Maf filter and hysteresis PWM based control algorithm for UPQC

The loads used in energy systems have gained diversity with the development of technology. The nonlinear loads is important for power quality. In recent years, nonlinear loads in energy systems have increased with the development of power electronic technologies. In parallel with these increases, power quality problems in energy systems have also increased. Electric energy systems and sensitive industrial loads are affected by power quality problems. Power quality problems are voltage sags and swells, voltage fluctuations, current and voltage harmonics, voltage unbalance and grid frequency variations. Eliminating power quality problems in the electric energy systems is great importance for both user and producers. Nowadays, devices that eliminate the power quality problems and produce solutions to problems have been developed. Passive and active power filters are widely used between these devices. The unified power quality conditioner (UPQC) has been developed as a solution to power quality problems and harmonics. The UPQC is formed by the serial connection of two voltage source inverters circuits using the common DC link. The first of these inverters is the series active power filter which operates as a voltage source and the second is the parallel active power filter which works as a current source. In this thesis, a new control method based on synchronous reference frame control is proposed for the UPQC system, which provides solution to power quality problems. In the proposed method, the hysteresis PWM or SVPWM techniques is used to obtain the switching signals. The PSIM package program has used in simulations.It is observed that the proposed control method with MAF filter based on synchronous reference frame is more successful in eliminating power quality problems compared to other control methods.