Research On Voltage Fluctuation Analysis And Suppression Method Of Distributed Generation

Global resource shortage,serious environmental pollution,climate warming and other issues are getting worse and worse,which has aroused great attention and concern all over the world.Therefore,the development and construction of new clean and green energy has become the primary task of the world energy agencies.Distributed Generation(DG)is a solution to the problem of energy shortage and environmental pollution in most countries of the world by making full use of renewable energy,with the advantages of small scale,less investment in research and development,convenient installation and power supply of equipment,good stability of power generation and green supply.However,with the large number of grid-connected distributed generation equipment,the voltage of distribution network fluctuates greatly.Therefore,in order to develop distributed generation on a large scale,it is of great practical significance to solve the voltage fluctuation of distribution network.In this thesis,the typical generation technology of distributed generation was summarized,and the generation principle of each technology and the voltage fluctuation caused by the technology itself were analyzed.By introducing the traditional concept of voltage fluctuation and its formation mechanism,the voltage fluctuation caused by DG connecting to distribution network was theoretically studied.The concept of permeability was introduced into the analysis of grid-connected voltage fluctuation of distributed power supply.The network model of IEEE33 nodes was built and studied deeply.The influence of DG on voltage fluctuation was analyzed when DG was connected to distribution network under different conditions.This paper has studied the impact of impulse current on voltage fluctuation when DG was connected to grid,and deeply analyzed the voltage variation of feeder under different conditions,and put forward relevant solutions.A new line Voltage Regulator(Line Voltage Regulator)which can suppress voltage fluctuation for DG grid-connected power supply lines was proposed.A kind of Magnetically Controlled Inductor(MCI)was studied.Based on the MCI,a circuit model was established.An experimental platform was built and the hardware of the device was tested.The simulation results showed that the device has the capability of stepless voltage regulation and high robustness.By calculating the Pearson coefficient of MCI correlation,the high linear correlation was verified.The simulation results showed that the device could suppress voltage fluctuation.