Bi-directional Cuk DC/DC Converter Of Soft Switch Technology Research

Energy is the power of the development of human society, however, in the present circumstances, energy has become a major problem in harmonious and healthy development of human society because of the shortage of global traditional energy and environmental deteriorating increasingly. With the continuous mining of traditional energy consumption and pollution to the environment, it seriously restricted the sustainable development of human society. Solar energy is one kind of green pollution-free energy and its reservation is inexhaustible, which make it be the ideal alternative energy sources. In the technology of solar power generation, bidirectional DC/DC converter is an integral part of the independent photovoltaic power generation system, it is a hub of photovoltaic DC bus and energy storage system, scheduling and managing the two-way flow of energy between them. Thus, the bidirectional DC/DC converter is very important in the photovoltaic power generation system.Under the background of small power distributed photovoltaic system with energy storage segment, a deep research of the isolated bi-directional Cuk soft switch DC/DC converter is launched in this paper. Firstly, this paper briefly review the evolution of the bi-directional DC/DC converter and discuss the application scope, classification and the soft switch technology of bidirectional DC/DC converter. Secondly, this paper come up with improvation to bi-directional Cuk converter topology and make the key research on it, in order to realize the switch to soften and to enhance conversion efficiency as the goal, on the basis of detailed summarization and studying the soft switching technology of traditional Cuk converter topology and isolated bidirectional DC/DC converter. Paper analyzes the working principle of the improved topology and conversion current process in the improved topology in detail, and using Psim software has completed the open and closed loop simulation of different working mode to the improved topology to validate the correctness of theoretical analysis and the feasibility of the proposed improved topology. Finally, this paper introduces detailedly the designing of sampling circuit, isolating driver circuit and the components by calculation to the circuit parameters, and an experimental prototype was finished on the basis of the above.In the hardware system, the author has done experiments to improve the topology which achieve the expected effect to prove the rationality and validity of soft switch network based on digital processor TMS320F2812 in this paper.