Control And Energy Management Strategies Of Multiple-input Bidirectional DC-DC Converter

With the increasingly serious energy crisis and environmental problems, the newenergy development and utilization has become an inevitable trend. By combining varietyof new forms of energy and energy storage device, a high energy efficiency can beachieved and a stable power output can be obtained. In the new energy power supplysystem, DC-DC converter is required in each new energy power generation unit and theenergy storage unit, which converts the eletrical energy to DC output, which connected tothe DC bus terminal. In order to integrate the system topology and control structure, amultiple-input DC-DC converter is used instead of the original multiple separate powerconverter, it can simplify the new energy supply system structure, reduce the system cost.In this paper, by using the photovoltaic cell and battery as the input source, a research isdone on the multiple- input DC-DC converter control and energy management strategy.In this paper, multiple-input bidirectional half-bridge converter system is selected asresearch topology, based on a large number of domestic and foreign information,According to the energy transfer directions, the working process of the circuit is dividedinto two positive and negative state, combined with the circuit work waveform of positiveand negative to analysis the circuit principle. and three working modes of the circuit isproposed according to the different energy relationshipThis paper is focused on the system closed loop control and energy managementstrategy. In order to achieve photovoltaic maximum power tracking control and ensure thestability of the output voltage, to determined the PWM + phase shift control strategy. Therunning status of the whole system is verified through Matlab simulation, the simulationresults show that the closed loop control strategy is effective, when the output power ofphotovoltaic cell or the load power is changed, the system can realize the working modeswitching automatically.Finally, the system hardware circuit and the main components of the parameters weredesigned in this paper. A system experimental platform is built, with the DSP chipdsPIC33FJ16GS504 as the control core, By software programming, working process of the system was verified by the experiment. The feasibility and correctness of the proposedtheory are verified according to the experimental results and the simulation waveforms,basically achieve the research objectives.