A Specific Harmonic Detection Method for Three-Phase Four-Wire Circuits Based on Multi-frequency Rotating Coordinate Transformation

The detection of harmonics is an important foundation for analysis and control of harmonics of power systems. This paper puts forward a new harmonic detection method based on a rotating coordinate transformation of multi-frequency, and expatiates of the basic theory of rotating coordinate orthogonal transformation of multi-frequency and its actualization processes to detect harmonics. Finally, computer simulation of harmonic detection based the proposed method and simulative results are given. The proposed detection method can detect the instantaneous values of random harmonic components and random fundamental components in real time with none principle error, and has the characteristics of high detection precision, good real time and simple actualization.