Research On Multi-input Charging Device Based On Echelon Utilization Of Power Batteries

With the rapid development of the electric vehicle industry,the number of decommissioned car power batteries has also exploded.Relevant data shows that when the car power battery capacity is less than 80% of the rated capacity,the battery's performance can no longer meet the requirement of daily use in electric vehicles.That means that dismantling and retired power batteries will cause great waste of resources and environmental pollution.In addition to the decline in chemical activity of this type of power battery,the internal chemical composition of the battery has not changed.Among them,30% of the capacity can still be used in areas with low power fluctuations and low power supply stability,such as the energy storage area in electric vehicle charging stations.To realize the application of retired batteries in electric vehicle charging stations,the first step is that battery classification and reorganization.How to solve the acquisition of data such as battery capacity based on the existing battery capacity prediction model is the key in battery classification and reorganization.A multi-factor battery capacity prediction model was proposed in this paper,and the superiority of the model in prediction accuracy was verified by different types of battery capacity prediction.In this way,this article provides a more effective method for the classification and reorganization of retired batteries.Secondly,this article proposes the configuration concept and detailed description of the function of the new charging device.Through the functional description and the technical requirements of the device,the electrical components inside the device were selected,focusing on selection,and steps of production of the boost inductor,filter capacitor,transformer,IGBT and diode,then use the simulation results to compare with the actual calculated values to determine the correctness of the selected components.After the component selection of the multi-input charging device is completed,this paper simulates the DC/DC1,DC/DC2,and AC/DC based on the Simulink module in the MATLAB environment under extreme boost conditions,focusing on the analysis of their respective output currents and voltage changes under extreme conditions.This paper built the circuit simulation model diagram according to the different working modes of the multi-input charging device,and uses the simulation results in different working modes to analyze whether the output voltage and current of the device meet the technical requirements.Besides,the control logic of the multi-input charging device is elaborated.Finally,this paper used D & V EPT-150 test bench to test the multi-output charging device,and analyzed the efficiency change of the device under a certain input voltage,and focuses on the output voltage and current of the multi-input charging device based on the presence and absence of input filter inductance,in that way,this paper proved that the positive effect of the input filter inductor on protect the full-functional running of the device.In addition,in order to avoid the problem of size interference between the device case and the circuit component during the actual assembly process of the multi-input charging device,this paper uses CATIA to build a three-dimensional model of the device case to solve the size interference problem.In this paper,an effective and high-precision model for predicting battery capacity was proposed.Meanwhile,this paper completes the component selection,simulation and experiments of multi-input charging devices from the perspective of battery cascade utilization,which provides a method for the cascade utilization of retired batteries and it solved the problem of waste of retired battery resources in a practical way.