Radio Frequency Interference Considerations in Large-Scale STATCOM Installations

In recent times, applications providing reactive power compensation to the power system have gained interest in the context of Radio Frequency Interference (RFI). A paradigm shift in the converter technology has not only reduced switching losses and given enhanced controllability, but also give rise to concerns about electromagnetic emission. This paper explains the origin of the RFI from a Static Synchronous Compensator (STATCOM), how the emission can be mitigated, and the relationship between emission and the design of the application. In addition, the paper presents necessary measurement and background noise considerations and proves the accuracy of a distance conversion method. The STATCOM is a physically very large application with long conductors, handling high current under high voltages. Comparing to other well-known sources of RFI, the STATCOM differs significantly. This paper explains and concludes why a high-power STATCOM installation cannot follow a small, low voltage and mass-produced, apparatus standard. Far-field theory and presence of high background noise must be considered. The complex nature of the application due to an uncountable number of parasitic inductances and stray capacitances complicates modeling. However, the paper proposes an approach to model standardized major components to yield generic and representative simulation results.