An Amplitude Adaptive Notch Filter for Grid Signal Processing

This letter presents an amplitude adaptive notch filtering (AANF) as a tool for grid signal processing and synchronization of distributed generation systems that provide improvement solutions for both grid-connected and stand-alone mode of microgrids. The proposed technique is simple and offers a high degree of immunity and insensitivity to power disturbances, especially when the signal amplitude varies. Since the powerful technique can reduce impact of the amplitude variation of signal, it has a wider range of application and can take the place of the traditional ANF in the microgrids. This technique can also be used in the detection of symmetrical components, harmonics, active power, and reactive power. Theoretical analysis is presented and the performance of the method is evaluated by simulation.