  A grid-feeding converter system is added to a novel power system transient
simulation scheme based on frequency response optimized integrators considering
second order derivative. The converter system and its implementation in the
simulation scheme are detailed. Case studies verify the accuracy and efficiency
of the simulation scheme. Furthermore, this paper proposes and justifies
extending the simulation scheme by integrating commonly used numerical
integrators considering first order derivative for part of the studied system.
The proposed extension has an insignificant impact on the accuracy of the
simulation scheme while significantly enhancing its efficiency. It also reduces
the development burden in adding new devices.

Systems and Control;Systems and Control