5th Harmonic & Induction Motor Simulation
Explore how the 5th harmonic can create torque pulsation, heating and mechanical vibration.
⚡ Electrical Supply
5th Harmonic: 0% of fundamental🛠 Harmonic Mitigation
Select one or more methods and observe the improvement.
Voltage Waveform
Motor Response
Torque Pulsation
0%
Motor Heating
Low
Vibration
Low
Harmonic Stress
Low
Normal sinusoidal supply — low harmonic stress
What is the 5th harmonic?
The 5th harmonic is a sinusoidal component whose frequency is 5 times the fundamental frequency. For a 50 Hz system, the 5th harmonic is 250 Hz. In a three-phase induction motor, the 5th harmonic is a negative-sequence harmonic. Its rotating magnetic field travels in the direction opposite to the fundamental field.
Why can it produce torque pulsation?
The interaction between the fundamental magnetic field and harmonic fields can produce additional oscillating torque components. These torque variations can contribute to mechanical vibration, acoustic noise and additional losses. The harmonic currents also increase motor losses, which can raise winding and core temperatures.
The 5th harmonic is a sinusoidal component whose frequency is 5 times the fundamental frequency. For a 50 Hz system, the 5th harmonic is 250 Hz. In a three-phase induction motor, the 5th harmonic is a negative-sequence harmonic. Its rotating magnetic field travels in the direction opposite to the fundamental field.
Why can it produce torque pulsation?
The interaction between the fundamental magnetic field and harmonic fields can produce additional oscillating torque components. These torque variations can contribute to mechanical vibration, acoustic noise and additional losses. The harmonic currents also increase motor losses, which can raise winding and core temperatures.
How to Reduce 5th Harmonic Problems
1. Harmonic Filter
Passive or active filters can reduce harmonic current and voltage distortion before it reaches the motor.
Passive or active filters can reduce harmonic current and voltage distortion before it reaches the motor.
2. Low-Harmonic VFD
Select a VFD with low harmonic input current or an active-front-end design where appropriate.
Select a VFD with low harmonic input current or an active-front-end design where appropriate.
3. Line Reactor
An input reactor can reduce current distortion and limit the severity of harmonic currents produced by power-electronic loads.
An input reactor can reduce current distortion and limit the severity of harmonic currents produced by power-electronic loads.
4. Good System Design
Correct motor sizing, balanced phases, suitable cabling and proper VFD parameters help reduce additional motor stress.
Correct motor sizing, balanced phases, suitable cabling and proper VFD parameters help reduce additional motor stress.