The Research Of Modularization Of High Power High Frequency And Low Voltage Power Supply

The electrolytic power supply usually have high power and requires a greater current to the load.The quality of the power supply is very important to the the electrolytic product.As the main energy consumer of the electrolytic industry,the efficiency of the power supply is directly related to the energy saving of the whole industry.Therefore,the high-quality,high-performance power supply is an development trend of the industry.Traditional SCR electrolytic power supply is bulky,low efficiency,poor reliability,slow response,which is gradually replaced by high-frequency soft-switching power supply.High-frequency soft-switching modular power supply have the advantage of light weight,small size,standardization,high efficiency.Modular power supplies are typically powered by several or more power modules in series or in parallel.Due to the differences between the modules,there is a problem that the current is not equalized when the power supply modules are connected in parallel,and there is a problem of voltage imbalance in series.In order to solve these problems,this paper has studied the soft switching technology,parallel current sharing technology and series voltage equalization technology respectively.This research designer a high-power switching supply for electropkating is 36kW output power based on building block design;its output is 36V/1000A.At first,the basic structure of the electrolytic power supply is introduced,and the basic principle of ZVS phase-shifted full-bridge soft-switching and the condition of realizing soft-switching are introduced.On this basis,the main circuit of the electrolytic power supply is designed.Including the design of the main circuit topology and the calculation and selection of the various components.And then the PI parameters of the closed-loop control system are calculated.Which was verified by simulation analysis.For the parallel current sharing problem between power modules,the digital current sharing method and the maximum current sharing method are combined to design a maximum current automatic current sharing method based on CAN bus communication technology.For the problem of the series voltage equalization between the modules,we use the output voltage equalization control method.Both methods were verified by simulation.The hardware and software design of the electrolytic power supply control circuit system is carried out.The hardware and software components of the electrolytic power supply control circuit system are selected.The hardware is selected as the core controller with TMS320F28035 chip and the sampling circuit,the driving circuit,the protection circuit and the CAN communication circuit are designed.The software part designs the control system based on the related algorithm of DSP28035,gives the software flow chart.Finally,two power module prototypes were designed,and the experiment of single and two power supplies was experimentally verified.The experimental results show that the designed power module meets the design specifications The experimental results show that the design of the power module in line with the design indicators,a single power module dual closed-loop mode to achieve a stable current and voltage output,to achieve a soft switch.The two power modules are well-balanced and current-sharing.