Common Errors in FFT Analysis due to Inadequate Period Usage: Introducing the VFID Method as Solution Method

Accurate modeling of variable frequency distributed generation (DG) systems is essential for understanding their behavior and optimizing performance. Conventional methods often struggle to capture individual ripple information, hindering accurate representation of variable frequency systems. This paper introduces the variable frequency interharmonic domain (VFID) method as a solution to common errors encountered with traditional methods, such as spectral leakage and aliasing introduced by the fast Fourier transform (FFT) algorithm. VFID offers precise ripple information without the need for additional post-processing routines, ensuring robust analysis of variable frequency DG systems. By mitigating errors associated with FFT analysis, VFID enhances the accuracy and reliability of frequency domain representations, leading to improved system design and operation in power quality analysis applications.