  Throughout the past few years, various transmission system operators (TSOs)
and research institutes have defined several functional specifications for
grid-forming (GFM) converters via grid codes, white papers, and technical
documents. These institutes and organisations also proposed testing
requirements for general inverter-based resources (IBRs) and specific GFM
converters. This paper initially reviews functional specifications and testing
requirements from several sources to create an understanding of GFM
capabilities in general. Furthermore, it proposes an outlook of the defined GFM
capabilities, functional specifications, and testing requirements for offshore
wind power plant (OF WPP) applications from an original equipment manufacturer
(OEM) perspective. Finally, this paper briefly establishes the relevance of new
testing methodologies for equipment-level certification and model validation,
focusing on GFM functional specifications.
