Research On Active Ripple Compensation Method Of Buck Power Converter

Buck circuit is Relatively elementary circuit topologies of non-isolated power converters.The strong point of Buck converters is simple circuit structure and smooth output current ripple.It is widely used in various electric energy conversion occasions.Output voltage ripple and efficiency of power conversion are important parameters to measure the quality of switching power supplies.Larger output voltage ripple will deteriorate the output power quality and even cause electromagnetic compatibility problems.It is very important to improve the performance of Buck converters by reducing output voltage ripple.With the further popularization and application of the Ga N & Si C in power converters,the efficiency of power supply also has been exalted.This topic is based on the background mentioned above,focusing on the output ripple compensation of Buck converters.The parallel Buck is used as the circuit topology,and the wide band gap device with low rated drain current is mixed and matched with traditional silicon-based devices.Suppress the output current pulsation of Buck power converters,reduce switching losses,reduce production costs,and promote the application of wide bandgap devices.firstly,this article analyzes and compares the current main solutions for reducing output voltage ripple,and focuses on the advantages and disadvantages of the various solutions currently proposed;Secondly,based on the absorption and summary of the current domestic and foreign proposals,a ripple compensation design method based on the mixing and matching of silicon-based devices and wide bandgap devices is proposed.This method includes the nexus betwixt the compensation branch inductance and the switching frequency of compensation branch.The nexus betwixt output current ripple and hysteresis circularity breadth is used as a theoretical support for guiding the design of compensation branch inductance and hysteresis loop width;Then the method proposed in the article is modeled and analyzed in detail,and compared with the transfer function of Buck converter,which is used to guide the theoretical basis of the compensation loop design.in the light of the theoretical analysis and formula derivation of the previous chapters,a simulation circuit model was founded adopting Simulink simulation software to carry out simulation test.Based on the current ripple compensation method proposed in the article proto was devised,the availability of the exoterica suggested in this article was demonstrated by proto;Finally,The error betwixt the tentative results and the theoretical calculation has been analyzed,and the scarcity in the practical application process of the scheme proposed in the article,a more in-depth thinking and prospect are carried out.