Vol. 62 | nr. 4 | Octombrie - Decembrie 2014 Articolul 8

Comparative Study between Two Topologies of an UPQC Six-Leg and an UPQC Seven-Leg
(full text in English)

Othmane ABDELKHALEK, Abdelrahmane KECHICH, Chellali BENACHIBA
UPQC is the powerful tool to settle the power quality problems. UPQC consist of combined series active power filter (SAPF) that compensates voltage harmonics, voltage sags and voltage swells and parallel active power filter (PAPF) that compensates harmonics current and reactive current. A three-phase four-wire PAPF has also another important function. It’s able to compensate the neutral current when the load is unbalanced. In facts there are two important topologies for this PAPF that the first one consist to connect the neutral wire into the split DC link, however the second one consist to add another leg. In this paper, two UPQC’s topologies are compared. In the UPQC six-leg, the neutral wire is connected into the split DC link. For the UPQC seven-leg the neutral wire is connected into the seventh leg. In addition to well illustrate the difference between these topologies we were test them in two cases. In the first case (Test 1), the load power is supposed lower than the load power in the second case (Test 2). When the power consumed by the load is relatively high, the UPQC seven-leg gives good results compared by the UPQC six-leg.
Keywords: topology, power quality, UPQC, voltage, power system, simulation