The Research Of Double-Input Flyback Converter Based On DSP

With the development of economy, and the total quantity consumed of fossil fuels was increasing, the development and utilization of new energy is growing rapidly, solar energy, wind power, nuclear energy, hydrogen energy and many other new energy sources or renewable resources has aroused great interest. However, new energy sources have the shortcomings of low energy density, power supply instability, discontinuity, vulnerable to climate and other factors. If only one individual new energy supply was used as an independent power supply, its output is difficult to achieve the requirements of power stability. In this context, a variety of energy co-generation system came into being. The multi-input multi-energy converter as a core component of the combined multi-energy supply system, the research of the multi-input multi-energy converter is the basis to achieve the combined system of a variety of energy sources. Based on the existing multi-input fly-back converter, this paper selected dual-input single primary winding fly-back converter as the research object, expand analysis based on the object.Firstly, this paper analyzed the operating modes of the single primary winding fly-back converter as well as the relationship between the input and output voltages. Based on Saber, the main circuit open-loop model was established, the main waveform of the converter can be simulated from the model. For the presence of circuit current spike during the main power tube opened, detailed analysis of the causes of the spike was introduced, and some reasonable solutions were proposed. The simulation results show the effectiveness of the proposed solutions. Subsequently, this paper presents the design and selection of the detailed parameters of the major components and the converter, and the design of auxiliary circuits was given. The modules, ADC and PWM of the digital chip TMS320F28335 were presented.Then, some research of the closed loop control system was given, including a small signal modeling of the main circuit, a closed-loop controller design verification, and software programming work.Finally, based on performance requirements, a prototype of the rated output power of 120 W was produced, including the main circuit board prototype, auxiliary circuit board and SEED_DEC28335 digital control panel. And the experimental waveforms were given based on the steady-state and dynamic experiments, which verify the theoretical analysis.