On the phase voltage monotonie property in unbalanced distribution networks

Abstract

The notion that phase voltage magnitudes decrease as loads increase is widely accepted. In this paper, however, two counter examples are presented to show that this notion does not generally hold. The sufficient conditions, under which phase voltage magnitudes of one bus and those of its neighboring buses monotonically decrease with local active and reactive power injections, are given in close form. Intuitive analysis show that the proposed sufficient conditions typically hold in practical networks. The derived monotonic property is illustrated via numerical tests on a 14-bus test system and an IEEE 8,500-node power network. Some potential applications are further discussed.