FAST AND PREDICTIVE HVDC EXTINCTION ANGLE CONTROL

This paper proposes unique de control strategies to prevent dynamic co mmutation failures during and following faults, and to obtain better r ecovery from the faults. The strategy is based on an idea of sine-cosi ne components detector in which as voltages are detected fast in terms of two components on the rotational reference frame synchronized with an ac system frequency. The controller quickly predicts a necessary c ontrol angle according to the magnitude, the phase angle, and involved harmonics that ape calculated from these two components. The validity and effectiveness of the controller are confirmed through the EMTP si mulations, The de simulator results using bite fabricated controller c onfirm the EMTP simulations.