针对双离合器自动变速器(Dual clutch transmission,DCT)变速弱混合动力轿车,考虑到起动发电一体化电机(Integrated starter and generator,ISG)转矩响应特性较快、转速/转矩控制精度高等特点,对其介入到换档过程时不同动力源输出转矩和离合器传递转矩协调鲁棒控制问题进行研究。建立体现DCT换档切换过程阶段差异性的动力学模型;考虑转矩相的离合器执行机构的响应能力和惯性相的模型不确定性和外界干扰(转速量测噪声和发动机转矩响应滞后),优化决策了动力源合成转矩;在需求转矩切换阶段,切换发动机转矩至驾驶员需求水平并退出ISG电机;基于系统效率最优对动力源合成转矩进行分配。基于Simulink的仿真试验表明所提出的换档控制策略能有效协调控制动力源转矩,并对模型不确定性和干扰有较强的抑制能力。为进一步验证策略进行的动态台架试验表明,所设计的转矩协调控制策略有效地解决了DCT换档过程中ISG电机、发动机以及双离合器之间的实时转矩协调控制问题,使其具有较好的换档品质。
Taking the hybrid electric vehicle equipped with dual clutch transmission(DCT) as the object and considering the characteristics of fast responding and high accuracy of integrated starter and generator(ISG) motor speed and torque, the robust control issue of torque coordination between twin clutches and power sources when ISG intervene with the gear-shifting process are investigated. The different dynamics models in the different phases of whole shifting process are established; Then, the power sources' synthesizing torque is optimally determined under the consideration of the responding characteristic of clutch actuators in the torque phase and the model uncertainty & external disturbance(measurement noise and engine torque’s lag) in the inertia phase; Afterwards, in the torque transition phase, the engine torque is switched into the level of driver demand and ISG torque is slowly come down. Finally, the torques of the power sources are distributed based on the optimization of system efficiency. The simulation results on the Simulink software platform illustrate that the proposed control strategies possess the capabilities of strong anti-uncertainty and anti-disturbance. And the following bench test results further show that it can also effectively address the coordinating control problems between the twin clutches and power sources, ensure that the vehicle has good quality in shift.