Study On Buck/boost Three Input DC Converter

With the progress of science and the continuous improvement of people’s livingstandard, people’s demand on the traditional energy is increasing. Thus above all caused asevere shortage of traditional energy and increasingly heavier environmental pollution.Development and utilization of new energy already is the most effective approach to solvethe environmental pollution and energy crisis. But most of the new energy are limited byclimate condition, what’s more, the energy density is low, and power supply is not stablediscontinuous. To overcome the shortcomings, scholars have proposed hybride renewablepower system, using the complementary of new energy to get continuous stability ofelectric power.In this system, using a multiple input converter instead of many single inputconverter, which can simplify struture and reduce the cost. This paper in view ofbuck/boost three input dc power supply system is launched research work, introducing theoperational principle of a three-input converter, the relationship between a variety of inputand output. This power supply system of simple structure, easy to expand, three differentinput source can simultaneously or separately supply power to the load, etc. In order torealize the renewable energy fisrt use, this paper designs a set of perfect control strategy torealize the management of all kinds of new energy which completes power of the load isprovided by renewable power source as much as possible and the rest is provided by theother. According to three input dc converter, this paper establishes the main and controlcircuit’s small signal model, and then puts forward the three input dc converterclosed-loop regulator design methods, and finally gives the parameters of the closed-loopregulator. This method can guarantee the converter stably working in each mode, andamong all kinds of work modes can smoothly transfer. Finally after PSIM softwaresimulation validation, this paper builds 400W principle prototype validates by experiment.Simulation and experimental results both show that the rationality of the design of circuitand the effectiveness of energy management strategy. Based on a bi-directional three-input dc converter as an example, this paperintroduces it and improves the new energy utilization. What’s more, this paper designs thecontrol strategy of bi-directional three-input dc converter to realize two-way flow ofenergy and ensure the new energy utilization. Finally after PSIM software simulationvalidation, this paper builds 400W principle prototype validates by experiment. Simulationand experimental results both show that the rationality of the design of circuit and theeffectiveness of energy management strategy.