A harmonic and inter-harmonic parameter estimation algorithm of electric power systems based on tri-linear decomposition

With a large number of nonlinear loads integration into the electric power grid, pollution of harmonic and inter-harmonic have become more and more serious. In order to improve the effectiveness of harmonic elimination and ensure the security, reliability and stability of electric power system, an algorithm of harmonic and inter-harmonic parameter estimation based on tri-linear decomposition was proposed. The frequency signal with harmonic and inter-harmonic can be analyzed by transforming the signal to spatial signal with the use of Euler formula. A tri-linear characterized signal model was constructed by using multiple delay output of the receiver. Complex parallel factor (COMFAC) algorithm was used to complete tri-linear fitting. The simulation results reveal that this algorithm not only can recognize the fixed frequency, but also can track the dynamic one. At the same time, it can realize estimation of amplitude and phase. And it is a super resolution algorithm of harmonic and inter-harmonic parameter estimation. © 2013 Chinese Society for Electrical Engineering.