【作者】 高亮；

【导师】 张海波；

【作者基本信息】 东北电力大学 ， 机械工程， 2024， 硕士

【摘要】 电动叉车是一种使用电池作为能量来源的关键工业运输工具,它依靠电机来搬运和堆叠货物。与使用内燃机的叉车相比,电动叉车在环境保护方面有明显的好处,例如没有尾气排放、噪音水平低以及能源使用效率高,使其非常适合在室内环境中以及那些对环境保护有严格要求的场合使用。现在市场上的电动叉车大多采用固定传动比的传动系统,在不同的工作条件下,例如重载启动或上坡时,可能会因为单一的动力输出而表现出扭矩不足,无法适应不同的工作负载,并且在某些情况下,例如在平坦路面上高速行驶时,可能会因为电动机不在最佳效率范围内工作而导致能源消耗增加。本文对电动叉车的动力传动系统配置如何影响整车的性能进行了深入分析,并提出了一种采用两挡自动机械变速器(AMT)的方案,目的是提高电动叉车的动力性能,降低整车能耗。研究的主要内容总结如下:首先,基于目标电动叉车的整车参数和性能指标初步完成了该电动叉车的动力传动系统的合理选型与参数匹配设计。通过对传动系统进行深入分析,推导出了传动系统的合理传动参数区间,并分别设计了固定速比和两挡变速两种不同的传动方案,并初步确定了各个挡位的传动比数值。其次,根据电动叉车动力学理论分析构建了完整的电动叉车整车模型和动力性模型。整车模型包括车轮动力学模型、传动系统模型、电机及其控制器模型、电池组模型以及行驶工况模型等,而动力性模型则包含了车辆的最高车速、加速时间以及爬坡能力等多个关键性能指标,初步对比分析了固定速比和两挡变速这两种传动方案电动叉车的动力性能以及经济性能差异。此外,针对当前的自动变速器换挡规律进行研究分析,最终选择以加速踏板开度和车速作为换挡控制参数,制定了兼顾整车动力性和经济性的换挡规律。最后,通过粒子群优化算法分别对两种传动方案进行了优化研究。以加速时间和循环工况能耗作为目标函数,设定整车性能指标为约束条件,利用粒子群优化算法在设定范围内寻找最优解。结果显示:经过粒子群优化算法优化后的固定速比传动方案以及两挡变速传动方案在动力性和经济性方面均有一定提升,而且相较于固定速比传动方案,两挡变速传动方案展现出了显著优势,可提升整个电动叉车的动力性和经济性。更多还原

【Abstract】 Electric forklift is an industrial vehicle with battery as the power core,and the industrial vehicle realizes the functions of cargo handling and stacking through motor drive.Compared with forklifts driven by internal combustion engines,electric forklifts have outstanding advantages in environmental protection characteristics,including zero exhaust emissions,low noise pollution,and energy saving and high efficiency,which are especially suitable for indoor working environments and places with high requirements for environmental protection standards.At present,most of the electric forklifts on the market use a fixed speed ratio transmission device,in different working environments,such as heavy load starting or climbing,may appear to be insufficient torque because of a single power output,can not flexibly cope with different load requirements,and for some working conditions,such as high speed driving on flat roads,may increase energy consumption due to motor work is not in the optimal efficiency range.In this paper,the influence of the power transmission system configuration of electric forklifts on the performance of the whole vehicle is deeply studied,and a two-speed mechanical automatic transmission(AMT)scheme is proposed to improve the efficiency and power performance of electric forklifts.The main research contents are summarized as follows:Firstly,based on the vehicle parameters and performance indicators of the target electric forklift,the reasonable selection and parameter matching design of the power transmission system of the electric forklift were preliminarily completed.Through the in-depth analysis of the transmission system,we deduced the reasonable transmission parameter range of the transmission system,and designed two different transmission schemes of two-speed transmission and fixed gear,and preliminarily determined the transmission ratio value of each gear.Secondly,according to the theoretical analysis of electric forklift dynamics,a complete simulation model and dynamic evaluation model of electric forklift were constructed.The vehicle model includes the wheel dynamics model,the transmission system model,the motor and its controller model,the battery pack model and the driving condition model,etc.,while the dynamic model covers the top speed,acceleration time and climbing ability of the vehicle,and the dynamic performance and economic performance differences of the fixed gear reducer and the two-speed AMT transmission scheme electric forklift are preliminarily compared and analyzed.Furthermore,according to the current automatic transmission shift law,the acceleration pedal opening and vehicle speed were finally selected as the shift control parameters,and the shift law that took into account the power and economy of the whole vehicle was formulated.Finally,the particle swarm optimization algorithm is used to optimize the two transmission schemes.Taking the acceleration time and energy consumption under cyclic conditions as the objective function,and setting the performance index of the whole vehicle as the constraints,the particle swarm optimization algorithm is used to find the optimal solution within the set range.The results show that the single-speed reducer and two-speed transmission scheme optimized by the particle swarm optimization algorithm have certain improvements in power and economy,and compared with the single-stage reducer scheme,the two-speed AMT scheme shows significant advantages,which can improve the power and economy of the entire electric forklift.更多还原