Full current harmonic detection method based on sinusoidal amplifier

There are many links and complex structures in the ip-iq method which based on instantaneous reactive power theory. At the same time, the rapidity of harmonic detection is affected by the existence of low pass filter (LPF). On this basis, in order to accurately and quickly detect the harmonic current of the grid, this paper presents a full-current harmonic detection method based on Sinusoidal Amplitude Integrator (SAI). In this method, the calculation of active current and reactive current is eliminated on the basis of ip-iq harmonic detection method and the positive sequence fundamental wave extraction structure of SAI replaces the LPF. The harmonic command current is calculated by the extracted positive sequence fundamental current, in order to compensate the grid. The simulation and experiment of the proposed method are carried out under the balanced grid. Finally, the feasibility and validity of the method are verified. © 2020, Solar Energy Periodical Office Co., Ltd. All right reserved.