Rapid Harmonic Detection Scheme Based on Expanded Input Observer

The existence of harmonics will cause the quality power supply in a system to decline and affect normal use system. Therefore, it is important suppress system, first step harmonic suppression detection. To address this phenomenon, fast detection method proposed paper. It based on input observer theory construct state space model original signal components estimate variables so as achieve extraction. characteristic roots are used prove convergence observer. In addition, Second-Order Generalized Integration (SOGI) frequency estimation chosen cascade with that can be accomplished unknown frequencies. simulation results quickly converge accurately extract each case fluctuations fundamental amplitude, phase signal, whole process completed 0.02 s. possible effects white noise extraction also simulated, accuracy still guaranteed presence noise. By using Speedgoat real-time target machine built Rapid Control Prototype (RCP) testbed, experiments similar conditions were performed. show has accurate performance.