新型蓄电池挖掘机设计及动力系统参数匹配

Design of a New Battery Excavator and the Matching of the Parameters of the Power System

针对电动挖掘机动性差,电池容量衰减快导致电池续航能力低的问题,设计一种新型蓄电池挖掘机,完成了供电车及电缆自动收放装置的结构设计,提升整机机动性.分析了已有动力系统匹配方法的不足,提出基于电池放电特性的电池组容量匹配方法并给出SOC估算策略.该方法分析了放电倍率和放电深度对电池组容量估算的影响,通过不同倍率的放电试验建立其目标电池的Peukert放电模型,根据Peukert对实际工况下电池实际容量衰减进行补偿修正,提高匹配精度;最后,在20kW工况条件下进行300h循环试验,验证系统功能的实用性和设计方法的正确性.

To solve the problem of poor mobility and low battery endurance,a new battery excavator was designed and the structure design of the automatic retractable device of the power supply vehicle and cable was completed,which can improve the mobility of the whole machine.The shortcomings of commonly used battery system matching methods were analyzed.A battery pack capacity matching method based on battery discharge characteristics has been proposed.And the SOC estimation strategy and implementation method are given.The method analyzes the effect of discharge ratio and discharge depth on the capacity estimation of battery pack.The Peukert discharge model of the target battery was established by different rate discharge tests.According to the Peukert model,the capacity compensation was modified to improve the matching precision.Finally,the 300h cycle test was carried out under the 20kW condition to verify the correctness of the design of the system parameters.