Delivering clean and pure power

There are two approaches to the mitigation of power quality problems. The first approach is called load conditioning, which ensures that the equipment is made less sensitive to power disturbances, allowing the operation even under significant voltage distortion. The other solution is to install lineconditioning systems that suppress or counteract the power system disturbances. Among the different new technical options available to improve power quality, active power filters have proved to be an important and flexible alternative to compensate for current and voltage disturbances in power distribution systems. Power filter topologies are discussed including shunt active filter, series active filters, series-shunt active filters, and hybrid active filters. New topologies using multilevel inverters are also discussed.