Shunt Active Power Filter Device And Its Related Technology Research

In recent years harm of the harmonic wave in the power grid isbecoming more and more serious,and has caused the deterioration ofpower quality and had a great pollution in power distributionsystem,which has become one of the problems that should not beignored in power supply system. As a kind of effective measures toimprove the quality of power grid,active power filter can compensateharmonic current and reactive power,which has a wide range ofapplication and research.This article has mainly studied for shunt activepower filter device and its related technologies.This paper first points out the harm of harmonic for the electricnetwork,introduces the current commonly used control measures,anddescribes the classification and development trend of active powerfilter.The paper is mainly focused on the control principle of shunt activepower filter, SAPF main circuit mathematical model are given, andanalyzed.In addition,the paper also enumerates the harmonic detectionmethods of shunt active power filter.Detecting the harmonic and reactivecurrent component accurately and quickly is one of the key technologiesof SAPF compensation.This paper emphatically points out thei p iqharmonic detection algorithm based on instantaneous reactive powertheory.Others, this paper analyzes and illustrates the current trackingcontrol methods of shunt active power filter.This paper puts forward anew method which can improve low frequency characteristic of PWM---continuous waveform modulation (CWM).The paper has a further studyof the reason of DC side capacitor voltage fluctuation when SAPF isworking, focuses on the control of dc side capacitor voltage, andanalyzes the traditional PI control method that is improved at the sametime.The paper chooses the improved fuzzy PI controller to maintain stability of the dc side capacitor voltage, which can rapidly andaccurately determine the parameters setting of PI controller.Finally, through simulation software PSCAD,the paper establishesthe whole circuit simulation model of shunt active power filter, andcarries on the simulation experiment and analysis.This paper also hascarried on the SAPF hardware circuit design, and respectivelyintroduces four parts of the SAPF control system circuit.The conclusiongives the practical effect using SAPF device, which shows that SAPFcan restrain harmonic and improve power quality, and verifies thefeasibility of using the shunt active power filter.