Unified power quality conditioner based on current source converter topology
Nonlinear devices, such as power electronics converters, inject harmonic currents in the AC system and increase overall reactive power demanded by the equivalent load. Also, the number of sensitive loads that require ideal sinusoidal supply voltages for their proper operation has increased. In order to keep power quality under limits proposed by standards, it is necessary to include some sort of compensation. Different types of power quality compensators of higher or lower complexity have been reported. The aim of this paper is to present a unified power quality conditioner (UPQC) that consists of two three-phase current-source converters connected on the same inductive DC link. Such system has faster phase voltage control loop than its voltage-source converter based counterpart, as well as the inherent short circuit protection capability. Also, in this case passive filter connection between UPQC and the load is not needed, which minimizes the cost of the system.