Study of two detection methods for harmonics and reactive currents

To the requirements of the detection of harmonics and reactive currents of active power filter (APF), two detection methods of single-phase circuit are studied and the two detecting schematics are also given. The former is the detection method based on the character of triangle function and some improvements are done; The latter is the detection method based on the theory of adaptive linear neural network. Theoretical analysis and simulation results show that both methods can real time detect the instantaneous harmonics and reactive currents in single-phase circuit, and the improved method based on the character of triangle function is more simple. The waveform of simulation confirmed the effectiveness of the two methods.