Application Research On D-STATCOM Control Method Of Three Phase Four Wire System

With the continuous development of China’s power electronics technology,the three-phase four-wire system is more and more widely used in the distribution network,making the distribution network more and more demanding on the power quality,so the impact of power quality problems on the power grid is also more and more worthy of attention.Distribution grid static synchronous synchronous compensator(D-STATCOM)plays an important role in harmonic suppression in distribution network power quality improvement devices,and is currently a hot topic in research related to improving power quality.The main content of this study is to study and analyze the D-STATCOM control method of three-phase four-wire system,to improve the traditional modulation algorithm in view of the complexity of the algorithm and other problems,so as to reduce the complexity of the algorithm and improve the efficiency of the algorithm in the D-STATCOM application.Based on the structural characteristics of the three-phase four-wire D-STATCOM,the main circuit of the split formula in the three-phase four-wire capacitor is determined and its working principle is summarized,and the ip-iq detection method based on reactive power theory is selected as the harmonic detection method of the split D-STATCOM in the three-phase four-wire capacitor,and finally the 3D-space vector wide modulation(3D-SVPWM)control method is selected The principles and characteristics are analyzed and the traditional modulation algorithm is improved,the improved 3D-SVPWM modulation algorithm is improved,the improved 3D-SVPWM control method is used as its control strategy,the effectiveness and feasibility of the improved 3D-SVPWM modulation algorithm are verified by establishing the simulation model in MATLAB/Simulink,and the application of the model improved modulation algorithm and the application of traditional modulation algorithm are simulated and compared.The simulation results show that the calculation of the improved 3D-SVPWM modulation algorithm is simpler than that of the traditional3D-SVPWM modulation algorithm,and the calculation of the improved 3D-SVPWM modulation algorithm is much simpler,and the calculation of the algorithm is greatly reduced and the complexity of the algorithm is reduced,with better harmonic suppression function and good work efficiency.The simulation results verify the validity and feasibility of the study.