Several HVDC–MMC link [1] projects are currently planned or
constructed by RTE (French TSO). One of such projects is the INELFE
interconnection project, with a capacity of 2000 MW [2], between
France and Spain. HVDC link interconnections in France are part of
a highly meshed ac network. This is a relatively new aspect. Such
links may have abnormal interaction risks and also impact on the
performance of the ac network. In [3–5], small-signal analysis of
VSC stations and modal studies of a dc grid were presented. In
[6], a stability study between two HVDC links and a comparison
between VSC and LCC are contributed. Studies on a VSC–HVDC link
connected in parallel with an ac line are available in [7,8]. In [9], a
study of interaction between a VSC–HVDC link and a STATCOM is
presented.
In this paper, modal analysis and EMT-type methods are used to
study interactions between HVDC links connected in parallel with
an ac line. Therefore, unlike previous articles, it provides a complete
overview on the abnormal interactions that can occur during small
and large disturbances.
There are different simulation tools for assessing the stability of
electrical networks. EMT-type simulations are used to evaluate the
response of the system subjected to major disturbances. The
models required for this type of simulation must be accurate to