Analysis of the effects of a high power electronics controller on electrical Grids during faulted and post-faulted conditions using wavelets

FACTS controllers and HVDC links are high power electronics-based structures which have shown its strength in improving the operation and control of nowadays electrical networks worldwide. Alongside the many benefits they provide, there are also collateral effects on the grid as consequence of dynamically deviating localized network parameters, which affects the protection system for instance. This paper reviews some effects of the STATCOM, TCSC and UPFC on equivalent parameters of the grid on faulted and non-faulted conditions. As main point, this paper also analyses the dynamic effects of the TCSC on the equivalent reactance of the neighborhood of the controller in the transit from pre-faulted to faulted condition. The steady state waveforms and those from the transient oscillations emerged during the faulted state are processed using wavelets to determinate effective protection and control actions. The results presented have been obtained by combining the capabilities of PSCAD and MATLAB-Simulink.