DC Motor Speed Control

Speed measuring with a generator or with an encoder via frequency/voltage converter. Speedreference set by means of potentiometer or selector switches and under PLCcontrol. The system has been designed for the study of programmablelogic control techniques in the control of the speed of a separately excited dcmotor. Possibility of acceleration anddeceleration ramps programming. Pointer meters for motor speed, voltage andarmature current connection to PLC through terminals or connectors. The speed regulation includes two control loops: hardware current loopwith over current limiting and speed loop with external PLC control. The PI controller modulates the PWM circuit that drives the powerstage consisting of switching transistor.

Power: 48 Vdc, 5 A.
Power supply: single-phase from mains.
Tachometric signal: 180 V at 3000 rpm.
The student will beable to study the following:
Open loop speed control
Use of the PLC for the speed measuring
Acceleration and deceleration ramps programming
Duty cycle monitoring
Closed loop speed control.