Comparative Analysis of Radiated Interferences and Conducted Interferences Generated from a SVC

Static var compensator (SVC) devices have an increasingly extensive application in modern substations to achieve voltage stability. While, due to frequent switching of the thyristors, large amount of electromagnetic interferences (EMI) are generated, which can cause malfunction of SVC or unaccepted response of victim devices positioned nearby. An advanced acquisition system is established to implement on-site measurement so as to obtain the EMI data. The switching bursts of the radiated and conducted EMI data within a power cycle are comparatively analyzed in both time- and frequency-domains so as to give the frequency and amplitude range of the EMI data in details. Further, with utilization of time-frequency analysis techniques, such as short-time Fourier transform, Wigner-Ville distribution and smoothed pseudo Wigner-Ville distribution, more detailed and useful information of the SVC-based electromagnetic environment can be obtained through 2-D and 3D display, which presents valuable reference for effectively evaluating the EMI levels of SVC devices.