FFT Harmonics Analysis
Harmonics are integer multiples of the fundamental frequency (e.g. 50 Hz) and cause a distortion in voltage and current of the original waveform. Harmonic voltages and currents caused by non-sinusoidal loads can affect the operation and lifetime of electrical equipment and devices.
Harmonic frequencies in motors and generators can lead to increased heating (iron & copper losses), can affect torque (pulsating or reduced torque), create mechanical oscillations, and higher audible noise, which can cause aging of shaft, insulation, and mechanical parts and reduce the efficiency.
Current harmonics in transformers increase copper and stray flux losses. Voltage harmonics increase iron losses. The losses are directly proportional to the frequency and, therefore, higher frequency harmonic components are more important than lower frequency components. Harmonics can also cause vibrations and higher noise. The effects of other electrical equipment and devices are very similar and are mainly reduced efficiency and lifetime, increased heating, malfunction or even unpredictable behavior.
Harmonics, Interharmonics and THD
The Dewesoft solution can measure harmonics for voltage, current and additional active and reactive power up to the 3000th order. All calculations are implemented according to IEC 61000-4-7 standards.
You can define the number of sidebands and half-bands for the harmonic order calculation. The higher frequency parts can be grouped in 200 Hz bands up to 150 kHz.
The calculation of THD (overall harmonic content) for voltage and current up to 3000th order and the interharmonics complete the analysis functionalities.
These powerful harmonic calculation functions offer analysis for all types of electrical equipment and devices.
Harmonics calculations
U, I, P, Q, and impedance
Individual setup of the number of harmonics including DC component (Example: 20 kHz sampling rate = 200 harmonics @ 50 Hz)
Harmonics up to 3000th order (@50 Hz)
Variable sidebands and half sidebands for Harmonics
Higher Frequencies up to 150 kHz in 200 Hz bands
Interharmonics, groups or single values
According to EN 61000-4-7
Calculation corrected to the actual real frequency
THD, THD even, THD odd
Trigger on each parameter
Background harmonics substraction