纯电动商用车机械式自动变速器综合换挡策略

A Comprehensive Shift Strategy of Automatic Mechanical Transmission for Pure Electric Commercial Vehicles

为了使装有机械式自动变速器（AMT）的纯电动商用车的换挡时机能够更好地兼顾动力性和经济性，提出一种综合换挡策略。为提高工况适应性而引入负载识别思想，通过制动踏板信号、加速踏板开度及其变化率、车速、加速度等控制参数来识别汽车行驶工况，并采用工况分层处理。结合驾驶员意图和动力电池荷电状态（SOC）来制定综合换挡控制策略，采用正交设计法对控制策略参数进行优选，建立了整车的基于 MATLAB/Simulink 与 CRUISE 软件的联合仿真模型。研究结果表明：仿真分析和实车试验的数据规律吻合良好，表明了仿真模型的适用性。在实车加速性能试验中，采用综合换挡规律 0~50km/h和 50~70km/h 的加速时间分别为 23.48s 和 24.38s，与动力性换挡规律接近，明显优于经济性换挡规律；在实车郊区路况的经济性试验中，采用综合换挡规律的电池 SOC 值减小 3.51%，与经济性换挡规律接近，同样优于动力性换挡规律，证明本文提出的综合换挡控制策略达到预期研究目标。

A comprehensive shift strategy is proposed to consider both the power and economic performances in the shift timing for pure electric commercial vehicles equipped with automatic mechanical transmission（AMT）. The load detection is introduced to improve working adaptability,and the working conditions are identified from some control parameters such as the brake pedal signal,the opening of the accelerator pedal and its change rate,velocity,acceleration,and so on,and are processed hierarchically.The development of the comprehensive shift strategy combines the driver intention and power battery state of charge（SOC）,and the orthogonal method is used to find the optimal parameters of the control strategy.A joint simulation model based on MATLAB/Simulink and CRUISE is established.It is shown that the results from simulation analysis coincide with the test results well,and the proposed simulation model is applicable.The acceleration time for 0~50km/h and 50~70km/h is 23.48 sand 24.38 s in power performance tests when the vehicle is driven with the comprehensive shift schedule.Both of the results are close to those of the power shift schedule,and obviously superior to those of the economic shift schedule.The battery SOC value of the proposed strategy decreases by3.51%in an economic performance test,and it is close to the economic shift schedule result,and superior to the power shift schedule result.It can be concluded that the prospective goal is achieved by using the proposed comprehensive shift schedule.