Region Adaptive Control Strategy For Boost Switching Power Converter

The stability of power converter is the focus of scholars. Especially in DC distributed power system and new energy power generation, the stability of power converter is becoming more prominent as the input and output of the system is in a wide rang of dynamic changes. So the power converter based on small signal linear model can not ensure its performance. This paper focus on one control method based on region adaptive to ensure its ability to adapt system working point vary and improve its performance.Firstly, a method to determinate the boundary of power converter is proposed. Based on traditional small signal linear model of Boost converter, the closed loop characteristic equation of system is deducted. We can obtain the stability boundary inequality equations using the routh criterion. Using the numerical method to solve these inequality equations, we can get the boundary of switching power converter in the end. Simulation and experiment results prove its correctness. The boundary of power converter can be the guides of converter design.Secondly, region adaptive controller is used to boost converter with average current control to consummate its application area. The working area is divided into multi areas based on the boundary of power converter so the multi working points can be determined. Controller of each working point is designed to constitute the region adaptive controller. Simulation and experiment result indicates that the region adaptive control can improve its working area of power converter.Finally, to reduce the switching disturbance of traditional region adaptive control, an improved region adaptive control structure is proposed. This paper analyses the different switching disturbance between traditional switching structure and the improved switching structure and obtain the decisive parameter influencing the scale of the disturbance. Simulation and experiment results indicate that the improved switching structure has little switching disturbance and little influence on the output. A new structure of region adaptive control is proposed based on the improved switching structure. Simulation and experiment results indicate its better dynamic response than traditional region adaptive control, and improved the working area of power converter.