Analysis and evaluation of control techniques for active power filters: sliding mode control and proportional-integral control

This paper presents a three-phase shunt active power filter controlled by three different control strategies using a digital signal processor (DSP). The control techniques analyzed and compared are: sliding mode control (SMC), proportional-integral control (PI), and sliding mode control with proportional-integral controller (SMC-PI). Analysis and modeling of the shunt active power filter as well as simulation and experimental results are presented. The results show that the SMC controller has a better performance than PI and SMC-PI, allowing a low THD in the AC mains current and a fast transient response.