Design Of Battery Management System For Electric Forklift And Test System Based On Battery Simulator

Today,when the energy problem is increasingly prominent,various industrial vehicles show a very obvious trend of defuelling,including forklifts that are widely used in industrial production operations.As a new type of industrial handling vehicle,electric forklift has the characteristics of easy operation,low noise,safety and environmental protection.Compared with traditional internal combustion forklift,it is more suitable for indoor and other small space operations.Taking advantage of relevant national policies,the application of electric forklifts will be much more widespread.Electric forklifts use the power battery pack loaded in the vehicle as the power source.The related technology of power battery becomes a key constraint factor in the performance development for electric forklifts.There must be a battery management system for electric forklifts which is responsible for monitoring and protecting the battery to extend battery life and improve the performance of the battery.In this paper,lithium battery power battery is used as the research object of electric forklift power source as well as the BMS,and the demand of electric forklift battery management system is analyzed.A battery management system that integrates single battery and battery pack parameter detection,charge detection,charge and discharge control,SOC estimation,battery balance control management,and CAN communi-cation,is designed specifically for electric forklifts.This article focuses on the design of the hardware and software of the BMS.Adopting a modular design scheme,encapsulating independent circuit logic functions,and in-depth study of the functional realization of the BMS,its whole hardware circuit is divided into four components: power supply module,main control module,slave control module and single voltage acquisition module.Using Freescale’s 16-bit automotive-grade microcontroller MC9S12DG256 and ST’s STM8L151 series microcontrollers as the master and slave modules respectively,and the battery voltage acquisition chip uses Linear’s third-generation multi-cell battery pack monitor LTC6804,Completed the design of the hardware part of the BMS.The software has been written to realize the corresponding functions of each hardware module,including accurate collection of battery parameters such as cell voltage,group voltage,temperature and current,intelligent control of battery balance,and correction of the SOC estimation algorithm based on actual operating conditions.The functions of fault cut-off and protection management make the operation more secure.In addition,the CAN communication protocol between the system and the upper computer has been developed to realize the real-time data upload and command reception of the system.This paper also studies the test system of the battery management system,focusing on the design of a single battery simulator that can be used to simulate real batteries,and builds a battery simulator platform to solve some of the functions of the test management system using real power battery packs.The resulting efficiency and safety issues.In the end,by building a test platform,the parameter collection performance and some functions of the battery management system are verified and tested.The experimental outcome demonstrate the usability of the battery management system developed in this paper.