Electric Vehicle Battery Charging System Design

The main content of this paper is to design and implement a charging system for low voltage and high current.This system is supplied to the electric vehicle charging.The system imitating the Tesla Motors battery packs and design a battery of independent board, 50 18650 lithium cobalt oxide group all in parallel. The system is designed push-pull power supply module provides low-voltage, high-current charging power supply, use BUCK circuit buck the voltage, using MCU based on feedback from the dynamic regulate the duty cycle of the PWM waveform.The system of the first stage’s Forward Switching Power Supply used to provide the power let the220 Vdown to 12 V, the second stage use BUCK circuit let the 12 V down to an appropriate voltage to the battery pack load, the third stage using current, voltage feedback of the load let the voltage, current real-time acquisition to MCU, through dynamic control MCU output the duty cycle of the PWM.The system uses lithium cobalt oxide 18650 by arrangement, drilling, fixed,packaging, creating a mold to form a battery module boxes are basically similar to Tesla showcased battery.The system realizes the task requirements, the large number of simulation test system is running well, to justify this system design is feasible.The innovation of this system is that the PWM waveform is directly provided by the micro without intermediate modulation PWM chip, thus cost savings. Utilizing the suspension drive module directly drive BUCK circuit MOS tube, so that the power supply modular obvious and easy to debug, the charging system is also more compact,space-saving costs.Software algorithms used Quicksort algorithm sample sequencing,faster the sampling data processing speed.