Research On Sliding Mode Control Of Active Power Filters

With the rapid development of power electronic technology, a large number of nonlinear devices are applied to industrial applications, as a result of the problem of harmonic pollution is becoming more and more serious.The traditional passive filter has been unable to meet the more an more high requirement of power quality,then active power filter (APF) arises at the historic moment.It has been recognized as the best means to restrain harmonic and compensating reactive power,so it has a great application prospect.This paper makes a brief introduction on the basic concept,the origin,the related domestic and foreign standard of harmonic,then introduce the research background and current situation,topology structure and the basic principle of active power filter and do the detail of kinds of control strategies and harmonic detect algorithm.Sliding Mode Control(SMC) was born in the 50s of 20th century,the theory has been perfect after more than 50 years’ development.But there is relatively few application in industrial field and fewer in APF.This paper makes a detailed explanation of the development history,the basic principle and control method of SMC,and makes a briefly introduce of the origin and suppression method of buffeting.In this paper SMC is applied in the single-phase and three-phase four-wire APF on the basis of previous studies.In single-phase APF,this paper puts forward two kinds of SMC strategies and introduce their principles,control processes in detail,then make comparative analysis of the two strategies,given their similarities and differences;In three-phase four-wire APF,we combine SMC with 3D space vector and make the control vector selection rules using the phase Angle of d-q coordinate and the equivalent control.Finally,we do the simulation research in the MATLAB/SIMULINK environment analyze its steady state and dynamic performance and compared with the traditional control strategy.The simulation results proved the effectiveness and superiority of the proposed strategy.