At first, motor speed is transferred to PLC by shaft encoder, then PLC according to the program and PID controller generate the control signal to reach the desired speed. The analog signal from the D/A module is transmitted to the DC drive.
Can a PLC control DC motor?
A simplified approach for speed control of a DC motor using programmable logic controller (PLC) is presented. This approach is based on providing a variable dc voltage to armature circuit of dc motor from a fixed dc supply voltage via a PLC for supply voltage control method.
How is an SCR used to control the speed of a DC motor?
The o/p of SCR rectifier can be control by controlling the gate current of SCR. So, this way the SCR can operate at different levels of conduction and apply varies voltages to the motor armature, this way the speed of DC motor can control.
How does DC drive control speed?
DC drives are DC motor speed control systems. Since the speed of a DC motor is directly proportional to armature voltage and inversely proportional to motor flux (which is a function of field current), either armature voltage or field current can be used to control speed.
How does a PLC control a motor?
A PLC has to start a Motor when the Start button is pressed. It has three interlocks which are Motor Vibration High, Overload & Motor Temperature High. if any of the interlock activated then PLC has to stop the motor immediately. PLC has to stop the motor if the stop button is pressed.
How does PWM control speed of DC motor?
As its name suggests, pulse width modulation speed control works by driving the motor with a series of “ON-OFF” pulses and varying the duty cycle, the fraction of time that the output voltage is “ON” compared to when it is “OFF”, of the pulses while keeping the frequency constant.
Which signal will control the speed of DC motor in a microcontroller 8051?
This is a simple project/tutorial on how to control Dc motor speed using 8051(89c51,89c52) microcontroller? Dc motor or fan speed is controlled using Pwm(Pulse width Modulation) technique. Their are two ways to generate pulse width modulation signal using 8051(89c51,89c52) microcontrollers.
How can we change speed of DC motor using PWM?
If such a signal is fed to a DC motor, we can change the speed of the motor by changing the duty cycle of the PWM signal. The change in pulse width is created by increasing the on-time (HIGH value) of the pulse while reducing the off-time (LOW value) by the same amount so that the frequency of the signal is constant.
What are the methods of speed control of DC motor?
Thus, the speed of a DC motor can control in three ways:
- By varying the flux, and by varying the current through field winding.
- By varying the armature voltage, and the armature resistance.
- Through the supply voltage.
What is an SCR speed controller?
An SCR (Silicon Controlled Rectifier) is a controllable medium- to high-power self-latching solid-state DC power switch.
How does a SCR controller work?
SCR power controllers compensate for mains voltage fluctuations by employing RMS voltage regulation. An SCR’s voltage regulation mode adjusts the firing angle (phase angle) or duty cycle (zero cross) of the SCR output to maintain a constant voltage output proportional to the set point.
How does a DC drive control motor?
DC drive is basically a DC motor speed control system that supplies the voltage to the motor to operate at desired speed. … By using an induction motor, the DC generator was driven at a fixed speed and by varying the field of the generator, variable voltage was generated.
How does a DC drive control a DC motor?
In general, a DC drive converts an Alternating Current (AC) into Direct Current (DC) to run a DC motor. … Applying the voltage to the gate at a different angle of the input phase, the output current varies and thus the drive can control the motor speed.
How is motor speed controlled?
Thus, the speed of a DC motor can be controlled in three ways: By varying the supply voltage. By varying the flux, and by varying the current through the field winding. By varying the armature voltage, and by varying the armature resistance.