Simulate PWM Using Labview Softwere

PWM

• Pulse Width Modulation (PWM) used in this process to control the speed of the motor by varying the duty cycle of the PWM. In this system, 0% duty cycle produce 0V of output voltage which means the PWM is in fully-off state while 100% duty cycle produces 5V of output voltage which means the PWM is in fully-on state.
  

• The variable output voltage which denoted here as Controlled Voltage (Vc) is used for variable input voltage to the motor which give variable speed to the motor which depends on the input voltage.

Pulse width modulation ( Final Control Element)

• Pulse width modulation (PWM) is a technique to control the DC motor speed which is a series of digital pulses is used to control an analog circuit. The length and frequency of these pulses determines the total power delivered to the circuit.  The digital pulse train that makes up a PWM signal has a fixed frequency and varies the pulse width to alter the average power of the signal. The ratio of the pulse width to the period is referred to as the duty cycle of the signal.  Figure below is the waveform of PWM in 40% until 100% of duty cycle.