Impact of dynamic system modelling on the power stability of HVDC systems

Common industry practice assumes certain quasistatic conditions to determine the power stability of HVDC systems. Particularly, a constant Thevenin AC voltage source has become a de facto industry assumption. This work presents a dynamic approach to study the power stability of HVDC systems. Based on this approach, the impact of dynamic system modelling on the power stability limit of HVDC systems is examined. Consequently this provides an insight into whether the quasistatic assumptions are justified. The qualitative and quantitative impact of system dynamics and associated parameters, respectively, on the quasi-static maximum power curve are shown. These are shown using dynamic time-simulations and mathematical analysis, the close correspondence between their results also mutually verify the two approaches