插电式混合动力汽车纯电动行进间启动发动机的平顺性控制

针对单电机插电式混合动力汽车在纯电动行进间电动机启动发动机时由于系统输出转矩变化进而引起整车冲击的问题,分析得到发动机点火时刻的不同及离合器接合状态的不同是造成转矩波动的原因。在此基础上,提出了基于离合器主、从动盘转速差和电机角加速度为输入量的离合器压力模糊控制的混合动力汽车模式切换动态协调控制策略,并对比了发动机目标转速点火和怠速转速点火的控制效果。最后通过台架试验以及实车道路试验对提出的控制策略进行了验证。结果表明,基于目标转速点火的协调控制策略能减小整车的冲击度。     

插电式混合动力汽车能量管理策略研究现状和发展趋势

目前国内外学者对插电式混合动力汽车能量管理策略进行了较为广泛和深入的研究,取得了良好的节能减排效果,为进一步提升其性能,有必要对插电式混合动力汽车能量管理策略的研究现状进行总结并对其发展趋势进行分析。首先对插电式混合动力汽车动力源能量流分配方法进行了归纳和分析,指出了当前插电式混合动力汽车能量管理策略两个亟待解决的问题：未考虑发动机冷却液温度和三元催化器温度等温度因素对油耗和排放影响;当前插电式混合动力汽车能量管理策略是以行驶功率需求作为输入,忽略了驾驶室制冷/供暖功率需求。最后提出了计及发动机冷却液温度和三元催化器温度等温度因素的能量管理策略和计及驾驶室制冷/供暖功率需求的能量管理策略两个未来研究方向。     

Coordinated torque control strategy for driving-mode-switch of strong hybrid electric vehicle

For a new type of strongly hybridized system, the vehicle ride performance is used as the study goal, a coordinated control strategy is put forward to suppress the torque surge after the analysis of the parameters changes of engine, motor, clutch and transmission during the driving-mode-switch process. The strongly hybridized vehicle simulation model is developed based on the coordinated control strategy. The typical drive mode switching process performance simulation and analysis are performed. The results show that introducing the coordinated control strategy reduces the torque surge during the driving-mode-switch process and improves the vehicle drivability.     

Model predictive control strategy of a medium hybrid electric vehicle

The intense coupled and nonlinear behaviors were observed on the tall long span tower line systems which were under the icing and wind loads in heavy icing areas. A set of stiffness equations of insulator, conductor and boundary conditions was deduced. Taking the ±800 kV UHV DC transmission line from Xiangjiaba to Shanghai as an example, the simplified numerical model of transmission tower, conductor, insulator and constraint was developed. The long span transmission tower line system models under seven loads conditions were analyzed by static nonlinear methods. It was found that the P Δ effect of tower components was small when the covered ice was uniformly distributed. The unbalanced wire loads on the tower would lead to twist effect when the covered ice was uneven distributed. The axial forces, moments at restraint nodes and the longest cantilever member were greatly affected by the P Δ effect, under which the unfavorable effect on the structure should be considered.     

Control strategy of regenerative braking for hybrid electric vehicle based on engine braking

Focusing on a continuously variable transmission(CVT) hybrid electric vehicle with integrate starter generator(ISG), modeling and simulating of engine braking was conducted. An optical control strategy of regenerative braking was put forward. When there is no regenerative braking, engine brake force can be used effectively by changing the CVT ratio to reduce the braking force requirements for wheel brakes based on the calculated results of engine braking. When there is regenerative braking, the braking priority sequence is generator braking, engine braking, and finally frictional braking. A forward simulation model for regenerative braking system of hybrid electric vehicle was built. The simulation and analysis under typical driving cycles was conducted. The result shows the control strategy and the models are reasonable and feasible.     

Hardware in the loop test for plug-in hybrid electric vehicle

Mathematical modes of engine,cooperation of motor and batteries,automatic clutch and vehicle are built with analysis of configuration of plug-in hybrid electric vehicle (PHEV). Specifications of data input and output and signal characters are defined. Hardware in the loop (HIL) system based on MATLAB/xPC for PHEV is built up. The motor/engine drive shift control logic test of PHEV is carried with inputting real acceleration pedal data. Testing results show that automatic clutch acts abnormally. Bugs in control logic are found out. Road test results with revised control logic are very good.     

Development of the remote data supervisory system of the hybrid electric vehicle

Taking the hybrid electric vehicle as the investigation subject, this paper studies the remote data acquisition, supervisory control and redisplay system of the hybrid electric vehicle fault diagnosis. The system gathers the simulate CAN BUS data through serial ports by the data acquisition device and send data to the remote web servers by the GPRS wireless communication module. For the demands and features, the paper makes the module selection and design the hardware of lower computer ,and the software on the host computer and lower computer. It takes several notebooks as the simulate vehicle date emission source to make an experiment, achieving the function of wireless data transfer, data acquisition, supervisory, redisplay for multi hybrid electric vehicles at the same time, and protocol setting up. Especially the function of wireless data transfer and protocol setting up, make a big progress on the common use and convenience of fault diagnosis system.     

Model predictive control for a plug-in hybrid electric vehicle

The dynamic programming is applied to model predictive control configuration, and a predictive control mathematics model is established for the fuel economy of plug-in hybrid electric vehicles (HEVs) based on spatial-domain. A global optimal method for plug-in HEVs is studied with dynamic programming, and the results indicate that the state of charge (SOC) is reduced slowly from the maximum at a trip’s initiation to the low threshold at the destination. The theoretical SOC slope is proposed to be taken as the reference slope of model predictive control, and the theoretical reference contrail of SOC is modified according to the especial driving modes in future. The results show that the predictive control effect of this method is approached to the calculation result of global optimal and fuel consumption is obviously reduced.     

Coordinated pressure control of a regenerative braking system based on a hybrid electric vehicle with an integrated startor and generator

With a focus on a Changan hybrid electric vehicle (HEV) with an integrated startor and generator (ISG), strategies for braking force distribution and coordinated pressure control are put forward, and a dynamic braking control model is constructed for off     

Study on global optimization control strategy of ISG velocity coupling hybrid electric vehicle

Hybrid system has the advantage of energy conservation and environmental protection. To improve the fuel economy of a hybrid system,based on the structure of the ISG velocity coupling HEV(hybrid electric vehicle),a dynamics simulation model is built. By using dynamic programming(DP) global optimization method,the variables of the engine throttle and the motor torque are set as the control variables,and the engine speed and the battery SOC are set as the state variables,the engine fuel economy is set as the objective function,and the battery SOC balance and the limited frequent shifting are set as the additional cost function. Then a global optimization program is built,and the simulation results indicate that the fuel economy of DP control HEV is 35.5% more efficient than that of the conventional vehicle.     

Ratio control strategy for solving system response lag of continuously variable transmission system

Generally, there’s a system response lag in the continuously variable transmission system, and this leads to a deviation of the engine work point from the optimal operation line of the minimum fuel consumption. To reduce the influence of system response lag, a new CVT ratio control strategy with the system response lag parameter during computing target ratio is proposed. Simulation results indicate that the proposed control strategy can overcome the effect of system response lag, so as to keep the engine work point on the optimal operation line effectively. A comparison of fuel consumption is made between the proposed control strategy and the traditional one by simulation, and results indicate that the proposed control strategy reduces the fuel consumption of the system by 2.85％.     

Research on Current Situation and Trend of Control Strategies for Hybrid Electric Vehicles

The vehicle's driving performances is determined by the control strategies and constructions of hybrid electric vehicles (HEV). The constructions of HEV are classified according to the change of state of charge of battery pack, and a study on current situation and trend of control strategies for HEV is presented in this paper. The research indicated that the current control strategies for HEV are not perfect and need further optimization. The control strategies should realize the optimum match among engine, motor, battery and transmission according to the characteristics of each component and vehicle's driving conditions. Many aspects including the fuel economy, emission, the life of battery pack, drivability, the reliability of each component and HEV's manufacture cost should be considered in the control strategies. A study on the control strategies and its optimization that take account of the aspects mentioned above is a work emphasis in the future. This paper also points out the PHEV equipped with small motor, small engine and continuously variable transmission is an ideal system construction for getting optimal fuel economy, lower emissions, steady drivability, lower manufacture cost and HEV's mass.