This paper arrives at a method of harmonic and reactive current real-time detection applied on active power filter based on the three-phase circuit instantaneous reactive power theory. With Matlab simulation software, a research on simulation of harmonic detection means is carried out, and an analysis of the simulation result is presented. The result indicates: the harmonic detection means based on instantaneous reactive power theory can detect harmonic and reactive component in three-phase current precisely and real-time, to supply reliable harmonic and reactive current for harmonic restraint and reactive power compensation. It could provide reliable indicator parameters for research and development of active power filter.
