SHUNT ACTIVE FILTER USING INTELLIGENT CONTROLLERS BASED ON THREE-LEVEL (NPC) INVERTER TO COMPENSATE CURRENT HARMONICS

Abstract

Shunt active power filter or power-line conditioner is fundamental equipment used to compensate reactive power and suppress harmonics generated by non-linear loads. The conventional scheme is based on the two level inverter controlled by hysteresis controller. This configuration presents some drawbacks particularly high inverse voltage applied to power components, degraded quality of the output voltage inverter waveforms in addition this configuration is limited to low power applications. Today three-level (NPC) inverter represents a good alternative for several industrial applications, secondly artificial neural networks and fuzzy logic Controllers are increasingly used for power electronic converters control. To take advantages of three-level inverter topology and intelligent techniques performance a new scheme of shunt active filter system based on these controllers is proposed in this work. The control strategy adopted is the synchronous reference currents detection method which gives excellent performance. To compensate losses inverter and maintain the dc voltage across capacitors constant a proportional integral controller is used. The numerical simulation is developed and performed using MATLAB-Simulink and SimPowerSystem Toolbox. The obtained results in transient and steady states show the effectiveness of the proposed shunt active filter configuration based on these intelligent current controllers.