Compensadores estáticos de potência para sistemas trifásicos.

Abstract

This master work present a study about universal active power filter, studing differents aspects found in the literature. A review about the main power quality techniques until then desenvolving is made, it put in evidence the major functions and the cases where each one is more appropriate. The Universal active power filter is implemented by the junction of one shunt and one serie active power filter. This way, is make previously a model and analyses of each filter working individualy, and then is make the analyse of the universal active power filter scheme. The union of the serie and shunt active power filter became possible the compensate of source voltage and load current simultaneously, this way the universal scheme is the most complete technique to improve power quality. For serie active power filter is explored, beyond the load voltage compensate, the current source controler, but not in the same time. In a similar way, is explored for shunt active power filter the compensate of load voltage, beyond of the typical use of source current controler. When the current control is realized, the load voltage is "free", imposed by the circuit behavior. On the other hand, in the load voltage control, the source power factor isn't imposed. This way, by the study of steady state, its is verify the behavior of current and voltage of the system, to finding out the point or points that result in load voltage close to nominal valor when the current control is realized and the biggest source power factor when the load voltage control is done. In the universal active power filter, the sharing of the dc bus of both converters make has a degree of freedom of the fase load voltage, this way, the analyse of steady state is used for figure out which values of fase load voltage result in less currents and voltages, consequently less power loss.