Research On Filter Device Based On Flux Compensation Controllable Reactor

At present,power quality management of power system has become an important research field and power active filters are the main research direction of it in the future.In this thesis,we mainly study the flux compensation controllable reactor and apply it in the field of filtering.A series hybrid active power filter(SHAPF)based on the flux compensation controllable reactor has been designed and manufactured.Firstly,the development status of controllable reactors and active filters is expounded.The principle of flux compensation of reactors is analyzed from the perspective of magnetization curve of ferromagnetic materials in this dissertation.The correctness of the magnetic flux compensation principle is verified from the magnetic circuit using ANSYS and the PI current tracking control strategy and the overall system are simulated by Matlab.A small-capacity magnetic flux compensation controllable reactor prototype is designed and built in this exoeriment.The experimental platform is built to complete the magnetic flux compensation controllable reactor experiment.The results show that the inductance of reactor can realize stepless adj ustment of wide range.Then,the magnetic flux compensation controllable reactor is applied in the field of active filtering.By analyzing the topology of the existing series hybrid active filter,it is found that when the current is supplied to the control winding of the controllable reactor,the problem of phase-to-phase coupling appears,which will affect the effect of magnetic flux coImpensation.Aiming at this problem,a PI decoupling current tracking control strategy is proposed and a simplified mathematical model of the active filter based on the flux compensation controllable reactor is established.The system parameters are calculated and the inverter output filter inductance is optimized in Matlab.The fundamental current through the primary winding of the controllable reactor is extracted using the instantaneous reactive power theory.The command current is obtained by PI decoupling current tracking control strategy.The simulation results show that the filter system has good filtering effect,dynamic response,static stability,and can be extended to high voltage and large capacity system.Finally,a small-capacity filter system prototype is built according to the simulation parameters.The control circuit,main circuit,sampling circuit and passive filter branch are designed and manufactured.The final results are consistent with theoretical analysis and modeling simulation,which shows that the series hybrid active filter has obvious filtering effect and good application prospect.