Abstract：Line commutated capacitor high-voltage direct current（ LCC-HVDC）is an important technical

form of high-voltage direct current transmission. Since the converter valve was composed of semi-controlled device

thyristors，the commutation failure of the inverter-side converter station has become a key issue affecting the

normal and safe operation of LCC. Configuring static var generator（SVG）for reactive power compensation can

effectively improve the converter station's ability to resist commutation failure. The influence of SVG reactive

power compensation was discussed on LCC commutation failure from a mechanism perspective，and simulation

verification was conducted. First，the mathematical model of LCC was established and the mechanism of

commutation failure was analyzed. Secondly，the influence of SVG reactive power compensation on the

commutation failure process was analyzed. Finally，the model was built in Simulink for simulation verification.

      Key words：line commutated capacitor high-voltage direct current（LCC-HVDC）；commutation failure；

reactive power compensation；static var generator （SVG）