A Electric Bicycle Use Of Lithium Battery Charger Design

With the development of the society, people pay more and more attention to energy crisis and energyefficiency or other energy problems. Recently, lithium battery powered electric vehicle will take the placeof the oil fired vehicle. In our home market, the price of electric bicycle is low, and it wins warm praisefrom customers. The lithium battery of the electric bicycle’s age have involvement with the battery charger.This paper have designed a charger basic on the switching mode power supply for electric bicycle.Thischarger has Power Factor Correction circuit and battery charger balance, output voltage is42V, outputcurrent is4A.The paper give a brief introduction to the background of the subject, including charge characteristic,discharge characteristic and temperature characteristic. The charger design includes power source design,compensation circuit design, the control part design and shows part of the design. The power source designcontent as follows, an active DC/DC converter based on the boost power factor correction circuit, thepower switch control by the L4981chip, power factor correction effect is better; A half bridge type switchpower supply as the main of the system power supply circuit, the power supply switch controlled byUC3846chip, it use current model which include voltage and current2-ring to control the voltage currentstable the output. It make a detailed instructions to the magnetic core material choice, the magnetic coresof calculation method, the main source and Power Factor Correction circuit in the module control part ofthe design procedures of the feedback loop is another focuses on the place. It summarizes the equalizationcircuit the classification and all kinds of equalization circuit principle of work, also chose this chargerapplicable charge equalization circuit;. it design a charger compensation circuit to compensate for chargingprocess in the circuit impedance loss. Each module in the Simulink, through the simulation results of the analysis, the article concludes that this scheme can achieve the purpose of the design. The software only tothe software flow chart makes brief introduction.Now, compared with common electric bicycle used lithium battery charger, higher control precision,the battery protection more fully, and each part of the modular design, flexible combination according toactual situation needed, more convenient. The design of the middle power charger, but the design train ofthought can be used as big power charger circuits.