Advantages and disadvantages of pulse width modulation (PWM)
Pulse width modulation (PWM) is a technique used to reduce the power of the signal by converting that into small elementary parts of the signal, this is done by one part of the input to the comparator, while the non-sinusoidal wave or saw tooth waveforms the other parts of the input, then the comparator compare two signals to generate PMW signal as the output waveform.
Advantages of pulse width modulation (PWM)
- The power loss in the switching device is very low.
- Cheap to make
- Low power consumption
- Efficiency is up to 90%
- Signal separation is an easy process with demodulation.
- Noise cancellation is easy
- High power handling capacity
- It utilizes high-frequency values
- Noise interference is less
- Energy efficient
- Synchronization between transmitter and receiver is not required.
- Less filter requirement
- The amplitude and frequency of the signal can be controlled independently.
- They avoid any waveform distortion
- Large bandwidth
- The switching speed regulates the flow of current.
- No losses
- We can easily control analog load using a digital signal.
- We can operate a device above its normal maximum.
- The accuracy of the device is good.
- This method increases speed control and reduces power losses.
- Internal motor resistance can be easily overcome.
- The PWM is moderate in complexity to implement.
- Compact in size
- Less maintenance
- They had accurate and fast response times.
- They had a high input power factor.
- They support the motor to generate maximum torque.
- PMW system had the digital form of processors and controlling system.
- The digital operation enhances noise resistance.
Explanation for advantages of pulse width modulation (PWM)
Low power dissipation/efficiency
The pulse width modulation (PWM) works by generating or supplying a fixed voltage power supply to the device for switching ON and OFF conditions continuously, thereby this reduces the overall energy towards the device.
This whole operation lowers the power dissipation at the pulse width modulation (PWM), which results in higher efficiency at them.
Demodulation
The signal from the PWM passes towards the pulse amplitude modulation (PAM), this will convert PWM to PAM signal and then passes to the low pass filter for signal separation.
Noise cancellation
The pulse width modulation (PWM) reduces its noise by reducing slew rate, which is the change of voltage or current per unit time, this is been done at the device.
Higher frequency
The PWM had higher frequency values, for the applications like motor driving or controlling, the frequency of the pulse width modulation technique is utilized.
Response time
The motor driving applications like servo motor controlling, the response time is an important value to consider, at PWM is always between 1ms and 2ms.
Disadvantages of pulse width modulation (PWM)
- Complexity of circuit
- Voltage spikes will be acquired
- Radio frequency interference
- Electromagnetic noise
- Bandwidth should be large to use in communication
- High switching losses due to high frequency
- Instantaneous power of the transmitter is varies
- The system required a semiconductor device with low turn ON and turn OFF times.
Explanations for disadvantages of pulse width modulation (PWM)
Complexity of the circuit
The pulse width modulation (PWM) circuit is a complex network, this is because the PWM technique uses precise control of analog devices with the digital signal.
PWM interference
The pulse width modulation (PWM) method had high current, high frequency PWM signals are notorious for creating and radiating electromagnetic interferences.
When we use PWM at power-controlling devices, we need to make a connection that will minimize the effect of radiation on the circuit.
