Research On Full-Bridge Three Port Converter

With the increasing depletion of traditional energy and worse environmental pollution,new energy becomes more promising and more attractive due to advantages such as: clean and inexhaustible and etc.However,new energy like solar,wind are unstable and easy to be influenced by the environment.It becomes great necessity to add one or more auxiliary power source to achieve power balancing between different ports.Multi-port converters are preferred in such power systems because of their simple topologies,high power density and high coefficient of utilization of device.So this thesis studies on a three-port converter applied in solar and storage battery system.The primary side of full bridge three port converter is two interleaving Boost structure,whose input inductor can effectively suppress the current ripple,thereby reducing the current ripple which will bring damage to the energy sources.This thesis adopt half bridge structure as the secondary side,in the meantime extend arrangement of zero voltage switching by adding an auxiliary circuit.The improved converter featuring in high density,high coefficient of device as well as lower switching losses is very suitable for solar and storage battery system.In this paper,the working principle and characteristics of the converter are analyzed in detail,the necessity and influence of the auxiliary circuit are specific analyzed.Additional,the control strategy of the converter is given to ensure the converter can run normally.According to the target,the key parameter of main part,controlling part is designed.A 500 W prototype of the converter is built and tested.Both simulation and experiment results proved that the analysis is correct.