Frequency domain model of an HVDC link with a line-commutated current-source converter. part II: varying overlap

The second part of the description of a frequency-domain model of a high-voltage direct current (HVDC) transmission link with line-commutated current-source converters is presented in this study. The model is based on transfer functions between superimposed oscillations in the control signal and the AC- and DC-side voltages and currents. In dasiaPart Idasia of the description the overlap angle was assumed to be constant. At certain resonance frequencies severe deviations were obtained between the calculated transfer functions and the ones extracted from time-domain simulations. In this study (Part II), the model has been extended to deal with varying overlap angle. It is shown that the agreement between transfer functions calculated in frequency- and time-domain has improved substantially.