ANALYSIS OF POWER PHENOMENON AND CLASSIFICATION OF REACTIVE POWER IN THREE-PHASE CIRCUIT
WANG Mao-hai ,SUN Yuan-zhang (Department of Electrical Engineering, Tsinghua University, Beijing 100084, China)
Detailed physical analysis of power phenomenon in three-phase circuit is given. It verifies that the total three phase instantaneous power cannot remain constant in circuits with distort and unbalanced source. This conclusion gives a further physical explanation of the active current defined by the universal instantaneous power theory (UIPT). This paper also points out: in nonsinusoidal and unbalanced circuit, there are not only reactive power flowing among phases, but also reactive power flowing between 3-phase source and 3-phase load. Proceeding from minimum transmission loss criterion, this paper presents the definition of reactive power flowing among phases and reactive power flowing between 3-phase source and 3-phase load. Active current, reactive current flowing among different phases and reactive current flowing between source and load have a pairwise orthogonal relationship in the framework of UIPT. If the reactive power flowing between source and load is ignored, the UIPT is identical with H.Akagi抯 reactive power theory.
【CateGory Index】： TM714