Comprehensive Control Of Reactive Harmonic In Low Voltage Distribution Network

Today,with the development of the society,the load in the low voltage distribution system is becoming more and more complex.The rise of small workshops,the use of a large number of power electronic devices,will make a large number of harmonic current,reactive power,zero sequence current and three-phase imbalance in the distribution network.These situations are becoming more and more serious,which brings great harm to the reliable operation of the power system and the power quality.People living in the life of today's increasingly high,the higher the quality of the electric power is becoming.In view of the above situation,the static var generator(SVG)based on the reactive power compensation technology,to meet the low voltage three-phase four wire distribution network economic operation under the condition of reactive power compensation strategy for low voltage distribution network is studied.In the analysis of the compensation results,this paper establishes a load simulation model based on MATLAB/Simulink,which contains harmonic,zero sequence current and three-phase unbalance.The simulation results show that the SVG designed in this paper has a good effect on the low voltage three-phase four wire distribution network.After the compensation of SVG,the number of harmonics in the system is reduced,the zero sequence current is almost zero,and the three-phase unbalance is also improved obviously.The specific work of this paper is as follows:(1)On the basis of reading a large number of documents,familiar with the basic working principle of SVG,using SVG to control low-voltage distribution network and the establishment of SVG in low-voltage three-phase four wire distribution system mathematical model.(2)Taking into account the load distribution of low voltage distribution network,the compensation strategy and the current detection link of SVG are studied in this paper,which makes SVG adapt to the environment of low voltage distribution network,to meet the conditions,to replace the previous compensation equipment.(3)Based on a large number of theoretical studies,this paper establishes a compensation system of SVG compensation low voltage four phase distribution network based on MATLAB/Simulink.Through the analysis of the simulation results,it is proved that the SVG compensation system has achieved the expected effect on the low voltage three-phase four wire system.