Secant Method Applied to Control of HVDC in the Harmonic Domain

This paper presents a harmonic domain (HD) model of a high-voltage direct current (HVDC) system including controls for DC voltage and reactive power via the secant method. The proportional-integral (PI) control scheme is used to verify the results by the secant method. It is shown that the latter achieves computational savings compared to the PI control scheme. A case study is presented and verified with the PSCAD/EMTDC software tool in terms of harmonics and steady state waveforms.