A methodology to study the impact of an increasingly nonconventional load mix on primary frequency control

The last three decades have experienced an impressive growth in loads interfacing with the grid through power electronic devices. These include personal computers and most office equipment as well as industrial induction motors driven by variable frequency drives. The increasing importance of these non-conventional loads has an impact which is yet to be quantified and modeled systematically. This is particularly the case with the natural load-side frequency response, and this lack of knowledge compounds with the current uncertainty in the characterization of the load's natural behavior under frequency disturbances. This paper provides a research roadmap to address this question in a rigorous manner. We propose a bottom-up modeling approach which should provide a deeper understanding of this impact and inform on the way power systems operate under a highly nonconventional load mix during transient frequency events.