Demand Response Mismatch (DRM): Concept, Impact Analysis, and Solution

Demand response (DR) is emerging as one of the key smart grid components that plays a major role in achieving adequate supply-demand balance. DR is often considered as a market resource and thus there is more focus in the literature on economic aspects, thereby neglecting the DR's interaction and impact on the power system operation. This paper identifies a potential gap while employing DR in distribution systems. Usually, the load reactive power and the load's voltage dependency are ignored in the DR studies. It is shown in this paper that the inclusion of these two elements results in an active power mismatch between the scheduled and the actually achieved DR. A new term that is capable of quantifying this mismatch is introduced and is termed as demand responsemismatch (DRM). To overcome such problem, this paper proposes a mixed integer non linear program (MINLP) to find the optimal size and location of STATCOM and/or optimal transformer tap setting that can minimize the DRM. The phenomenon of DRM is illustrated using a standard 16-bus U.K. generic distribution system (UKGDS) while considering different load power factors, load reduction amounts, load models, as well as DR locations.