THE HIGH PERFORMANCES OF A SEVEN LEVELS ACTIVE POWER FILTER WITH A FUZZY LOGIC CONTROLLER UNDER A HIGH VOLTAGE

Abstract

This paper proposes a new perspective in the contribution to the purifying of harmful harmonics in the electric power distribution network. This perspective consists of using a seven-level parallel active filter that reveals superior qualities to those of the conventional two-level active filter. The three-phase seven-level inverter is equipped with a fuzzy controller, designed to keep the DC bus voltage constant. In order to effectively compensate the disturbances responsible of the performance degradation of the electrical equipment, the active filtering is treated according to an approach based on the use of the instantaneous active and reactive power method. Consequently the power factor unity, the sine wave current source and the minimal reactive power will be improved. The control strategy used to command the inverter switches is the intersective six-carrier PWM. These latter offers to the filtering operation a high stability and robustness in the various perturbations proposed in this work. The performed robustness tests clearly show the efficiency and the stability of the adopted approach for the SAPF, and this justifies the use of this type of filter in the field of high voltage and great power such as electrical traction.

Keywords

• Fuzzy controller
• Shunt active power filter (SAPF)
• Theory (p-q)