A Spectrum Correction Approach for Power System Sub-harmonic Analysis

Parameters identification of power system inter-harmonic is research emphasis recently, because it can be seriously interfered by nearby harmonic leakage. The sub-harmonic lower than power frequency is not only disturbed by power frequency component, but also interfered by negative frequency component itself. A variety of analytical methods are used for acquiring the parameters of the signal but difficult to eliminate various confounding factors adequately. Therefore, as sub-harmonic component can be interfered by both negative frequency component and power frequency component, an improved low frequency spectrum correction model was established, and different frequencies of sub-harmonics were analyzed with scanning way. Simulation results show that the proposed method for identification of sub-harmonic parameters has higher accuracy, small computation and is easy for project implementation.