Study On Chaos Control Strategy Of Single-phase Inverter

In recent years,with the rapid development of domestic economy,the consumption of traditional energy is increasing,and the environmental pollution is becoming increasingly serious.Therefore,the research on photovoltaic and wind power systems formed by using renewable clean energy such as solar energy and wind energy has become particularly important.As an important part of the new energy system,the inverter may have complex nonlinear dynamic behaviors,such as boundary collision bifurcation and Hopf bifurcation,due to the existence of a large number of switching devices and nonlinear components,thus affecting the stable operation of the new energy system.Therefore,it is of practical and instructive significance to deeply study the chaotic behavior of H-bridge inverter and find a control method that can effectively restrain its chaotic behavior.In this dissertation,the chaotic behavior of different types of inverters is deeply studied,and different controls are applied to different types of inverters to effectively inhibit the chaotic behavior.The main research contents of this paper are as follows:Firstly,the working principle of single-phase H-bridge inverter is analyzed,and its discrete mapping iteration model is constructed by ststrobe mapping method.The chaotic behavior of the system with the variation of input voltage E and scale coefficient k_pis studied in detail by bifurcating diagram,folding diagram and eigenvalue trajectory diagram.On this basis,the traditional Time Delay Feedback Control(TDFC)is introduced to suppress the chaotic behavior.Secondly,according to the shortcomings of weak stability domain and weak disturbance immunity of traditional time-delay feedback control,Exponential Delayed Feedback Control(EDFC)and Improved Cosinoidal Delayed Feedback Control(ICDFC)are proposed to suppress the chaotic behavior of single-phase H-bridge inverter respectively,and the effectiveness of the control is demonstrated by numerical simulation comparison.The results show that the improved delay feedback control can increase the stability range of single-phase H bridge inverter and improve the disturbance immunity of the system.Finally,Time Delay Feedback Control(TDFC)is extended to LC type second order inverter.The bifurcation points and stability of the system after adding chaos control are analyzed by the bifurcation diagram and eigenvalue trajectory diagram,and the effectiveness of control is verified by numerical simulation.