The Design Of High Power Switching Mode Power Supply For Storage Battery

At present,as lead-acid batteries have the advantages of compact structure,good seismic performance,long life and being easy to maintain,they still play a main role in the area of batteries.Taking into account the characteristics of the battery,the main research content of this paper is to design and manufacture a high power switching power supply.Through the comparison and analysis of the common charging strategy of battery,the final plan is determined according to the charging and absorption curve of the battery.First gradually increase the output current level,in which keeping constant current charging.And then press the power supply maximum power output with constant voltage charging.At last when the battery close to saturation,keep a small current float charging until the battery is fully filled.The charging current waveform of the charging method is in good agreement with the optimum absorption curve of the battery.This article chooses the method of multi-module parallel to achieve high-power switching power supply output.By analyzing and comparing various current sharing control strategies,the final decision is using the method of adjusting the output impedance to solve this problem.Finish the hardware design of the switching power supply,including the access part,the output part and the power conversion part.The power module part mainly includes the design of the input and output filter links,the selection of the switch tube,the selection and design of the inductance parameters and the design of the control plate.For the peak current control mode,the slope compensation device is designed to realize the adaptive slope compensation.Under the premise of ensuring the slope compensation effect,let the compensation slope as small as possible.Modeling the current reversible chopper circuit with six-staggered parallel.Aiming at the peak current control mode,taking into account the link of the slope compensation link,calculate the exact math model of the topology.Using the small signal model of the topology,the open-loop transfer function of the converter is deduced.And then the frequency characteristics of the converter are analyzed by Matlab.Finish the design of the controller.Set up the experiment platform and debug the controller in the lower-power occasion.When the controller system can work stably,transfer the controller to the high power platform.The maximum output power of power module can reach up to 378 kW,the output current up to 600 A.When the switch tubes are working at the frequency of 5kHz,the temperature of switch tubes is increased by 50oC after 20 minutes.The indicators of switching power supply meet the design requirements.