widely u sed because controlling a DC motor is somewhat
easier than other kinds of motors. The motion of a DC motor is controlled using a DC drive. DC drive changes the speed and direction of motion of the motor. Some of the DC drives are just a rectifier with a series resistor that converts standard AC supply into DC and gives it to the motor through a switch anda series resistor to change he speed and direction of rotation of the motor. But many of the DC drives have an inbuilt microcontroller that provides programmable facilities, message display on LCD, precise control and also protection for motors. Using the DC drive you can program the motion of the motor, i.e., how it should rotate. Here are some of the features of this DC motor controller:
1. Controlled through microcontroller AT89C51
2. Message displayed on the LCD module
Circuit description
Fig. 1 shows the circuit of the microcontroller- based DC motor controller. At the heart of the DC motor controller is microcontroller AT89C51. Port pins P0.0 through P0.7 of the microcontroller are interfaced with data pins D0 through D7 of the LCD module, respectively. Port pins P3.0, P3.1 and P3.2 control the LCD operation through enable (E), register-select (RS) and read/write (R/ W) pins, respectively. Contrast of the LCD is set by preset VR1. Port pins P1.0 through P1.7 are connected to switches S1 through S8 for performing the various operations.